Start migration of apple skylark build API

RELNOTES: None.
PiperOrigin-RevId: 198107604

30 files changed, 1418 insertions, 785 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/BUILD b/src/main/java/com/google/devtools/build/lib/BUILD
index 7e4b7e0ca4..1c037a0f57 100644
--- a/src/main/java/com/google/devtools/build/lib/BUILD
+++ b/src/main/java/com/google/devtools/build/lib/BUILD
@@ -57,6 +57,7 @@ filegroup(
         "//src/main/java/com/google/devtools/build/lib/skyframe/packages:srcs",
         "//src/main/java/com/google/devtools/build/lib/skyframe/serialization:srcs",
         "//src/main/java/com/google/devtools/build/lib/skylarkbuildapi:srcs",
+        "//src/main/java/com/google/devtools/build/lib/skylarkbuildapi/apple:srcs",
         "//src/main/java/com/google/devtools/build/lib/skylarkbuildapi/cpp:srcs",
         "//src/main/java/com/google/devtools/build/lib/skylarkbuildapi/java:srcs",
         "//src/main/java/com/google/devtools/build/lib/skylarkbuildapi/platform:srcs",
diff --git a/src/main/java/com/google/devtools/build/lib/packages/Attribute.java b/src/main/java/com/google/devtools/build/lib/packages/Attribute.java
index 0bc32e4291..038f2a7837 100644
--- a/src/main/java/com/google/devtools/build/lib/packages/Attribute.java
+++ b/src/main/java/com/google/devtools/build/lib/packages/Attribute.java
@@ -38,6 +38,7 @@ import com.google.devtools.build.lib.events.Location;
 import com.google.devtools.build.lib.packages.RuleClass.Builder.RuleClassNamePredicate;
 import com.google.devtools.build.lib.skyframe.serialization.autocodec.AutoCodec;
 import com.google.devtools.build.lib.skyframe.serialization.autocodec.AutoCodec.VisibleForSerialization;
+import com.google.devtools.build.lib.skylarkbuildapi.SplitTransitionProviderApi;
 import com.google.devtools.build.lib.syntax.ClassObject;
 import com.google.devtools.build.lib.syntax.EvalException;
 import com.google.devtools.build.lib.syntax.EvalUtils;
@@ -276,7 +277,7 @@ public final class Attribute implements Comparable<Attribute> {
    * based on attributes of that rule. For instance, a split transition on a rule's deps may differ
    * depending on the 'platform' attribute of the rule.
    */
-  public interface SplitTransitionProvider {
+  public interface SplitTransitionProvider extends SplitTransitionProviderApi {
     /**
      * Returns the {@link SplitTransition} given the attribute mapper of the originating rule.
      */
diff --git a/src/main/java/com/google/devtools/build/lib/rules/apple/AppleCommandLineOptions.java b/src/main/java/com/google/devtools/build/lib/rules/apple/AppleCommandLineOptions.java
index da57b6ae74..42f6949455 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/apple/AppleCommandLineOptions.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/apple/AppleCommandLineOptions.java
@@ -29,10 +29,8 @@ import com.google.devtools.build.lib.skyframe.serialization.ObjectCodec;
 import com.google.devtools.build.lib.skyframe.serialization.SerializationContext;
 import com.google.devtools.build.lib.skyframe.serialization.SerializationException;
 import com.google.devtools.build.lib.skyframe.serialization.autocodec.AutoCodec;
-import com.google.devtools.build.lib.skylarkinterface.SkylarkModule;
-import com.google.devtools.build.lib.skylarkinterface.SkylarkModuleCategory;
+import com.google.devtools.build.lib.skylarkbuildapi.apple.AppleBitcodeModeApi;
 import com.google.devtools.build.lib.skylarkinterface.SkylarkPrinter;
-import com.google.devtools.build.lib.skylarkinterface.SkylarkValue;
 import com.google.devtools.common.options.Converters.CommaSeparatedOptionListConverter;
 import com.google.devtools.common.options.EnumConverter;
 import com.google.devtools.common.options.Option;
@@ -402,19 +400,8 @@ public class AppleCommandLineOptions extends FragmentOptions {
    * <p>This is a build-wide value, as bitcode mode needs to be consistent among a target and its
    * compiled dependencies.
    */
-  @SkylarkModule(
-    name = "apple_bitcode_mode",
-    category = SkylarkModuleCategory.NONE,
-    doc =
-        "The Bitcode mode to use when compiling Objective-C and Swift code on Apple platforms. "
-            + "Possible values are:<br><ul>"
-            + "<li><code>'none'</code></li>"
-            + "<li><code>'embedded'</code></li>"
-            + "<li><code>'embedded_markers'</code></li>"
-            + "</ul>"
-  )
   @Immutable
-  public enum AppleBitcodeMode implements SkylarkValue {
+  public enum AppleBitcodeMode implements AppleBitcodeModeApi {
 
     /** Do not compile bitcode. */
     NONE("none", ImmutableList.<String>of()),
diff --git a/src/main/java/com/google/devtools/build/lib/rules/apple/AppleConfiguration.java b/src/main/java/com/google/devtools/build/lib/rules/apple/AppleConfiguration.java
index 55b9b01a1e..22333bb41a 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/apple/AppleConfiguration.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/apple/AppleConfiguration.java
@@ -32,22 +32,16 @@ import com.google.devtools.build.lib.concurrent.ThreadSafety.Immutable;
 import com.google.devtools.build.lib.rules.apple.AppleCommandLineOptions.AppleBitcodeMode;
 import com.google.devtools.build.lib.rules.apple.ApplePlatform.PlatformType;
 import com.google.devtools.build.lib.skyframe.serialization.autocodec.AutoCodec;
-import com.google.devtools.build.lib.skylarkinterface.SkylarkCallable;
-import com.google.devtools.build.lib.skylarkinterface.SkylarkModule;
-import com.google.devtools.build.lib.skylarkinterface.SkylarkModuleCategory;
+import com.google.devtools.build.lib.skylarkbuildapi.apple.AppleConfigurationApi;
 import java.util.ArrayList;
 import java.util.List;
 import javax.annotation.Nullable;
 
 /** A configuration containing flags required for Apple platforms and tools. */
 @AutoCodec
-@SkylarkModule(
-  name = "apple",
-  doc = "A configuration fragment for Apple platforms.",
-  category = SkylarkModuleCategory.CONFIGURATION_FRAGMENT
-)
 @Immutable
-public class AppleConfiguration extends BuildConfiguration.Fragment {
+public class AppleConfiguration extends BuildConfiguration.Fragment
+    implements AppleConfigurationApi<PlatformType> {
   /**
    * Environment variable name for the xcode version. The value of this environment variable should
    * be set to the version (for example, "7.2") of xcode to use when invoking part of the apple
@@ -165,10 +159,7 @@ public class AppleConfiguration extends BuildConfiguration.Fragment {
    * platform or cpu for all actions spawned in this configuration; it is appropriate for
    * identifying the target cpu of iOS compile and link actions within this configuration.
    */
-  @SkylarkCallable(
-      name = "ios_cpu",
-      doc = "<b>Deprecated. Use <a href='#single_arch_cpu'>single_arch_cpu</a> instead.</b> "
-          + "The value of ios_cpu for this configuration.")
+  @Override
   public String getIosCpu() {
     return iosCpu;
   }
@@ -190,15 +181,7 @@ public class AppleConfiguration extends BuildConfiguration.Fragment {
    * <li>Use the default.
    * </ol>
    */
-  @SkylarkCallable(
-    name = "single_arch_cpu",
-    structField = true,
-    doc =
-        "The single \"effective\" architecture for this configuration (e.g., <code>i386</code> or "
-            + "<code>arm64</code>) in the context of rule logic that is only concerned with a "
-            + "single architecture (such as <code>objc_library</code>, which registers "
-            + "single-architecture compile actions)."
-  )
+  @Override
   public String getSingleArchitecture() {
     if (!Strings.isNullOrEmpty(appleSplitCpu)) {
       return appleSplitCpu;
@@ -272,13 +255,7 @@ public class AppleConfiguration extends BuildConfiguration.Fragment {
    * the context of rule logic which is only concerned with a single architecture (such as in {@code
    * objc_library}, which registers single-architecture compile actions).
    */
-  @SkylarkCallable(
-    name = "single_arch_platform",
-    doc = "The platform of the current configuration. This should only be invoked in a context "
-        + "where only a single architecture may be supported; consider "
-        + "<a href='#multi_arch_platform'>multi_arch_platform</a> for other cases.",
-    structField = true
-  )
+  @Override
   public ApplePlatform getSingleArchPlatform() {
     return ApplePlatform.forTarget(applePlatformType, getSingleArchitecture());
   }
@@ -296,12 +273,7 @@ public class AppleConfiguration extends BuildConfiguration.Fragment {
    * Otherwise, this will return a simulator platform.
    */
   // TODO(bazel-team): This should support returning multiple platforms.
-  @SkylarkCallable(
-    name = "multi_arch_platform",
-    doc = "The platform of the current configuration for the given platform type. This should only "
-        + "be invoked in a context where multiple architectures may be supported; consider "
-        + "<a href='#single_arch_platform'>single_arch_platform</a> for other cases."
-  )
+  @Override
   public ApplePlatform getMultiArchPlatform(PlatformType platformType) {
     List<String> architectures = getMultiArchitectures(platformType);
     switch (platformType) {
@@ -342,11 +314,7 @@ public class AppleConfiguration extends BuildConfiguration.Fragment {
    * #getMultiArchPlatform(PlatformType)}.
    */
   // TODO(b/28754442): Deprecate for more general skylark-exposed platform retrieval.
-  @SkylarkCallable(
-      name = "ios_cpu_platform",
-      doc = "<b>Deprecated. Use <a href='#single_arch_platform'>single_arch_platform</a> or "
-          + "<a href='#multi_arch_platform'>multi_arch_platform</a> instead.</b> "
-          + "The platform given by the ios_cpu flag.")
+  @Override
   public ApplePlatform getIosCpuPlatform() {
     return ApplePlatform.forTarget(PlatformType.IOS, iosCpu);
   }
@@ -393,13 +361,7 @@ public class AppleConfiguration extends BuildConfiguration.Fragment {
    *
    * @see AppleBitcodeMode
    */
-  @SkylarkCallable(
-    name = "bitcode_mode",
-    doc = "Returns the Bitcode mode to use for compilation steps.<p>"
-        + "This field is only valid for device builds; for simulator builds, it always returns "
-        + "<code>'none'</code>.",
-    structField = true
-  )
+  @Override
   public AppleBitcodeMode getBitcodeMode() {
     if (hasValidSingleArchPlatform() && getSingleArchPlatform().isDevice()) {
       return bitcodeMode;
diff --git a/src/main/java/com/google/devtools/build/lib/rules/apple/ApplePlatform.java b/src/main/java/com/google/devtools/build/lib/rules/apple/ApplePlatform.java
index cc8fb96b30..561843acb0 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/apple/ApplePlatform.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/apple/ApplePlatform.java
@@ -22,45 +22,16 @@ import com.google.devtools.build.lib.packages.Info;
 import com.google.devtools.build.lib.packages.NativeProvider;
 import com.google.devtools.build.lib.packages.Provider;
 import com.google.devtools.build.lib.packages.SkylarkInfo;
-import com.google.devtools.build.lib.skylarkinterface.SkylarkCallable;
-import com.google.devtools.build.lib.skylarkinterface.SkylarkModule;
-import com.google.devtools.build.lib.skylarkinterface.SkylarkModuleCategory;
+import com.google.devtools.build.lib.skylarkbuildapi.apple.ApplePlatformApi;
+import com.google.devtools.build.lib.skylarkbuildapi.apple.ApplePlatformTypeApi;
 import com.google.devtools.build.lib.skylarkinterface.SkylarkPrinter;
-import com.google.devtools.build.lib.skylarkinterface.SkylarkValue;
 import java.util.HashMap;
 import java.util.Locale;
 import javax.annotation.Nullable;
 
 /** An enum that can be used to distinguish between various apple platforms. */
-@SkylarkModule(
-  name = "apple_platform",
-  category = SkylarkModuleCategory.NONE,
-  doc = "Corresponds to Xcode's notion of a platform as would be found in "
-      + "<code>Xcode.app/Contents/Developer/Platforms</code>. Each platform represents an Apple "
-      + "platform type (such as iOS or tvOS) combined with one or more related CPU "
-      + "architectures. For example, the iOS simulator platform supports <code>x86_64</code> and "
-      + "<code>i386</code> architectures.<p>"
-      + "Specific instances of this type can be retrieved from the fields of the "
-      + "<a href='apple_common.html#platform'>apple_common.platform</a> struct:<br><ul>"
-      + "<li><code>apple_common.platform.ios_device</code></li>"
-      + "<li><code>apple_common.platform.ios_simulator</code></li>"
-      + "<li><code>apple_common.platform.macos</code></li>"
-      + "<li><code>apple_common.platform.tvos_device</code></li>"
-      + "<li><code>apple_common.platform.tvos_simulator</code></li>"
-      + "<li><code>apple_common.platform.watchos_device</code></li>"
-      + "<li><code>apple_common.platform.watchos_simulator</code></li>"
-      + "</ul><p>"
-      + "More commonly, however, the <a href='apple.html'>apple</a> configuration fragment has "
-      + "fields/methods that allow rules to determine the platform for which a target is being "
-      + "built.<p>"
-      + "Example:<br>"
-      + "<pre class='language-python'>\n"
-      + "p = apple_common.platform.ios_device\n"
-      + "print(p.name_in_plist)  # 'iPhoneOS'\n"
-      + "</pre>"
-)
 @Immutable
-public enum ApplePlatform implements SkylarkValue {
+public enum ApplePlatform implements ApplePlatformApi {
   IOS_DEVICE("ios_device", "iPhoneOS", PlatformType.IOS, true),
   IOS_SIMULATOR("ios_simulator", "iPhoneSimulator", PlatformType.IOS, false),
   MACOS("macos", "MacOSX", PlatformType.MACOS, true),
@@ -100,40 +71,17 @@ public enum ApplePlatform implements SkylarkValue {
     this.isDevice = isDevice;
   }
 
-  /** Returns the platform type of this platform. */
-  @SkylarkCallable(
-    name = "platform_type",
-    doc = "Returns the platform type of this platform.",
-    structField = true
-  )
+  @Override
   public PlatformType getType() {
     return platformType;
   }
 
-  /**
-   * Returns true if this platform is a device platform, or false if this is a simulator platform.
-   */
-  @SkylarkCallable(
-    name = "is_device",
-    doc = "Returns <code>True</code> if this platform is a device platform or <code>False</code> "
-        + "if it is a simulator platform.",
-    structField = true
-  )
+  @Override
   public boolean isDevice() {
     return isDevice;
   }
 
-  /**
-   * Returns the name of the "platform" as it appears in the CFBundleSupportedPlatforms plist
-   * setting.
-   */
-  @SkylarkCallable(name = "name_in_plist", structField = true,
-    doc = "The name of the platform as it appears in the <code>CFBundleSupportedPlatforms</code> "
-        + "entry of an Info.plist file and in Xcode's platforms directory, without the extension "
-        + "(for example, <code>iPhoneOS</code> or <code>iPhoneSimulator</code>).<br>"
-        + "This name, when converted to lowercase (e.g., <code>iphoneos</code>, "
-        + "<code>iphonesimulator</code>), can be passed to Xcode's command-line tools like "
-        + "<code>ibtool</code> and <code>actool</code> when they expect a platform name.")
+  @Override
   public String getNameInPlist() {
     return nameInPlist;
   }
@@ -246,26 +194,8 @@ public enum ApplePlatform implements SkylarkValue {
    * platform type (for example, watchOS) together with a cpu value (for example, armv7).
    */
   // TODO(cparsons): Use these values in static retrieval methods in this class.
-  @SkylarkModule(
-    name = "apple_platform_type",
-    category = SkylarkModuleCategory.NONE,
-    doc = "Describes an Apple \"platform type\", such as iOS, macOS, tvOS, or watchOS. This is "
-        + "distinct from a \"platform\", which is the platform type combined with one or more CPU "
-        + "architectures.<p>"
-        + "Specific instances of this type can be retrieved by accessing the fields of the "
-        + "<a href='apple_common.html#platform_type'>apple_common.platform_type</a>:<br><ul>"
-        + "<li><code>apple_common.platform_type.ios</code></li>"
-        + "<li><code>apple_common.platform_type.macos</code></li>"
-        + "<li><code>apple_common.platform_type.tvos</code></li>"
-        + "<li><code>apple_common.platform_type.watchos</code></li>"
-        + "</ul><p>"
-        + "Likewise, the platform type of an existing platform value can be retrieved using its "
-        + "<code>platform_type</code> field.<p>"
-        + "Platform types can be converted to a lowercase string (e.g., <code>ios</code> or "
-        + "<code>macos</code>) using the <a href='globals.html#str'>str</a> function."
-  )
   @Immutable
-  public enum PlatformType implements SkylarkValue {
+  public enum PlatformType implements ApplePlatformTypeApi {
     IOS("ios"),
     WATCHOS("watchos"),
     TVOS("tvos"),
diff --git a/src/main/java/com/google/devtools/build/lib/rules/apple/AppleToolchain.java b/src/main/java/com/google/devtools/build/lib/rules/apple/AppleToolchain.java
index cf6cbf5be6..21e3ffba45 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/apple/AppleToolchain.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/apple/AppleToolchain.java
@@ -27,18 +27,13 @@ import com.google.devtools.build.lib.concurrent.ThreadSafety.Immutable;
 import com.google.devtools.build.lib.packages.Attribute.LabelLateBoundDefault;
 import com.google.devtools.build.lib.packages.RuleClass;
 import com.google.devtools.build.lib.packages.RuleClass.Builder.RuleClassType;
-import com.google.devtools.build.lib.skylarkinterface.SkylarkCallable;
-import com.google.devtools.build.lib.skylarkinterface.SkylarkModule;
+import com.google.devtools.build.lib.skylarkbuildapi.apple.AppleToolchainApi;
 
 /**
  * Utility class for resolving items for the Apple toolchain (such as common tool flags, and paths).
  */
-@SkylarkModule(
-  name = "apple_toolchain",
-  doc = "Utilities for resolving items from the Apple toolchain."
-)
 @Immutable
-public class AppleToolchain {
+public class AppleToolchain implements AppleToolchainApi<AppleConfiguration> {
 
   // These next two strings are shared secrets with the xcrunwrapper.sh to allow
   // expansion of DeveloperDir and SDKRoot and runtime, since they aren't known
@@ -82,10 +77,6 @@ public class AppleToolchain {
   /**
    * Returns the platform directory inside of Xcode for a given configuration.
    */
-  @SkylarkCallable(
-    name = "sdk_dir",
-    doc = "Returns the platform directory inside of Xcode for a given configuration."
-  )
   public static String sdkDir() {
     return SDKROOT_DIR;
   }
@@ -93,31 +84,23 @@ public class AppleToolchain {
   /**
    * Returns the Developer directory inside of Xcode for a given configuration.
    */
-  @SkylarkCallable(
-    name = "developer_dir",
-    doc = "Returns the Developer directory inside of Xcode for a given configuration."
-  )
   public static String developerDir() {
     return DEVELOPER_DIR;
   }
 
   /**
-   * Returns the platform frameworks directory inside of Xcode for a given {@link ApplePlatform}.
+   * Returns the platform frameworks directory inside of Xcode for a given configuration.
    */
-  public static String platformDeveloperFrameworkDir(ApplePlatform platform) {
-    String platformDir = platformDir(platform.getNameInPlist());
-    return platformDir + "/Developer/Library/Frameworks";
+  public static String platformDeveloperFrameworkDir(AppleConfiguration configuration) {
+    return platformDeveloperFrameworkDir(configuration.getSingleArchPlatform());
   }
 
   /**
-   * Returns the platform frameworks directory inside of Xcode for a given configuration.
+   * Returns the platform frameworks directory inside of Xcode for a given {@link ApplePlatform}.
    */
-  @SkylarkCallable(
-    name = "platform_developer_framework_dir",
-    doc = "Returns the platform frameworks directory inside of Xcode for a given configuration."
-  )
-  public static String platformFrameworkDirFromConfig(AppleConfiguration configuration) {
-    return platformDeveloperFrameworkDir(configuration.getSingleArchPlatform());
+  public static String platformDeveloperFrameworkDir(ApplePlatform platform) {
+    String platformDir = platformDir(platform.getNameInPlist());
+    return platformDir + "/Developer/Library/Frameworks";
   }
 
   /** Returns the SDK frameworks directory inside of Xcode for a given configuration. */
@@ -157,6 +140,30 @@ public class AppleToolchain {
   }
 
   /**
+   * Returns the platform directory inside of Xcode for a given configuration.
+   */
+  @Override
+  public String sdkDirConstant() {
+    return sdkDir();
+  }
+
+  /**
+   * Returns the Developer directory inside of Xcode for a given configuration.
+   */
+  @Override
+  public String developerDirConstant() {
+    return developerDir();
+  }
+
+  /**
+   * Returns the platform frameworks directory inside of Xcode for a given configuration.
+   */
+  @Override
+  public String platformFrameworkDirFromConfig(AppleConfiguration configuration) {
+    return platformDeveloperFrameworkDir(configuration);
+  }
+
+  /**
    * Base rule definition to be ancestor for rules which may require an xcode toolchain.
    */
   public static class RequiresXcodeConfigRule implements RuleDefinition {
diff --git a/src/main/java/com/google/devtools/build/lib/rules/apple/BUILD b/src/main/java/com/google/devtools/build/lib/rules/apple/BUILD
index 4ad39bc4f1..d03e842b13 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/apple/BUILD
+++ b/src/main/java/com/google/devtools/build/lib/rules/apple/BUILD
@@ -23,6 +23,7 @@ java_library(
         "//src/main/java/com/google/devtools/build/lib/concurrent",
         "//src/main/java/com/google/devtools/build/lib/skyframe/serialization",
         "//src/main/java/com/google/devtools/build/lib/skyframe/serialization/autocodec",
+        "//src/main/java/com/google/devtools/build/lib/skylarkbuildapi/apple",
         "//src/main/java/com/google/devtools/common/options",
         "//third_party:guava",
         "//third_party:jsr305",
diff --git a/src/main/java/com/google/devtools/build/lib/rules/apple/DottedVersion.java b/src/main/java/com/google/devtools/build/lib/rules/apple/DottedVersion.java
index 189462e947..9919ff757d 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/apple/DottedVersion.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/apple/DottedVersion.java
@@ -22,11 +22,8 @@ import com.google.common.collect.ImmutableList;
 import com.google.common.collect.Ordering;
 import com.google.devtools.build.lib.concurrent.ThreadSafety.Immutable;
 import com.google.devtools.build.lib.skyframe.serialization.autocodec.AutoCodec;
-import com.google.devtools.build.lib.skylarkinterface.SkylarkCallable;
-import com.google.devtools.build.lib.skylarkinterface.SkylarkModule;
-import com.google.devtools.build.lib.skylarkinterface.SkylarkModuleCategory;
+import com.google.devtools.build.lib.skylarkbuildapi.apple.DottedVersionApi;
 import com.google.devtools.build.lib.skylarkinterface.SkylarkPrinter;
-import com.google.devtools.build.lib.skylarkinterface.SkylarkValue;
 import java.util.ArrayList;
 import java.util.Objects;
 import java.util.regex.Matcher;
@@ -72,16 +69,9 @@ import javax.annotation.Nullable;
  *
  * <p>This class is immutable and can safely be shared among threads.
  */
-@SkylarkModule(
-  name = "DottedVersion",
-  category = SkylarkModuleCategory.NONE,
-  doc =
-      "A value representing a version with multiple components, separated by periods, such as "
-          + "1.2.3.4."
-)
 @Immutable
 @AutoCodec
-public final class DottedVersion implements Comparable<DottedVersion>, SkylarkValue {
+public final class DottedVersion implements DottedVersionApi<DottedVersion> {
   private static final Splitter DOT_SPLITTER = Splitter.on('.');
   private static final Pattern COMPONENT_PATTERN = Pattern.compile("(\\d+)(?:([a-z]+)(\\d*))?");
   private static final String ILLEGAL_VERSION =
@@ -173,12 +163,7 @@ public final class DottedVersion implements Comparable<DottedVersion>, SkylarkVa
     return 0;
   }
 
-  @SkylarkCallable(
-      name = "compare_to",
-      doc =
-          "Compares based on most significant (first) not-matching version component. "
-              + "So, for example, 1.2.3 < 1.2.4"
-  )
+  @Override
   public int compareTo_skylark(DottedVersion other) {
     return compareTo(other);
   }
diff --git a/src/main/java/com/google/devtools/build/lib/rules/apple/XcodeConfigProvider.java b/src/main/java/com/google/devtools/build/lib/rules/apple/XcodeConfigProvider.java
index 50db482da5..589d6599e4 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/apple/XcodeConfigProvider.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/apple/XcodeConfigProvider.java
@@ -19,18 +19,15 @@ import com.google.devtools.build.lib.analysis.configuredtargets.RuleConfiguredTa
 import com.google.devtools.build.lib.concurrent.ThreadSafety.Immutable;
 import com.google.devtools.build.lib.packages.NativeInfo;
 import com.google.devtools.build.lib.packages.NativeProvider;
-import com.google.devtools.build.lib.skylarkinterface.SkylarkCallable;
-import com.google.devtools.build.lib.skylarkinterface.SkylarkModule;
+import com.google.devtools.build.lib.skylarkbuildapi.apple.XcodeConfigProviderApi;
 import javax.annotation.Nullable;
 
 /**
  * The set of Apple versions computed from command line options and the {@code xcode_config} rule.
  */
 @Immutable
-@SkylarkModule(
-    name = XcodeConfigProvider.SKYLARK_NAME,
-    doc = "The set of Apple versions computed from command line options and the xcode_config rule.")
-public class XcodeConfigProvider extends NativeInfo {
+public class XcodeConfigProvider extends NativeInfo
+    implements XcodeConfigProviderApi<ApplePlatform, ApplePlatform.PlatformType> {
   /** Skylark name for this provider. */
   public static final String SKYLARK_NAME = "XcodeVersionConfig";
 
@@ -66,18 +63,12 @@ public class XcodeConfigProvider extends NativeInfo {
     this.xcodeVersion = xcodeVersion;
   }
 
-  @SkylarkCallable(name = "xcode_version",
-      doc = "Returns the Xcode version that is being used to build.<p>"
-          + "This will return <code>None</code> if no Xcode versions are available.",
-      allowReturnNones = true)
+  @Override
   public DottedVersion getXcodeVersion() {
     return xcodeVersion;
   }
 
-  @SkylarkCallable(
-      name = "minimum_os_for_platform_type",
-      doc = "The minimum compatible OS version for target simulator and devices for a particular "
-          + "platform type.")
+  @Override
   public DottedVersion getMinimumOsForPlatformType(ApplePlatform.PlatformType platformType) {
     // TODO(b/37240784): Look into using only a single minimum OS flag tied to the current
     // apple_platform_type.
@@ -95,10 +86,7 @@ public class XcodeConfigProvider extends NativeInfo {
     }
   }
 
-  @SkylarkCallable(
-      name = "sdk_version_for_platform",
-      doc = "The version of the platform SDK that will be used to build targets for the given "
-          + "platform.")
+  @Override
   public DottedVersion getSdkVersionForPlatform(ApplePlatform platform) {
     switch (platform) {
       case IOS_DEVICE:
diff --git a/src/main/java/com/google/devtools/build/lib/rules/apple/cpp/AppleCcToolchain.java b/src/main/java/com/google/devtools/build/lib/rules/apple/cpp/AppleCcToolchain.java
index 1f14012e5f..dbe364e662 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/apple/cpp/AppleCcToolchain.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/apple/cpp/AppleCcToolchain.java
@@ -96,7 +96,7 @@ public class AppleCcToolchain extends CcToolchain {
             SDK_FRAMEWORK_DIR_KEY, AppleToolchain.sdkFrameworkDir(platform, ruleContext))
         .addStringVariable(
             PLATFORM_DEVELOPER_FRAMEWORK_DIR,
-            AppleToolchain.platformFrameworkDirFromConfig(appleConfiguration))
+            AppleToolchain.platformDeveloperFrameworkDir(appleConfiguration))
         .addStringVariable(
             XCODE_VERISON_OVERRIDE_VALUE_KEY,
             appleEnv.getOrDefault(AppleConfiguration.XCODE_VERSION_ENV_NAME, ""))
diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/AppleDynamicFrameworkInfo.java b/src/main/java/com/google/devtools/build/lib/rules/objc/AppleDynamicFrameworkInfo.java
index 6555f8a951..66011d412d 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/objc/AppleDynamicFrameworkInfo.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/AppleDynamicFrameworkInfo.java
@@ -19,9 +19,7 @@ import com.google.devtools.build.lib.collect.nestedset.NestedSet;
 import com.google.devtools.build.lib.concurrent.ThreadSafety.Immutable;
 import com.google.devtools.build.lib.packages.NativeInfo;
 import com.google.devtools.build.lib.packages.NativeProvider;
-import com.google.devtools.build.lib.skylarkinterface.SkylarkCallable;
-import com.google.devtools.build.lib.skylarkinterface.SkylarkModule;
-import com.google.devtools.build.lib.skylarkinterface.SkylarkModuleCategory;
+import com.google.devtools.build.lib.skylarkbuildapi.apple.AppleDynamicFrameworkInfoApi;
 import com.google.devtools.build.lib.vfs.PathFragment;
 import javax.annotation.Nullable;
 
@@ -40,12 +38,8 @@ import javax.annotation.Nullable;
  * </ul>
  */
 @Immutable
-@SkylarkModule(
-    name = "AppleDynamicFramework",
-    category = SkylarkModuleCategory.PROVIDER,
-    doc = "A provider containing information about an Apple dynamic framework."
-)
-public final class AppleDynamicFrameworkInfo extends NativeInfo {
+public final class AppleDynamicFrameworkInfo extends NativeInfo
+    implements AppleDynamicFrameworkInfoApi<PathFragment, Artifact> {
 
   /** Skylark name for the AppleDynamicFrameworkInfo. */
   public static final String SKYLARK_NAME = "AppleDynamicFramework";
@@ -80,55 +74,22 @@ public final class AppleDynamicFrameworkInfo extends NativeInfo {
     this.dynamicFrameworkFiles = dynamicFrameworkFiles;
   }
 
-  /**
-   * Returns the framework path names used as link inputs in order to link against the dynamic
-   * framework.
-   */
-  @SkylarkCallable(name = "framework_dirs",
-      structField = true,
-      doc = "The framework path names used as link inputs in order to link against the dynamic "
-          + "framework."
-  )
+  @Override
   public NestedSet<PathFragment> getDynamicFrameworkDirs() {
     return dynamicFrameworkDirs;
   }
 
-  /**
-   * Returns the full set of artifacts that should be included as inputs to link against the
-   * dynamic framework.
-   */
-  @SkylarkCallable(name = "framework_files",
-      structField = true,
-      doc = "The full set of files that should be included as inputs to link against the "
-          + "dynamic framework."
-  )
+  @Override
   public NestedSet<Artifact> getDynamicFrameworkFiles() {
     return dynamicFrameworkFiles;
   }
 
-  /**
-   * Returns the multi-architecture dylib binary of the dynamic framework. May return null if
-   * the rule providing the framework only specified framework imports.
-   */
-  @Nullable
-  @SkylarkCallable(name = "binary",
-      structField = true,
-      doc = "The multi-architecture dylib binary of the dynamic framework. May be null if "
-          + "the rule providing the framework only specified framework imports."
-  )
+  @Override
   public Artifact getAppleDylibBinary() {
     return dylibBinary;
   }
 
-  /**
-   * Returns the {@link ObjcProvider} which contains information about the transitive dependencies
-   * linked into the dylib.
-   */
-  @SkylarkCallable(name = "objc",
-      structField = true,
-      doc = "A provider which contains information about the transitive dependencies linked into "
-          + "the dynamic framework."
-  )
+  @Override
   public ObjcProvider getDepsObjcProvider() {
     return depsObjcProvider;
   }
diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/AppleSkylarkCommon.java b/src/main/java/com/google/devtools/build/lib/rules/objc/AppleSkylarkCommon.java
index efec1c23ad..9e4daaddb1 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/objc/AppleSkylarkCommon.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/AppleSkylarkCommon.java
@@ -39,9 +39,8 @@ import com.google.devtools.build.lib.rules.apple.XcodeConfigProvider;
 import com.google.devtools.build.lib.rules.apple.XcodeVersionProperties;
 import com.google.devtools.build.lib.rules.objc.AppleBinary.AppleBinaryOutput;
 import com.google.devtools.build.lib.rules.objc.ObjcProvider.Key;
-import com.google.devtools.build.lib.skylarkinterface.Param;
-import com.google.devtools.build.lib.skylarkinterface.SkylarkCallable;
-import com.google.devtools.build.lib.skylarkinterface.SkylarkModule;
+import com.google.devtools.build.lib.skylarkbuildapi.SkylarkRuleContextApi;
+import com.google.devtools.build.lib.skylarkbuildapi.apple.AppleCommonApi;
 import com.google.devtools.build.lib.syntax.Environment;
 import com.google.devtools.build.lib.syntax.EvalException;
 import com.google.devtools.build.lib.syntax.Runtime;
@@ -55,11 +54,8 @@ import javax.annotation.Nullable;
 /**
  * A class that exposes apple rule implementation internals to skylark.
  */
-@SkylarkModule(
-  name = "apple_common",
-  doc = "Functions for skylark to access internals of the apple rule implementations."
-)
-public class AppleSkylarkCommon {
+public class AppleSkylarkCommon
+    implements AppleCommonApi<Artifact, ObjcProvider, XcodeConfigProvider, ApplePlatform> {
 
   @VisibleForTesting
   public static final String BAD_KEY_ERROR = "Argument %s not a recognized key, 'providers',"
@@ -93,33 +89,12 @@ public class AppleSkylarkCommon {
     this.objcProtoAspect = objcProtoAspect;
   }
 
-  @SkylarkCallable(
-      name = "apple_toolchain",
-      doc = "Utilities for resolving items from the apple toolchain."
-  )
+  @Override
   public AppleToolchain getAppleToolchain() {
     return new AppleToolchain();
   }
 
-  @SkylarkCallable(
-    name = "platform_type",
-    doc =
-        "An enum-like struct that contains the following fields corresponding to Apple platform "
-            + "types:<br><ul>"
-            + "<li><code>ios</code></li>"
-            + "<li><code>macos</code></li>"
-            + "<li><code>tvos</code></li>"
-            + "<li><code>watchos</code></li>"
-            + "</ul><p>"
-            + "These values can be passed to methods that expect a platform type, like the 'apple' "
-            + "configuration fragment's "
-            + "<a href='apple.html#multi_arch_platform'>multi_arch_platform</a> method.<p>"
-            + "Example:<p>"
-            + "<pre class='language-python'>\n"
-            + "ctx.fragments.apple.multi_arch_platform(apple_common.platform_type.ios)\n"
-            + "</pre>",
-    structField = true
-  )
+  @Override
   public Info getPlatformTypeStruct() {
     if (platformType == null) {
       platformType = PlatformType.getSkylarkStruct();
@@ -127,23 +102,7 @@ public class AppleSkylarkCommon {
     return platformType;
   }
 
-  @SkylarkCallable(
-    name = "platform",
-    doc =
-        "An enum-like struct that contains the following fields corresponding to Apple "
-            + "platforms:<br><ul>"
-            + "<li><code>ios_device</code></li>"
-            + "<li><code>ios_simulator</code></li>"
-            + "<li><code>macos</code></li>"
-            + "<li><code>tvos_device</code></li>"
-            + "<li><code>tvos_simulator</code></li>"
-            + "<li><code>watchos_device</code></li>"
-            + "<li><code>watchos_device</code></li>"
-            + "</ul><p>"
-            + "These values can be passed to methods that expect a platform, like "
-            + "<a href='apple.html#sdk_version_for_platform'>apple.sdk_version_for_platform</a>.",
-    structField = true
-  )
+  @Override
   public Info getPlatformStruct() {
     if (platform == null) {
       platform = ApplePlatform.getSkylarkStruct();
@@ -151,218 +110,71 @@ public class AppleSkylarkCommon {
     return platform;
   }
 
-  @SkylarkCallable(
-    name = XcodeVersionProperties.SKYLARK_NAME,
-    doc =
-        "The constructor/key for the <code>XcodeVersionProperties</code> provider.<p>"
-            + "If a target propagates the <code>XcodeVersionProperties</code> provider,"
-            + " use this as the key with which to retrieve it. Example:<br>"
-            + "<pre class='language-python'>\n"
-            + "dep = ctx.attr.deps[0]\n"
-            + "p = dep[apple_common.XcodeVersionProperties]\n"
-            + "</pre>",
-    structField = true
-  )
+  @Override
   public Provider getXcodeVersionPropertiesConstructor() {
     return XcodeVersionProperties.SKYLARK_CONSTRUCTOR;
   }
 
-  @SkylarkCallable(
-      name = XcodeConfigProvider.SKYLARK_NAME,
-      doc = "The constructor/key for the <code>XcodeVersionConfig</code> provider.",
-      structField =  true
-  )
+  @Override
   public Provider getXcodeVersionConfigConstructor() {
     return XcodeConfigProvider.PROVIDER;
   }
 
-  @SkylarkCallable(
-    // TODO(b/63899207): This currently does not match ObjcProvider.SKYLARK_NAME as it requires
-    // a migration of existing skylark rules.
-    name = "Objc",
-    doc =
-        "The constructor/key for the <code>Objc</code> provider.<p>"
-            + "If a target propagates the <code>Objc</code> provider, use this as the "
-            + "key with which to retrieve it. Example:<br>"
-            + "<pre class='language-python'>\n"
-            + "dep = ctx.attr.deps[0]\n"
-            + "p = dep[apple_common.Objc]\n"
-            + "</pre>",
-    structField = true
-  )
+  @Override
   public Provider getObjcProviderConstructor() {
     return ObjcProvider.SKYLARK_CONSTRUCTOR;
   }
 
-  @SkylarkCallable(
-    name = AppleDynamicFrameworkInfo.SKYLARK_NAME,
-    doc =
-        "The constructor/key for the <code>AppleDynamicFramework</code> provider.<p>"
-            + "If a target propagates the <code>AppleDynamicFramework</code> provider, use this "
-            + "as the key with which to retrieve it. Example:<br>"
-            + "<pre class='language-python'>\n"
-            + "dep = ctx.attr.deps[0]\n"
-            + "p = dep[apple_common.AppleDynamicFramework]\n"
-            + "</pre>",
-    structField = true
-  )
+  @Override
   public Provider getAppleDynamicFrameworkConstructor() {
     return AppleDynamicFrameworkInfo.SKYLARK_CONSTRUCTOR;
   }
 
-  @SkylarkCallable(
-    name = AppleDylibBinaryInfo.SKYLARK_NAME,
-    doc =
-        "The constructor/key for the <code>AppleDylibBinary</code> provider.<p>"
-            + "If a target propagates the <code>AppleDylibBinary</code> provider, use this as the "
-            + "key with which to retrieve it. Example:<br>"
-            + "<pre class='language-python'>\n"
-            + "dep = ctx.attr.deps[0]\n"
-            + "p = dep[apple_common.AppleDylibBinary]\n"
-            + "</pre>",
-    structField = true
-  )
+  @Override
   public Provider getAppleDylibBinaryConstructor() {
     return AppleDylibBinaryInfo.SKYLARK_CONSTRUCTOR;
   }
 
-  @SkylarkCallable(
-    name = AppleExecutableBinaryInfo.SKYLARK_NAME,
-    doc =
-        "The constructor/key for the <code>AppleExecutableBinary</code> provider.<p>"
-            + "If a target propagates the <code>AppleExecutableBinary</code> provider,"
-            + " use this as the key with which to retrieve it. Example:<br>"
-            + "<pre class='language-python'>\n"
-            + "dep = ctx.attr.deps[0]\n"
-            + "p = dep[apple_common.AppleExecutableBinary]\n"
-            + "</pre>",
-    structField = true
-  )
+  @Override
   public Provider getAppleExecutableBinaryConstructor() {
     return AppleExecutableBinaryInfo.SKYLARK_CONSTRUCTOR;
   }
 
-  @SkylarkCallable(
-    name = AppleStaticLibraryInfo.SKYLARK_NAME,
-    doc =
-        "The constructor/key for the <code>AppleStaticLibrary</code> provider.<p>"
-            + "If a target propagates the <code>AppleStaticLibrary</code> provider, use "
-            + "this as the key with which to retrieve it. Example:<br>"
-            + "<pre class='language-python'>\n"
-            + "dep = ctx.attr.deps[0]\n"
-            + "p = dep[apple_common.AppleStaticLibrary]\n"
-            + "</pre>",
-    structField = true
-  )
+  @Override
   public AppleStaticLibraryInfo.Provider getAppleStaticLibraryProvider() {
     return AppleStaticLibraryInfo.SKYLARK_CONSTRUCTOR;
   }
 
-  @SkylarkCallable(
-    name = AppleDebugOutputsInfo.SKYLARK_NAME,
-    doc =
-        "The constructor/key for the <code>AppleDebugOutputs</code> provider.<p>"
-            + "If a target propagates the <code>AppleDebugOutputs</code> provider, use this as the "
-            + "key with which to retrieve it. Example:<br>"
-            + "<pre class='language-python'>\n"
-            + "dep = ctx.attr.deps[0]\n"
-            + "p = dep[apple_common.AppleDebugOutputs]\n"
-            + "</pre>",
-    structField = true
-  )
+  @Override
   public Provider getAppleDebugOutputsConstructor() {
     return AppleDebugOutputsInfo.SKYLARK_CONSTRUCTOR;
   }
 
-  @SkylarkCallable(
-    name = AppleLoadableBundleBinaryInfo.SKYLARK_NAME,
-    doc =
-        "The constructor/key for the <code>AppleLoadableBundleBinary</code> provider.<p>"
-            + "If a target propagates the <code>AppleLoadableBundleBinary</code> provider, "
-            + "use this as the key with which to retrieve it. Example:<br>"
-            + "<pre class='language-python'>\n"
-            + "dep = ctx.attr.deps[0]\n"
-            + "p = dep[apple_common.AppleLoadableBundleBinary]\n"
-            + "</pre>",
-    structField = true
-  )
+  @Override
   public Provider getAppleLoadableBundleBinaryConstructor() {
     return AppleLoadableBundleBinaryInfo.SKYLARK_CONSTRUCTOR;
   }
 
-  @SkylarkCallable(
-      name = "apple_host_system_env",
-      doc =
-          "Returns a <a href='dict.html'>dict</a> of environment variables that should be set "
-              + "for actions that need to run build tools on an Apple host system, such as the "
-              + " version of Xcode that should be used. The keys are variable names and the values "
-              + " are their corresponding values."
-  )
+  @Override
   public ImmutableMap<String, String> getAppleHostSystemEnv(XcodeConfigProvider xcodeConfig) {
     return AppleConfiguration.getXcodeVersionEnv(xcodeConfig.getXcodeVersion());
   }
 
-  @SkylarkCallable(
-      name = "target_apple_env",
-      doc =
-          "Returns a <code>dict</code> of environment variables that should be set for actions "
-              + "that build targets of the given Apple platform type. For example, this dictionary "
-              + "contains variables that denote the platform name and SDK version with which to "
-              + "build. The keys are variable names and the values are their corresponding values."
-  )
+  @Override
   public ImmutableMap<String, String> getTargetAppleEnvironment(
-      XcodeConfigProvider xcodeConfig, ApplePlatform platform) {
+      XcodeConfigProvider xcodeConfigApi, ApplePlatform platformApi) {
+    XcodeConfigProvider xcodeConfig = (XcodeConfigProvider) xcodeConfigApi;
+    ApplePlatform platform = (ApplePlatform) platformApi;
     return AppleConfiguration.appleTargetPlatformEnv(
         platform, xcodeConfig.getSdkVersionForPlatform(platform));
   }
 
-  @SkylarkCallable(
-      name = "multi_arch_split",
-      doc = "A configuration transition for rule attributes to build dependencies in one or"
-          + " more Apple platforms. "
-          + "<p>Use of this transition requires that the 'platform_type' and 'minimum_os_version'"
-          + " string attributes are defined and mandatory on the rule.</p>"
-          + "<p>The value of the platform_type attribute will dictate the target architectures "
-          + " for which dependencies along this configuration transition will be built.</p>"
-          + "<p>Options are:</p>"
-          + "<ul>"
-          + "<li><code>ios</code>: architectures gathered from <code>--ios_multi_cpus</code>.</li>"
-          + "<li><code>macos</code>: architectures gathered from <code>--macos_cpus</code>.</li>"
-          + "<li><code>tvos</code>: architectures gathered from <code>--tvos_cpus</code>.</li>"
-          + "<li><code>watchos</code>: architectures gathered from <code>--watchos_cpus</code>."
-          + "</li></ul>"
-          + "<p>minimum_os_version should be a dotted version string such as '7.3', and is used to"
-          + " set the minimum operating system on the configuration similarly based on platform"
-          + " type. For example, specifying platform_type 'ios' and minimum_os_version '8.0' will"
-          + " ensure that dependencies are built with minimum iOS version '8.0'.",
-      structField = true
-  )
+  @Override
   public SplitTransitionProvider getMultiArchSplitProvider() {
     return new MultiArchSplitTransitionProvider();
   }
 
-  @SkylarkCallable(
-    name = "new_objc_provider",
-    doc = "Creates a new ObjcProvider instance.",
-    parameters = {
-      @Param(
-        name = "uses_swift",
-        type = Boolean.class,
-        defaultValue = "False",
-        named = true,
-        positional = false,
-        doc = "Whether this provider should enable Swift support."
-      )
-    },
-    extraKeywords =
-        @Param(
-          name = "kwargs",
-          type = SkylarkDict.class,
-          defaultValue = "{}",
-          doc = "Dictionary of arguments."
-        ),
-    useEnvironment = true
-  )
+  @Override
   // This method is registered statically for skylark, and never called directly.
   public ObjcProvider newObjcProvider(
       Boolean usesSwift,
@@ -392,52 +204,7 @@ public class AppleSkylarkCommon {
     return resultBuilder.build();
   }
 
-  @SkylarkCallable(
-    name = "new_dynamic_framework_provider",
-    doc = "Creates a new AppleDynamicFramework provider instance.",
-    parameters = {
-      @Param(
-        name = AppleDynamicFrameworkInfo.DYLIB_BINARY_FIELD_NAME,
-        type = Artifact.class,
-        named = true,
-        positional = false,
-        doc = "The dylib binary artifact of the dynamic framework."
-      ),
-      @Param(
-        name = AppleDynamicFrameworkInfo.OBJC_PROVIDER_FIELD_NAME,
-        type = ObjcProvider.class,
-        named = true,
-        positional = false,
-        doc =
-            "An ObjcProvider which contains information about the transitive "
-                + "dependencies linked into the binary."
-      ),
-      @Param(
-        name = AppleDynamicFrameworkInfo.FRAMEWORK_DIRS_FIELD_NAME,
-        type = SkylarkNestedSet.class,
-        generic1 = String.class,
-        named = true,
-        noneable = true,
-        positional = false,
-        defaultValue = "None",
-        doc =
-            "The framework path names used as link inputs in order to link against the dynamic "
-                + "framework."
-      ),
-      @Param(
-        name = AppleDynamicFrameworkInfo.FRAMEWORK_FILES_FIELD_NAME,
-        type = SkylarkNestedSet.class,
-        generic1 = Artifact.class,
-        named = true,
-        noneable = true,
-        positional = false,
-        defaultValue = "None",
-        doc =
-            "The full set of artifacts that should be included as inputs to link against the "
-                + "dynamic framework"
-      )
-    }
-  )
+  @Override
   public AppleDynamicFrameworkInfo newDynamicFrameworkProvider(
       Artifact dylibBinary,
       ObjcProvider depsObjcProvider,
@@ -462,18 +229,10 @@ public class AppleSkylarkCommon {
         dylibBinary, depsObjcProvider, frameworkDirs, frameworkFiles);
   }
 
-  @SkylarkCallable(
-      name = "link_multi_arch_binary",
-      doc = "Links a (potentially multi-architecture) binary targeting Apple platforms. This "
-          + "method comprises a bulk of the logic of the <code>apple_binary</code> rule, and is "
-          + "exposed as an API to iterate on migration of <code>apple_binary</code> to skylark.\n"
-          + "<p>This API is <b>highly experimental</b> and subject to change at any time. Do not "
-          + "depend on the stability of this function at this time.",
-      mandatoryPositionals = 1 // The SkylarkRuleContext.
-  )
-  // TODO(b/70937317): Iterate on, improve, and solidify this API.
-  public NativeInfo linkMultiArchBinary(SkylarkRuleContext skylarkRuleContext)
+  @Override
+  public NativeInfo linkMultiArchBinary(SkylarkRuleContextApi skylarkRuleContextApi)
       throws EvalException, InterruptedException {
+    SkylarkRuleContext skylarkRuleContext = (SkylarkRuleContext) skylarkRuleContextApi;
     try {
       RuleContext ruleContext = skylarkRuleContext.getRuleContext();
       AppleBinaryOutput appleBinaryOutput = AppleBinary.linkMultiArchBinary(ruleContext);
@@ -483,28 +242,12 @@ public class AppleSkylarkCommon {
     }
   }
 
-  @SkylarkCallable(
-    name = "dotted_version",
-    doc = "Creates a new <a href=\"DottedVersion.html\">DottedVersion</a> instance.",
-    parameters = {
-      @Param(
-        name = "version",
-        type = String.class,
-        doc = "The string representation of the DottedVersion."
-      )
-    }
-  )
+  @Override
   public DottedVersion dottedVersion(String version) {
     return DottedVersion.fromString(version);
   }
 
-  @SkylarkCallable(
-    name = "objc_proto_aspect",
-    doc =
-        "objc_proto_aspect gathers the proto dependencies of the attached rule target,"
-            + "and propagates the proto values of its dependencies through the ObjcProto provider.",
-    structField = true
-  )
+  @Override
   public SkylarkAspect getObjcProtoAspect() {
     return objcProtoAspect;
   }
diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/AppleStaticLibraryInfo.java b/src/main/java/com/google/devtools/build/lib/rules/objc/AppleStaticLibraryInfo.java
index 6515719243..bfa557e29b 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/objc/AppleStaticLibraryInfo.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/AppleStaticLibraryInfo.java
@@ -17,11 +17,7 @@ package com.google.devtools.build.lib.rules.objc;
 import com.google.devtools.build.lib.actions.Artifact;
 import com.google.devtools.build.lib.packages.BuiltinProvider;
 import com.google.devtools.build.lib.packages.NativeInfo;
-import com.google.devtools.build.lib.skylarkinterface.Param;
-import com.google.devtools.build.lib.skylarkinterface.SkylarkCallable;
-import com.google.devtools.build.lib.skylarkinterface.SkylarkConstructor;
-import com.google.devtools.build.lib.skylarkinterface.SkylarkModule;
-import com.google.devtools.build.lib.skylarkinterface.SkylarkModuleCategory;
+import com.google.devtools.build.lib.skylarkbuildapi.apple.AppleStaticLibraryInfoApi;
 import com.google.devtools.build.lib.syntax.EvalException;
 
 /**
@@ -37,16 +33,7 @@ import com.google.devtools.build.lib.syntax.EvalException;
  *       included in this archive multiple times).
  * </ul>
  */
-@SkylarkModule(
-    name = "AppleStaticLibrary",
-    category = SkylarkModuleCategory.PROVIDER,
-    doc = "A provider containing information regarding multi-architecture Apple static libraries, "
-        + "as is propagated by the apple_static_library rule."
-)
-public final class AppleStaticLibraryInfo extends NativeInfo {
-
-  /** Skylark name for the AppleStaticLibraryInfo. */
-  public static final String SKYLARK_NAME = "AppleStaticLibrary";
+public final class AppleStaticLibraryInfo extends NativeInfo implements AppleStaticLibraryInfoApi {
 
   /** Skylark constructor and identifier for AppleStaticLibraryInfo. */
   public static final Provider SKYLARK_CONSTRUCTOR = new Provider();
@@ -65,26 +52,12 @@ public final class AppleStaticLibraryInfo extends NativeInfo {
     this.depsObjcProvider = depsObjcProvider;
   }
 
-  /**
-   * Returns the multi-architecture archive that {@code apple_static_library} created.
-   */
-  @SkylarkCallable(name = "archive",
-      structField = true,
-      doc = "The multi-arch archive (.a) output by apple_static_library."
-  )
+  @Override
   public Artifact getMultiArchArchive() {
     return multiArchArchive;
   }
 
-  /**
-   * Returns the {@link ObjcProvider} which contains information about the transitive dependencies
-   * linked into the archive.
-   */
-  @SkylarkCallable(name = "objc",
-      structField = true,
-      doc = "A provider which contains information about the transitive dependencies linked into "
-          + "the archive."
-  )
+  @Override
   public ObjcProvider getDepsObjcProvider() {
     return depsObjcProvider;
   }
@@ -92,33 +65,13 @@ public final class AppleStaticLibraryInfo extends NativeInfo {
    /**
     * Provider class for {@link AppleStaticLibraryInfo} objects.
     */
-  public static class Provider extends BuiltinProvider<AppleStaticLibraryInfo> {
+  public static class Provider extends BuiltinProvider<AppleStaticLibraryInfo>
+       implements AppleStaticLibraryInfoApi.AppleStaticLibraryInfoProvider<Artifact, ObjcProvider> {
     private Provider() {
       super(SKYLARK_NAME, AppleStaticLibraryInfo.class);
     }
 
-    @SkylarkCallable(
-        name = SKYLARK_NAME,
-        doc = "The <code>AppleStaticLibrary</code> constructor.",
-        parameters = {
-          @Param(
-              name = "archive",
-              type = Artifact.class,
-              named = true,
-              positional = false,
-              doc = "Multi-architecture archive (.a) representing a static library"),
-          @Param(
-              name = "objc",
-              type = ObjcProvider.class,
-              named = true,
-              positional = false,
-              doc = "A provider which contains information about the transitive dependencies "
-                  + "linked into the archive."),
-        },
-        selfCall = true)
-    @SkylarkConstructor(
-        objectType = AppleStaticLibraryInfo.class,
-        receiverNameForDoc = "apple_common.AppleStaticLibrary")
+    @Override
     public AppleStaticLibraryInfo appleStaticLibrary(
         Artifact archive, ObjcProvider objcProvider) throws EvalException {
       return new AppleStaticLibraryInfo(archive, objcProvider);
diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/BUILD b/src/main/java/com/google/devtools/build/lib/rules/objc/BUILD
index 371c58903a..5a2c8ca33d 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/objc/BUILD
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/BUILD
@@ -33,6 +33,8 @@ java_library(
         "//src/main/java/com/google/devtools/build/lib/rules/cpp",
         "//src/main/java/com/google/devtools/build/lib/shell",
         "//src/main/java/com/google/devtools/build/lib/skyframe/serialization/autocodec",
+        "//src/main/java/com/google/devtools/build/lib/skylarkbuildapi",
+        "//src/main/java/com/google/devtools/build/lib/skylarkbuildapi/apple",
         "//src/main/java/com/google/devtools/build/lib/vfs",
         "//src/main/java/com/google/devtools/common/options",
         "//src/main/protobuf:bundlemerge_java_proto",
diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcProvider.java b/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcProvider.java
index 127e5030a9..e4c13b0d58 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcProvider.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcProvider.java
@@ -38,9 +38,7 @@ import com.google.devtools.build.lib.rules.cpp.CcLinkingInfo;
 import com.google.devtools.build.lib.rules.cpp.CppModuleMap;
 import com.google.devtools.build.lib.rules.cpp.LinkerInputs;
 import com.google.devtools.build.lib.rules.cpp.LinkerInputs.LibraryToLink;
-import com.google.devtools.build.lib.skylarkinterface.SkylarkCallable;
-import com.google.devtools.build.lib.skylarkinterface.SkylarkModule;
-import com.google.devtools.build.lib.skylarkinterface.SkylarkModuleCategory;
+import com.google.devtools.build.lib.skylarkbuildapi.apple.ObjcProviderApi;
 import com.google.devtools.build.lib.syntax.EvalUtils;
 import com.google.devtools.build.lib.syntax.SkylarkNestedSet;
 import com.google.devtools.build.lib.syntax.SkylarkSemantics;
@@ -54,12 +52,7 @@ import java.util.Map;
  * deps that are needed for building Objective-C rules.
  */
 @Immutable
-@SkylarkModule(
-  name = "ObjcProvider",
-  category = SkylarkModuleCategory.PROVIDER,
-  doc = "A provider for compilation and linking of objc."
-)
-public final class ObjcProvider extends NativeInfo {
+public final class ObjcProvider extends NativeInfo implements ObjcProviderApi<Artifact> {
 
   /** Skylark name for the ObjcProvider. */
   public static final String SKYLARK_NAME = "objc";
@@ -427,341 +420,201 @@ public final class ObjcProvider extends NativeInfo {
           XCDATAMODEL,
           XIB);
 
-  @SkylarkCallable(name = "asset_catalog",
-      structField = true,
-      doc = "<b>Deprecated. Resource-related fields will be migrated to another provider.</b> "
-          + "Asset catalog resource files."
-  )
+  @Override
   public NestedSet<Artifact> assetCatalog() {
     return get(ASSET_CATALOG);
   }
 
-  @SkylarkCallable(name = "bundle_file",
-      structField = true,
-      doc = "<b>Deprecated. Resource-related fields will be migrated to another provider.</b> "
-          + "Files that are plopped into the final bundle at some arbitrary bundle path."
-  )
+  @Override
   public SkylarkNestedSet bundleFile() {
     return (SkylarkNestedSet) ObjcProviderSkylarkConverters.convertToSkylark(
         BUNDLE_FILE, get(BUNDLE_FILE));
   }
 
-  @SkylarkCallable(name = "define",
-      structField = true,
-      doc = "A set of strings from 'defines' attributes. These are to be passed as '-D' flags to "
-          + "all invocations of the compiler for this target and all depending targets."
-  )
+  @Override
   public NestedSet<String> define() {
     return get(DEFINE);
   }
 
-  @SkylarkCallable(name = "dynamic_framework_dir",
-      structField = true,
-      doc = "Exec paths of .framework directories corresponding to dynamic frameworks to link."
-  )
+  @Override
   public SkylarkNestedSet dynamicFrameworkDir() {
     return ObjcProviderSkylarkConverters.convertPathFragmentsToSkylark(get(DYNAMIC_FRAMEWORK_DIR));
   }
 
-  @SkylarkCallable(name = "dynamic_framework_file",
-      structField = true,
-      doc = "Files in .framework directories belonging to a dynamically linked framework."
-  )
+  @Override
   public NestedSet<Artifact> dynamicFrameworkFile() {
     return get(DYNAMIC_FRAMEWORK_FILE);
   }
 
-  @SkylarkCallable(name = "debug_symbols",
-      structField = true,
-      doc = "Files containing information on debug symbols."
-  )
+  @Override
   public NestedSet<Artifact> debugSymbols() {
     return get(DEBUG_SYMBOLS);
   }
 
-  @SkylarkCallable(name = "debug_symbols_plist",
-      structField = true,
-      doc = "Files containing the plist of the debug symbols."
-  )
+  @Override
   public NestedSet<Artifact> debugSymbolsPlist() {
     return get(DEBUG_SYMBOLS_PLIST);
   }
 
-  @SkylarkCallable(name = "exported_debug_artifacts",
-      structField = true,
-      doc = "Debug files that should be exported by the top-level target."
-  )
+  @Override
   public NestedSet<Artifact> exportedDebugArtifacts() {
     return get(EXPORTED_DEBUG_ARTIFACTS);
   }
 
-  @SkylarkCallable(name = "framework_search_path_only",
-      structField = true,
-      doc = "Exec paths of .framework directories corresponding to frameworks to include "
-          + "in search paths, but not to link."
-  )
+  @Override
   public SkylarkNestedSet frameworkSearchPathOnly() {
     return ObjcProviderSkylarkConverters.convertPathFragmentsToSkylark(
         get(FRAMEWORK_SEARCH_PATH_ONLY));
   }
 
-  @SkylarkCallable(name = "force_load_library",
-      structField = true,
-      doc = "Libraries to load with -force_load."
-  )
+  @Override
   public NestedSet<Artifact> forceLoadLibrary() {
     return get(FORCE_LOAD_LIBRARY);
   }
 
-  @SkylarkCallable(name = "header",
-      structField = true,
-      doc = "All header files. These may be either public or private headers."
-  )
+  @Override
   public NestedSet<Artifact> header() {
     return get(HEADER);
   }
 
-  @SkylarkCallable(name = "imported_library",
-      structField = true,
-      doc = "Imported precompiled static libraries (.a files) to be linked into the binary."
-  )
+  @Override
   public NestedSet<Artifact> importedLibrary() {
     return get(IMPORTED_LIBRARY);
   }
 
-  @SkylarkCallable(name = "include",
-      structField = true,
-      doc = "Include search paths specified with '-I' on the command line. Also known as "
-          + "header search paths (and distinct from <em>user</em> header search paths)."
-  )
+  @Override
   public SkylarkNestedSet include() {
     return ObjcProviderSkylarkConverters.convertPathFragmentsToSkylark(get(INCLUDE));
   }
 
-  @SkylarkCallable(name = "include_system",
-      structField = true,
-      doc = "System include search paths (typically specified with -isystem)."
-  )
+  @Override
   public SkylarkNestedSet includeSystem() {
     return ObjcProviderSkylarkConverters.convertPathFragmentsToSkylark(get(INCLUDE_SYSTEM));
   }
 
-  @SkylarkCallable(name = "iquote",
-      structField = true,
-      doc = "User header search paths (typically specified with -iquote)."
-  )
+  @Override
   public SkylarkNestedSet iquote() {
     return ObjcProviderSkylarkConverters.convertPathFragmentsToSkylark(get(IQUOTE));
   }
 
-  @SkylarkCallable(name = "j2objc_library",
-      structField = true,
-      doc = "Static libraries that are built from J2ObjC-translated Java code."
-  )
+  @Override
   public NestedSet<Artifact> j2objcLibrary() {
     return get(J2OBJC_LIBRARY);
   }
 
-  @SkylarkCallable(name = "jre_library",
-      structField = true,
-      doc = "J2ObjC JRE emulation libraries and their dependencies."
-  )
+  @Override
   public NestedSet<Artifact> jreLibrary() {
     return get(JRE_LIBRARY);
   }
 
-  @SkylarkCallable(name = "library",
-      structField = true,
-      doc = "Library (.a) files compiled by dependencies of the current target."
-  )
+  @Override
   public NestedSet<Artifact> library() {
     return get(LIBRARY);
   }
 
-  @SkylarkCallable(name = "link_inputs",
-      structField = true,
-      doc = "Link time artifacts from dependencies that do not fall into any other category such "
-          + "as libraries or archives. This catch-all provides a way to add arbitrary data (e.g. "
-          + "Swift AST files) to the linker. The rule that adds these is also responsible to "
-          + "add the necessary linker flags to 'linkopt'."
-  )
+  @Override
   public NestedSet<Artifact> linkInputs() {
     return get(LINK_INPUTS);
   }
 
-  @SkylarkCallable(name = "linked_binary",
-      structField = true,
-      doc = "Single-architecture linked binaries to be combined for the final multi-architecture "
-          + "binary."
-  )
+  @Override
   public NestedSet<Artifact> linkedBinary() {
     return get(LINKED_BINARY);
   }
 
-  @SkylarkCallable(name = "linkmap_file",
-      structField = true,
-      doc = "Single-architecture link map for a binary."
-  )
+  @Override
   public NestedSet<Artifact> linkmapFile() {
     return get(LINKMAP_FILE);
   }
 
-  @SkylarkCallable(name = "linkopt",
-      structField = true,
-      doc = "Linking options."
-  )
+  @Override
   public NestedSet<String> linkopt() {
     return get(LINKOPT);
   }
 
-  @SkylarkCallable(name = "merge_zip",
-      structField = true,
-      doc = "<b>Deprecated. Resource-related fields will be migrated to another provider.</b> "
-          + "Merge zips to include in the bundle. The entries of these zip files are included in "
-          + "the final bundle with the same path. The entries in the merge zips should not include "
-          + "the bundle root path (e.g. 'Foo.app')."
-  )
+  @Override
   public NestedSet<Artifact> mergeZip() {
     return get(MERGE_ZIP);
   }
 
-  @SkylarkCallable(name = "module_map",
-      structField = true,
-      doc = "Clang module maps, used to enforce proper use of private header files."
-  )
+  @Override
   public NestedSet<Artifact> moduleMap() {
     return get(MODULE_MAP);
   }
 
-  @SkylarkCallable(name = "multi_arch_dynamic_libraries",
-      structField = true,
-      doc = "Combined-architecture dynamic libraries to include in the final bundle."
-  )
+  @Override
   public NestedSet<Artifact> multiArchDynamicLibraries() {
     return get(MULTI_ARCH_DYNAMIC_LIBRARIES);
   }
 
-  @SkylarkCallable(name = "multi_arch_linked_archives",
-      structField = true,
-      doc = "Combined-architecture archives to include in the final bundle."
-  )
+  @Override
   public NestedSet<Artifact> multiArchLinkedArchives() {
     return get(MULTI_ARCH_LINKED_ARCHIVES);
   }
 
-  @SkylarkCallable(name = "multi_arch_linked_binaries",
-      structField = true,
-      doc = "Combined-architecture binaries to include in the final bundle."
-  )
+  @Override
   public NestedSet<Artifact> multiArchLinkedBinaries() {
     return get(MULTI_ARCH_LINKED_BINARIES);
   }
 
-  @SkylarkCallable(name = "root_merge_zip",
-      structField = true,
-      doc = "<b>Deprecated. Resource-related fields will be migrated to another provider.</b> "
-          + "Merge zips to include in the ipa and outside the bundle root."
-  )
+  @Override
   public NestedSet<Artifact> rootMergeZip() {
     return get(ROOT_MERGE_ZIP);
   }
 
-  @SkylarkCallable(name = "sdk_dylib",
-      structField = true,
-      doc = "Names of SDK .dylib libraries to link with. For instance, 'libz' or 'libarchive'."
-  )
+  @Override
   public NestedSet<String> sdkDylib() {
     return get(SDK_DYLIB);
   }
 
-  @SkylarkCallable(name = "sdk_framework",
-      structField = true,
-      doc = "Names of SDK frameworks to link with (e.g. 'AddressBook', 'QuartzCore')."
-  )
+  @Override
   public SkylarkNestedSet sdkFramework() {
     return (SkylarkNestedSet) ObjcProviderSkylarkConverters.convertToSkylark(SDK_FRAMEWORK,
         get(SDK_FRAMEWORK));
   }
 
-  @SkylarkCallable(name = "source",
-      structField = true,
-      doc = "All transitive source files."
-  )
+  @Override
   public NestedSet<Artifact> source() {
     return get(SOURCE);
   }
 
-  @SkylarkCallable(name = "static_framework_file",
-      structField = true,
-      doc = "Files in .framework directories that should be statically included as inputs "
-          + "when compiling and linking."
-  )
+  @Override
   public NestedSet<Artifact> staticFrameworkFile() {
     return get(STATIC_FRAMEWORK_FILE);
   }
 
-  @SkylarkCallable(name = "storyboard",
-      structField = true,
-      doc = "<b>Deprecated. Resource-related fields will be migrated to another provider.</b> "
-          + "Files for storyboard sources."
-  )
+  @Override
   public NestedSet<Artifact> storyboard() {
     return get(STORYBOARD);
   }
 
-  @SkylarkCallable(name = "strings",
-      structField = true,
-      doc = "<b>Deprecated. Resource-related fields will be migrated to another provider.</b> "
-          + "Files for strings source files."
-  )
+  @Override
   public NestedSet<Artifact> strings() {
     return get(STRINGS);
   }
 
-  @SkylarkCallable(name = "umbrella_header",
-      structField = true,
-      doc = "Clang umbrella header. Public headers are #included in umbrella headers to be "
-          + "compatible with J2ObjC segmented headers."
-  )
+  @Override
   public NestedSet<Artifact> umbrellaHeader() {
     return get(UMBRELLA_HEADER);
   }
 
-  @SkylarkCallable(name = "weak_sdk_framework",
-      structField = true,
-      doc = "Names of SDK frameworks to weakly link with. For instance, 'MediaAccessibility'. "
-           + "In difference to regularly linked SDK frameworks, symbols from weakly linked "
-           + "frameworks do not cause an error if they are not present at runtime."
-  )
+  @Override
   public SkylarkNestedSet weakSdkFramework() {
     return (SkylarkNestedSet) ObjcProviderSkylarkConverters.convertToSkylark(WEAK_SDK_FRAMEWORK,
         get(WEAK_SDK_FRAMEWORK));
   }
 
-  @SkylarkCallable(name = "xcassets_dir",
-      structField = true,
-      doc = "<b>Deprecated. Resource-related fields will be migrated to another provider.</b> "
-          + "The set of all unique asset catalog directories (*.xcassets) containing files "
-          + "in 'asset_catalogs'."
-  )
+  @Override
   public SkylarkNestedSet xcassetsDir() {
     return ObjcProviderSkylarkConverters.convertPathFragmentsToSkylark(get(XCASSETS_DIR));
   }
 
-  @SkylarkCallable(name = "xcdatamodel",
-      structField = true,
-      doc = "<b>Deprecated. Resource-related fields will be migrated to another provider.</b> "
-          + "Files that comprise the data models of the final linked binary."
-  )
+  @Override
   public NestedSet<Artifact> xcdatamodel() {
     return get(XCDATAMODEL);
   }
 
-  @SkylarkCallable(name = "xib",
-      structField = true,
-      doc = "<b>Deprecated. Resource-related fields will be migrated to another provider.</b> "
-          + ".xib resource files"
-  )
+  @Override
   public NestedSet<Artifact> xib() {
     return get(XIB);
   }
@@ -1073,12 +926,7 @@ public final class ObjcProvider extends NativeInfo {
    * Returns all unique static framework directories (directories ending in '.framework') for all
    * static framework files in this provider.
    */
-  @SkylarkCallable(
-      name = "framework_dir",
-      structField = true,
-      doc = "Returns all unique static framework directories (directories ending in '.framework') "
-          + "for all static framework files in this provider."
-  )
+  @Override
   public SkylarkNestedSet getStaticFrameworkDirsForSkylark() {
     return ObjcProviderSkylarkConverters.convertPathFragmentsToSkylark(getStaticFrameworkDirs());
   }
diff --git a/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/BUILD b/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/BUILD
index 85c2f407e3..000ac59e48 100644
--- a/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/BUILD
+++ b/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/BUILD
@@ -3,7 +3,7 @@
 #   (but not the implementation of that API). Ultimately, this package
 #   may be broken out of the Bazel package hierarchy to be standalone.
 #   Thus, this package should not depend on Bazel-specific packages (only
-#   those which contain pure-Skylark concepts, such as the interpretter or
+#   those which contain pure-Skylark concepts, such as the interpreter or
 #   annotation interfaces).
 
 package(default_visibility = ["//src:__subpackages__"])
diff --git a/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/SplitTransitionProviderApi.java b/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/SplitTransitionProviderApi.java
new file mode 100644
index 0000000000..4d32910345
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/SplitTransitionProviderApi.java
@@ -0,0 +1,22 @@
+// Copyright 2018 The Bazel Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//    http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.devtools.build.lib.skylarkbuildapi;
+
+/**
+ * Interface for a type representing a split configuration transition.
+ */
+public interface SplitTransitionProviderApi {
+  // TODO(cparsons): Expose this explicitly to the build API.
+}
diff --git a/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/apple/AppleBitcodeModeApi.java b/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/apple/AppleBitcodeModeApi.java
new file mode 100644
index 0000000000..4a70e110d2
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/apple/AppleBitcodeModeApi.java
@@ -0,0 +1,36 @@
+// Copyright 2018 The Bazel Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//    http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.devtools.build.lib.skylarkbuildapi.apple;
+
+import com.google.devtools.build.lib.skylarkinterface.SkylarkModule;
+import com.google.devtools.build.lib.skylarkinterface.SkylarkModuleCategory;
+import com.google.devtools.build.lib.skylarkinterface.SkylarkValue;
+
+/**
+ * Interface for an enum describing the bitcode mode to use when compiling Objective-C and Swift
+ * code on Apple platforms.
+ */
+@SkylarkModule(
+  name = "apple_bitcode_mode",
+  category = SkylarkModuleCategory.NONE,
+  doc =
+      "The Bitcode mode to use when compiling Objective-C and Swift code on Apple platforms. "
+          + "Possible values are:<br><ul>"
+          + "<li><code>'none'</code></li>"
+          + "<li><code>'embedded'</code></li>"
+          + "<li><code>'embedded_markers'</code></li>"
+          + "</ul>"
+)
+public interface AppleBitcodeModeApi extends SkylarkValue {}
diff --git a/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/apple/AppleCommonApi.java b/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/apple/AppleCommonApi.java
new file mode 100644
index 0000000000..6f547e4bf4
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/apple/AppleCommonApi.java
@@ -0,0 +1,371 @@
+// Copyright 2018 The Bazel Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//    http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.devtools.build.lib.skylarkbuildapi.apple;
+
+import com.google.common.collect.ImmutableMap;
+import com.google.devtools.build.lib.skylarkbuildapi.FileApi;
+import com.google.devtools.build.lib.skylarkbuildapi.ProviderApi;
+import com.google.devtools.build.lib.skylarkbuildapi.SkylarkAspectApi;
+import com.google.devtools.build.lib.skylarkbuildapi.SkylarkRuleContextApi;
+import com.google.devtools.build.lib.skylarkbuildapi.SplitTransitionProviderApi;
+import com.google.devtools.build.lib.skylarkbuildapi.StructApi;
+import com.google.devtools.build.lib.skylarkbuildapi.apple.AppleStaticLibraryInfoApi.AppleStaticLibraryInfoProvider;
+import com.google.devtools.build.lib.skylarkinterface.Param;
+import com.google.devtools.build.lib.skylarkinterface.SkylarkCallable;
+import com.google.devtools.build.lib.skylarkinterface.SkylarkModule;
+import com.google.devtools.build.lib.syntax.Environment;
+import com.google.devtools.build.lib.syntax.EvalException;
+import com.google.devtools.build.lib.syntax.SkylarkDict;
+import com.google.devtools.build.lib.syntax.SkylarkNestedSet;
+
+/**
+ * Interface for a module with useful functions for creating apple-related rule implementations.
+ */
+@SkylarkModule(
+    name = "apple_common",
+    doc = "Functions for skylark to access internals of the apple rule implementations."
+)
+public interface AppleCommonApi<FileApiT extends FileApi,
+    ObjcProviderApiT extends ObjcProviderApi<?>,
+    XcodeConfigProviderApiT extends XcodeConfigProviderApi<?, ?>,
+    ApplePlatformApiT extends ApplePlatformApi> {
+
+  @SkylarkCallable(
+      name = "apple_toolchain",
+      doc = "Utilities for resolving items from the apple toolchain."
+  )
+  public AppleToolchainApi<?> getAppleToolchain();
+
+  @SkylarkCallable(
+    name = "platform_type",
+    doc =
+        "An enum-like struct that contains the following fields corresponding to Apple platform "
+            + "types:<br><ul>"
+            + "<li><code>ios</code></li>"
+            + "<li><code>macos</code></li>"
+            + "<li><code>tvos</code></li>"
+            + "<li><code>watchos</code></li>"
+            + "</ul><p>"
+            + "These values can be passed to methods that expect a platform type, like the 'apple' "
+            + "configuration fragment's "
+            + "<a href='apple.html#multi_arch_platform'>multi_arch_platform</a> method.<p>"
+            + "Example:<p>"
+            + "<pre class='language-python'>\n"
+            + "ctx.fragments.apple.multi_arch_platform(apple_common.platform_type.ios)\n"
+            + "</pre>",
+    structField = true
+  )
+  public StructApi getPlatformTypeStruct();
+
+  @SkylarkCallable(
+    name = "platform",
+    doc =
+        "An enum-like struct that contains the following fields corresponding to Apple "
+            + "platforms:<br><ul>"
+            + "<li><code>ios_device</code></li>"
+            + "<li><code>ios_simulator</code></li>"
+            + "<li><code>macos</code></li>"
+            + "<li><code>tvos_device</code></li>"
+            + "<li><code>tvos_simulator</code></li>"
+            + "<li><code>watchos_device</code></li>"
+            + "<li><code>watchos_device</code></li>"
+            + "</ul><p>"
+            + "These values can be passed to methods that expect a platform, like "
+            + "<a href='apple.html#sdk_version_for_platform'>apple.sdk_version_for_platform</a>.",
+    structField = true
+  )
+  public StructApi getPlatformStruct();
+
+  @SkylarkCallable(
+    name = "XcodeProperties",
+    doc =
+        "The constructor/key for the <code>XcodeVersionProperties</code> provider.<p>"
+            + "If a target propagates the <code>XcodeVersionProperties</code> provider,"
+            + " use this as the key with which to retrieve it. Example:<br>"
+            + "<pre class='language-python'>\n"
+            + "dep = ctx.attr.deps[0]\n"
+            + "p = dep[apple_common.XcodeVersionProperties]\n"
+            + "</pre>",
+    structField = true
+  )
+  public ProviderApi getXcodeVersionPropertiesConstructor();
+
+  @SkylarkCallable(
+      name = "XcodeVersionConfig",
+      doc = "The constructor/key for the <code>XcodeVersionConfig</code> provider.",
+      structField =  true
+  )
+  public ProviderApi getXcodeVersionConfigConstructor();
+
+  @SkylarkCallable(
+    // TODO(b/63899207): This currently does not match ObjcProvider.SKYLARK_NAME as it requires
+    // a migration of existing skylark rules.
+    name = "Objc",
+    doc =
+        "The constructor/key for the <code>Objc</code> provider.<p>"
+            + "If a target propagates the <code>Objc</code> provider, use this as the "
+            + "key with which to retrieve it. Example:<br>"
+            + "<pre class='language-python'>\n"
+            + "dep = ctx.attr.deps[0]\n"
+            + "p = dep[apple_common.Objc]\n"
+            + "</pre>",
+    structField = true
+  )
+  public ProviderApi getObjcProviderConstructor();
+
+  @SkylarkCallable(
+    name = "AppleDynamicFramework",
+    doc =
+        "The constructor/key for the <code>AppleDynamicFramework</code> provider.<p>"
+            + "If a target propagates the <code>AppleDynamicFramework</code> provider, use this "
+            + "as the key with which to retrieve it. Example:<br>"
+            + "<pre class='language-python'>\n"
+            + "dep = ctx.attr.deps[0]\n"
+            + "p = dep[apple_common.AppleDynamicFramework]\n"
+            + "</pre>",
+    structField = true
+  )
+  public ProviderApi getAppleDynamicFrameworkConstructor();
+
+  @SkylarkCallable(
+    name = "AppleDylibBinary",
+    doc =
+        "The constructor/key for the <code>AppleDylibBinary</code> provider.<p>"
+            + "If a target propagates the <code>AppleDylibBinary</code> provider, use this as the "
+            + "key with which to retrieve it. Example:<br>"
+            + "<pre class='language-python'>\n"
+            + "dep = ctx.attr.deps[0]\n"
+            + "p = dep[apple_common.AppleDylibBinary]\n"
+            + "</pre>",
+    structField = true
+  )
+  public ProviderApi getAppleDylibBinaryConstructor();
+
+  @SkylarkCallable(
+    name = "AppleExecutableBinary",
+    doc =
+        "The constructor/key for the <code>AppleExecutableBinary</code> provider.<p>"
+            + "If a target propagates the <code>AppleExecutableBinary</code> provider,"
+            + " use this as the key with which to retrieve it. Example:<br>"
+            + "<pre class='language-python'>\n"
+            + "dep = ctx.attr.deps[0]\n"
+            + "p = dep[apple_common.AppleExecutableBinary]\n"
+            + "</pre>",
+    structField = true
+  )
+  public ProviderApi getAppleExecutableBinaryConstructor();
+
+  @SkylarkCallable(
+    name = "AppleStaticLibrary",
+    doc =
+        "The constructor/key for the <code>AppleStaticLibrary</code> provider.<p>"
+            + "If a target propagates the <code>AppleStaticLibrary</code> provider, use "
+            + "this as the key with which to retrieve it. Example:<br>"
+            + "<pre class='language-python'>\n"
+            + "dep = ctx.attr.deps[0]\n"
+            + "p = dep[apple_common.AppleStaticLibrary]\n"
+            + "</pre>",
+    structField = true
+  )
+  public AppleStaticLibraryInfoProvider<?, ?> getAppleStaticLibraryProvider();
+
+  @SkylarkCallable(
+    name = "AppleDebugOutputs",
+    doc =
+        "The constructor/key for the <code>AppleDebugOutputs</code> provider.<p>"
+            + "If a target propagates the <code>AppleDebugOutputs</code> provider, use this as the "
+            + "key with which to retrieve it. Example:<br>"
+            + "<pre class='language-python'>\n"
+            + "dep = ctx.attr.deps[0]\n"
+            + "p = dep[apple_common.AppleDebugOutputs]\n"
+            + "</pre>",
+    structField = true
+  )
+  public ProviderApi getAppleDebugOutputsConstructor();
+
+  @SkylarkCallable(
+    name = "AppleLoadableBundleBinary",
+    doc =
+        "The constructor/key for the <code>AppleLoadableBundleBinary</code> provider.<p>"
+            + "If a target propagates the <code>AppleLoadableBundleBinary</code> provider, "
+            + "use this as the key with which to retrieve it. Example:<br>"
+            + "<pre class='language-python'>\n"
+            + "dep = ctx.attr.deps[0]\n"
+            + "p = dep[apple_common.AppleLoadableBundleBinary]\n"
+            + "</pre>",
+    structField = true
+  )
+  public ProviderApi getAppleLoadableBundleBinaryConstructor();
+
+  @SkylarkCallable(
+      name = "apple_host_system_env",
+      doc =
+          "Returns a <a href='dict.html'>dict</a> of environment variables that should be set "
+              + "for actions that need to run build tools on an Apple host system, such as the "
+              + " version of Xcode that should be used. The keys are variable names and the values "
+              + " are their corresponding values."
+  )
+  public ImmutableMap<String, String> getAppleHostSystemEnv(
+      XcodeConfigProviderApiT xcodeConfig);
+
+  @SkylarkCallable(
+      name = "target_apple_env",
+      doc =
+          "Returns a <code>dict</code> of environment variables that should be set for actions "
+              + "that build targets of the given Apple platform type. For example, this dictionary "
+              + "contains variables that denote the platform name and SDK version with which to "
+              + "build. The keys are variable names and the values are their corresponding values."
+  )
+  public ImmutableMap<String, String> getTargetAppleEnvironment(
+      XcodeConfigProviderApiT xcodeConfig, ApplePlatformApiT platform);
+
+  @SkylarkCallable(
+      name = "multi_arch_split",
+      doc = "A configuration transition for rule attributes to build dependencies in one or"
+          + " more Apple platforms. "
+          + "<p>Use of this transition requires that the 'platform_type' and 'minimum_os_version'"
+          + " string attributes are defined and mandatory on the rule.</p>"
+          + "<p>The value of the platform_type attribute will dictate the target architectures "
+          + " for which dependencies along this configuration transition will be built.</p>"
+          + "<p>Options are:</p>"
+          + "<ul>"
+          + "<li><code>ios</code>: architectures gathered from <code>--ios_multi_cpus</code>.</li>"
+          + "<li><code>macos</code>: architectures gathered from <code>--macos_cpus</code>.</li>"
+          + "<li><code>tvos</code>: architectures gathered from <code>--tvos_cpus</code>.</li>"
+          + "<li><code>watchos</code>: architectures gathered from <code>--watchos_cpus</code>."
+          + "</li></ul>"
+          + "<p>minimum_os_version should be a dotted version string such as '7.3', and is used to"
+          + " set the minimum operating system on the configuration similarly based on platform"
+          + " type. For example, specifying platform_type 'ios' and minimum_os_version '8.0' will"
+          + " ensure that dependencies are built with minimum iOS version '8.0'.",
+      structField = true
+  )
+  public SplitTransitionProviderApi getMultiArchSplitProvider();
+
+  @SkylarkCallable(
+    name = "new_objc_provider",
+    doc = "Creates a new ObjcProvider instance.",
+    parameters = {
+      @Param(
+        name = "uses_swift",
+        type = Boolean.class,
+        defaultValue = "False",
+        named = true,
+        positional = false,
+        doc = "Whether this provider should enable Swift support."
+      )
+    },
+    extraKeywords =
+        @Param(
+          name = "kwargs",
+          type = SkylarkDict.class,
+          defaultValue = "{}",
+          doc = "Dictionary of arguments."
+        ),
+    useEnvironment = true
+  )
+  // This method is registered statically for skylark, and never called directly.
+  public ObjcProviderApi<?> newObjcProvider(
+      Boolean usesSwift,
+      SkylarkDict<?, ?> kwargs,
+      Environment environment);
+
+  @SkylarkCallable(
+    name = "new_dynamic_framework_provider",
+    doc = "Creates a new AppleDynamicFramework provider instance.",
+    parameters = {
+      @Param(
+        name = "binary",
+        type = FileApi.class,
+        named = true,
+        positional = false,
+        doc = "The dylib binary artifact of the dynamic framework."
+      ),
+      @Param(
+        name = "objc",
+        type = ObjcProviderApi.class,
+        named = true,
+        positional = false,
+        doc =
+            "An ObjcProvider which contains information about the transitive "
+                + "dependencies linked into the binary."
+      ),
+      @Param(
+        name = "framework_dirs",
+        type = SkylarkNestedSet.class,
+        generic1 = String.class,
+        named = true,
+        noneable = true,
+        positional = false,
+        defaultValue = "None",
+        doc =
+            "The framework path names used as link inputs in order to link against the dynamic "
+                + "framework."
+      ),
+      @Param(
+        name = "framework_files",
+        type = SkylarkNestedSet.class,
+        generic1 = FileApi.class,
+        named = true,
+        noneable = true,
+        positional = false,
+        defaultValue = "None",
+        doc =
+            "The full set of artifacts that should be included as inputs to link against the "
+                + "dynamic framework"
+      )
+    }
+  )
+  public AppleDynamicFrameworkInfoApi<?, ?> newDynamicFrameworkProvider(
+      FileApiT dylibBinary,
+      ObjcProviderApiT depsObjcProvider,
+      Object dynamicFrameworkDirs,
+      Object dynamicFrameworkFiles);
+
+  @SkylarkCallable(
+      name = "link_multi_arch_binary",
+      doc = "Links a (potentially multi-architecture) binary targeting Apple platforms. This "
+          + "method comprises a bulk of the logic of the <code>apple_binary</code> rule, and is "
+          + "exposed as an API to iterate on migration of <code>apple_binary</code> to skylark.\n"
+          + "<p>This API is <b>highly experimental</b> and subject to change at any time. Do not "
+          + "depend on the stability of this function at this time.",
+      mandatoryPositionals = 1 // The SkylarkRuleContext.
+  )
+  // TODO(b/70937317): Iterate on, improve, and solidify this API.
+  public StructApi linkMultiArchBinary(SkylarkRuleContextApi skylarkRuleContext)
+      throws EvalException, InterruptedException;
+
+  @SkylarkCallable(
+    name = "dotted_version",
+    doc = "Creates a new <a href=\"DottedVersion.html\">DottedVersion</a> instance.",
+    parameters = {
+      @Param(
+        name = "version",
+        type = String.class,
+        doc = "The string representation of the DottedVersion."
+      )
+    }
+  )
+  public DottedVersionApi<?> dottedVersion(String version);
+
+  @SkylarkCallable(
+    name = "objc_proto_aspect",
+    doc =
+        "objc_proto_aspect gathers the proto dependencies of the attached rule target,"
+            + "and propagates the proto values of its dependencies through the ObjcProto provider.",
+    structField = true
+  )
+  public SkylarkAspectApi getObjcProtoAspect();
+}
diff --git a/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/apple/AppleConfigurationApi.java b/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/apple/AppleConfigurationApi.java
new file mode 100644
index 0000000000..03fac8476e
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/apple/AppleConfigurationApi.java
@@ -0,0 +1,78 @@
+// Copyright 2018 The Bazel Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//    http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.devtools.build.lib.skylarkbuildapi.apple;
+
+import com.google.devtools.build.lib.skylarkinterface.SkylarkCallable;
+import com.google.devtools.build.lib.skylarkinterface.SkylarkModule;
+import com.google.devtools.build.lib.skylarkinterface.SkylarkModuleCategory;
+
+/** An interface for a configuration type containing info for Apple platforms and tools. */
+@SkylarkModule(
+    name = "apple",
+    doc = "A configuration fragment for Apple platforms.",
+    category = SkylarkModuleCategory.CONFIGURATION_FRAGMENT
+)
+public interface AppleConfigurationApi<ApplePlatformTypeApiT extends ApplePlatformTypeApi> {
+
+  @SkylarkCallable(
+      name = "ios_cpu",
+      doc = "<b>Deprecated. Use <a href='#single_arch_cpu'>single_arch_cpu</a> instead.</b> "
+          + "The value of ios_cpu for this configuration.")
+  public String getIosCpu();
+
+  @SkylarkCallable(
+    name = "single_arch_cpu",
+    structField = true,
+    doc =
+        "The single \"effective\" architecture for this configuration (e.g., <code>i386</code> or "
+            + "<code>arm64</code>) in the context of rule logic that is only concerned with a "
+            + "single architecture (such as <code>objc_library</code>, which registers "
+            + "single-architecture compile actions)."
+  )
+  public String getSingleArchitecture();
+
+  @SkylarkCallable(
+    name = "single_arch_platform",
+    doc = "The platform of the current configuration. This should only be invoked in a context "
+        + "where only a single architecture may be supported; consider "
+        + "<a href='#multi_arch_platform'>multi_arch_platform</a> for other cases.",
+    structField = true
+  )
+  public ApplePlatformApi getSingleArchPlatform();
+
+  @SkylarkCallable(
+    name = "multi_arch_platform",
+    doc = "The platform of the current configuration for the given platform type. This should only "
+        + "be invoked in a context where multiple architectures may be supported; consider "
+        + "<a href='#single_arch_platform'>single_arch_platform</a> for other cases."
+  )
+  public ApplePlatformApi getMultiArchPlatform(ApplePlatformTypeApiT platformType);
+
+  @SkylarkCallable(
+      name = "ios_cpu_platform",
+      doc = "<b>Deprecated. Use <a href='#single_arch_platform'>single_arch_platform</a> or "
+          + "<a href='#multi_arch_platform'>multi_arch_platform</a> instead.</b> "
+          + "The platform given by the ios_cpu flag.")
+  public ApplePlatformApi getIosCpuPlatform();
+
+  @SkylarkCallable(
+    name = "bitcode_mode",
+    doc = "Returns the Bitcode mode to use for compilation steps.<p>"
+        + "This field is only valid for device builds; for simulator builds, it always returns "
+        + "<code>'none'</code>.",
+    structField = true
+  )
+  public AppleBitcodeModeApi getBitcodeMode();
+}
diff --git a/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/apple/AppleDynamicFrameworkInfoApi.java b/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/apple/AppleDynamicFrameworkInfoApi.java
new file mode 100644
index 0000000000..805b4506fc
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/apple/AppleDynamicFrameworkInfoApi.java
@@ -0,0 +1,81 @@
+// Copyright 2018 The Bazel Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//    http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.devtools.build.lib.skylarkbuildapi.apple;
+
+import com.google.devtools.build.lib.collect.nestedset.NestedSet;
+import com.google.devtools.build.lib.skylarkbuildapi.FileApi;
+import com.google.devtools.build.lib.skylarkbuildapi.StructApi;
+import com.google.devtools.build.lib.skylarkinterface.SkylarkCallable;
+import com.google.devtools.build.lib.skylarkinterface.SkylarkModule;
+import com.google.devtools.build.lib.skylarkinterface.SkylarkModuleCategory;
+import javax.annotation.Nullable;
+
+/**
+ * An interface representing an info type containing information about an Apple dynamic
+ * framework.
+ **/
+@SkylarkModule(
+    name = "AppleDynamicFramework",
+    category = SkylarkModuleCategory.PROVIDER,
+    doc = "A provider containing information about an Apple dynamic framework."
+)
+public interface AppleDynamicFrameworkInfoApi<PathFragmentT, FileApiT extends FileApi>
+    extends StructApi {
+
+  /**
+   * Returns the framework path names used as link inputs in order to link against the dynamic
+   * framework.
+   */
+  @SkylarkCallable(name = "framework_dirs",
+      structField = true,
+      doc = "The framework path names used as link inputs in order to link against the dynamic "
+          + "framework."
+  )
+  public NestedSet<PathFragmentT> getDynamicFrameworkDirs();
+
+  /**
+   * Returns the full set of artifacts that should be included as inputs to link against the
+   * dynamic framework.
+   */
+  @SkylarkCallable(name = "framework_files",
+      structField = true,
+      doc = "The full set of files that should be included as inputs to link against the "
+          + "dynamic framework."
+  )
+  public NestedSet<FileApiT> getDynamicFrameworkFiles();
+
+  /**
+   * Returns the multi-architecture dylib binary of the dynamic framework. May return null if
+   * the rule providing the framework only specified framework imports.
+   */
+  @Nullable
+  @SkylarkCallable(name = "binary",
+      structField = true,
+      doc = "The multi-architecture dylib binary of the dynamic framework. May be null if "
+          + "the rule providing the framework only specified framework imports."
+  )
+  public FileApi getAppleDylibBinary();
+
+  /**
+   * Returns the {@link ObjcProviderApi} which contains information about the transitive
+   * dependencies linked into the dylib.
+   */
+  @SkylarkCallable(name = "objc",
+      structField = true,
+      doc = "A provider which contains information about the transitive dependencies linked into "
+          + "the dynamic framework."
+  )
+  public ObjcProviderApi<FileApiT> getDepsObjcProvider();
+}
diff --git a/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/apple/ApplePlatformApi.java b/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/apple/ApplePlatformApi.java
new file mode 100644
index 0000000000..1c4aeae028
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/apple/ApplePlatformApi.java
@@ -0,0 +1,83 @@
+// Copyright 2018 The Bazel Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//    http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.devtools.build.lib.skylarkbuildapi.apple;
+
+import com.google.devtools.build.lib.skylarkinterface.SkylarkCallable;
+import com.google.devtools.build.lib.skylarkinterface.SkylarkModule;
+import com.google.devtools.build.lib.skylarkinterface.SkylarkModuleCategory;
+import com.google.devtools.build.lib.skylarkinterface.SkylarkValue;
+
+/** An interface for an object representing an Apple platform. */
+@SkylarkModule(
+    name = "apple_platform",
+    category = SkylarkModuleCategory.NONE,
+    doc = "Corresponds to Xcode's notion of a platform as would be found in "
+        + "<code>Xcode.app/Contents/Developer/Platforms</code>. Each platform represents an Apple "
+        + "platform type (such as iOS or tvOS) combined with one or more related CPU "
+        + "architectures. For example, the iOS simulator platform supports <code>x86_64</code> and "
+        + "<code>i386</code> architectures.<p>"
+        + "Specific instances of this type can be retrieved from the fields of the "
+        + "<a href='apple_common.html#platform'>apple_common.platform</a> struct:<br><ul>"
+        + "<li><code>apple_common.platform.ios_device</code></li>"
+        + "<li><code>apple_common.platform.ios_simulator</code></li>"
+        + "<li><code>apple_common.platform.macos</code></li>"
+        + "<li><code>apple_common.platform.tvos_device</code></li>"
+        + "<li><code>apple_common.platform.tvos_simulator</code></li>"
+        + "<li><code>apple_common.platform.watchos_device</code></li>"
+        + "<li><code>apple_common.platform.watchos_simulator</code></li>"
+        + "</ul><p>"
+        + "More commonly, however, the <a href='apple.html'>apple</a> configuration fragment has "
+        + "fields/methods that allow rules to determine the platform for which a target is being "
+        + "built.<p>"
+        + "Example:<br>"
+        + "<pre class='language-python'>\n"
+        + "p = apple_common.platform.ios_device\n"
+        + "print(p.name_in_plist)  # 'iPhoneOS'\n"
+        + "</pre>"
+)
+public interface ApplePlatformApi extends SkylarkValue {
+
+  /** Returns the platform type of this platform. */
+  @SkylarkCallable(
+      name = "platform_type",
+      doc = "Returns the platform type of this platform.",
+      structField = true
+  )
+  public ApplePlatformTypeApi getType();
+
+  /**
+   * Returns true if this platform is a device platform, or false if this is a simulator platform.
+   */
+  @SkylarkCallable(
+      name = "is_device",
+      doc = "Returns <code>True</code> if this platform is a device platform or <code>False</code> "
+          + "if it is a simulator platform.",
+      structField = true
+  )
+  public boolean isDevice();
+
+  /**
+   * Returns the name of the "platform" as it appears in the CFBundleSupportedPlatforms plist
+   * setting.
+   */
+  @SkylarkCallable(name = "name_in_plist", structField = true,
+      doc = "The name of the platform as it appears in the <code>CFBundleSupportedPlatforms</code> "
+          + "entry of an Info.plist file and in Xcode's platforms directory, without the extension "
+          + "(for example, <code>iPhoneOS</code> or <code>iPhoneSimulator</code>).<br>"
+          + "This name, when converted to lowercase (e.g., <code>iphoneos</code>, "
+          + "<code>iphonesimulator</code>), can be passed to Xcode's command-line tools like "
+          + "<code>ibtool</code> and <code>actool</code> when they expect a platform name.")
+  public String getNameInPlist();
+}
diff --git a/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/apple/ApplePlatformTypeApi.java b/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/apple/ApplePlatformTypeApi.java
new file mode 100644
index 0000000000..f724bdba1e
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/apple/ApplePlatformTypeApi.java
@@ -0,0 +1,42 @@
+// Copyright 2018 The Bazel Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//    http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.devtools.build.lib.skylarkbuildapi.apple;
+
+import com.google.devtools.build.lib.skylarkinterface.SkylarkModule;
+import com.google.devtools.build.lib.skylarkinterface.SkylarkModuleCategory;
+import com.google.devtools.build.lib.skylarkinterface.SkylarkValue;
+
+/**
+ * Interface for a descriptor for an Apple platform type, such as such as iOS or macOS.
+ */
+@SkylarkModule(
+  name = "apple_platform_type",
+  category = SkylarkModuleCategory.NONE,
+  doc = "Describes an Apple \"platform type\", such as iOS, macOS, tvOS, or watchOS. This is "
+      + "distinct from a \"platform\", which is the platform type combined with one or more CPU "
+      + "architectures.<p>"
+      + "Specific instances of this type can be retrieved by accessing the fields of the "
+      + "<a href='apple_common.html#platform_type'>apple_common.platform_type</a>:<br><ul>"
+      + "<li><code>apple_common.platform_type.ios</code></li>"
+      + "<li><code>apple_common.platform_type.macos</code></li>"
+      + "<li><code>apple_common.platform_type.tvos</code></li>"
+      + "<li><code>apple_common.platform_type.watchos</code></li>"
+      + "</ul><p>"
+      + "Likewise, the platform type of an existing platform value can be retrieved using its "
+      + "<code>platform_type</code> field.<p>"
+      + "Platform types can be converted to a lowercase string (e.g., <code>ios</code> or "
+      + "<code>macos</code>) using the <a href='globals.html#str'>str</a> function."
+)
+public interface ApplePlatformTypeApi extends SkylarkValue {}
diff --git a/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/apple/AppleStaticLibraryInfoApi.java b/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/apple/AppleStaticLibraryInfoApi.java
new file mode 100644
index 0000000000..fdcdb7bf6d
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/apple/AppleStaticLibraryInfoApi.java
@@ -0,0 +1,84 @@
+// Copyright 2018 The Bazel Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//    http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.devtools.build.lib.skylarkbuildapi.apple;
+
+import com.google.devtools.build.lib.skylarkbuildapi.FileApi;
+import com.google.devtools.build.lib.skylarkbuildapi.ProviderApi;
+import com.google.devtools.build.lib.skylarkbuildapi.StructApi;
+import com.google.devtools.build.lib.skylarkinterface.Param;
+import com.google.devtools.build.lib.skylarkinterface.SkylarkCallable;
+import com.google.devtools.build.lib.skylarkinterface.SkylarkConstructor;
+import com.google.devtools.build.lib.skylarkinterface.SkylarkModule;
+import com.google.devtools.build.lib.skylarkinterface.SkylarkModuleCategory;
+import com.google.devtools.build.lib.syntax.EvalException;
+
+/**
+ * Interface for an info type containing information regarding multi-architecture Apple static
+ * libraries.
+ */
+@SkylarkModule(
+    name = "AppleStaticLibrary",
+    category = SkylarkModuleCategory.PROVIDER,
+    doc = "A provider containing information regarding multi-architecture Apple static libraries, "
+        + "as is propagated by the apple_static_library rule."
+)
+public interface AppleStaticLibraryInfoApi extends StructApi {
+
+  /** Skylark name for this interface. */
+  public static final String SKYLARK_NAME = "AppleStaticLibrary";
+
+  @SkylarkCallable(name = "archive",
+      structField = true,
+      doc = "The multi-arch archive (.a) output by apple_static_library."
+  )
+  public FileApi getMultiArchArchive();
+
+  @SkylarkCallable(name = "objc",
+      structField = true,
+      doc = "A provider which contains information about the transitive dependencies linked into "
+          + "the archive."
+  )
+  public ObjcProviderApi<?> getDepsObjcProvider();
+
+  /**
+   * Interface for the provider type for {@link AppleStaticLibraryInfoApi}.
+   */
+  public interface AppleStaticLibraryInfoProvider<FileApiT extends FileApi,
+      ObjcProviderApiT extends ObjcProviderApi<?>> extends ProviderApi {
+
+    @SkylarkCallable(
+        name = SKYLARK_NAME,
+        doc = "The <code>AppleStaticLibrary</code> constructor.",
+        parameters = {
+            @Param(
+                name = "archive",
+                type = FileApi.class,
+                named = true,
+                positional = false,
+                doc = "Multi-architecture archive (.a) representing a static library"),
+            @Param(
+                name = "objc",
+                type = ObjcProviderApi.class,
+                named = true,
+                positional = false,
+                doc = "A provider which contains information about the transitive dependencies "
+                    + "linked into the archive."),
+        },
+        selfCall = true)
+    @SkylarkConstructor(objectType = AppleStaticLibraryInfoApi.class)
+    public AppleStaticLibraryInfoApi appleStaticLibrary(
+        FileApiT archive, ObjcProviderApiT objcProvider) throws EvalException;
+  }
+}
diff --git a/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/apple/AppleToolchainApi.java b/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/apple/AppleToolchainApi.java
new file mode 100644
index 0000000000..7481a97010
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/apple/AppleToolchainApi.java
@@ -0,0 +1,46 @@
+// Copyright 2018 The Bazel Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//    http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.devtools.build.lib.skylarkbuildapi.apple;
+
+import com.google.devtools.build.lib.skylarkinterface.SkylarkCallable;
+import com.google.devtools.build.lib.skylarkinterface.SkylarkModule;
+
+/**
+ * Interface for a utility module involving the Apple toolchain.
+ */
+@SkylarkModule(
+    name = "apple_toolchain",
+    doc = "Utilities for resolving items from the Apple toolchain."
+)
+public interface AppleToolchainApi<AppleConfigurationApiT extends AppleConfigurationApi<?>> {
+
+  @SkylarkCallable(
+    name = "sdk_dir",
+    doc = "Returns the platform directory inside of Xcode for a given configuration."
+  )
+  public String sdkDirConstant();
+
+  @SkylarkCallable(
+    name = "developer_dir",
+    doc = "Returns the Developer directory inside of Xcode for a given configuration."
+  )
+  public String developerDirConstant();
+
+  @SkylarkCallable(
+    name = "platform_developer_framework_dir",
+    doc = "Returns the platform frameworks directory inside of Xcode for a given configuration."
+  )
+  public String platformFrameworkDirFromConfig(AppleConfigurationApiT configuration);
+}
diff --git a/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/apple/BUILD b/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/apple/BUILD
new file mode 100644
index 0000000000..f4cc1b4d93
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/apple/BUILD
@@ -0,0 +1,30 @@
+# Description:
+#   This package contains interfaces representing the skylark "build API"
+#   (but not the implementation of that API). Ultimately, this package
+#   may be broken out of the Bazel package hierarchy to be standalone.
+#   Thus, this package should not depend on Bazel-specific packages (only
+#   those which contain pure-Skylark concepts, such as the interpreter or
+#   annotation interfaces).
+
+package(default_visibility = ["//src:__subpackages__"])
+
+licenses(["notice"])  # Apache 2.0
+
+filegroup(
+    name = "srcs",
+    srcs = glob(["**"]),
+)
+
+java_library(
+    name = "apple",
+    srcs = glob(["*.java"]),
+    deps = [
+        "//src/main/java/com/google/devtools/build/lib:skylarkinterface",
+        "//src/main/java/com/google/devtools/build/lib:syntax",
+        "//src/main/java/com/google/devtools/build/lib/cmdline",
+        "//src/main/java/com/google/devtools/build/lib/collect/nestedset",
+        "//src/main/java/com/google/devtools/build/lib/skylarkbuildapi",
+        "//third_party:guava",
+        "//third_party:jsr305",
+    ],
+)
diff --git a/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/apple/DottedVersionApi.java b/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/apple/DottedVersionApi.java
new file mode 100644
index 0000000000..609609d6c6
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/apple/DottedVersionApi.java
@@ -0,0 +1,43 @@
+// Copyright 2018 The Bazel Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//    http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.devtools.build.lib.skylarkbuildapi.apple;
+
+import com.google.devtools.build.lib.skylarkinterface.SkylarkCallable;
+import com.google.devtools.build.lib.skylarkinterface.SkylarkModule;
+import com.google.devtools.build.lib.skylarkinterface.SkylarkModuleCategory;
+import com.google.devtools.build.lib.skylarkinterface.SkylarkValue;
+
+/**
+ * Interface for a value representing a version with multiple components, separated by periods,
+ * such as "1.2.3.4".
+ **/
+@SkylarkModule(
+    name = "DottedVersion",
+    category = SkylarkModuleCategory.NONE,
+    doc =
+        "A value representing a version with multiple components, separated by periods, such as "
+            + "1.2.3.4."
+)
+public interface DottedVersionApi<SelfT extends DottedVersionApi<?>>
+    extends SkylarkValue, Comparable<SelfT> {
+
+  @SkylarkCallable(
+      name = "compare_to",
+      doc =
+          "Compares based on most signifigant (first) not-matching version component. "
+              + "So, for example, 1.2.3 < 1.2.4"
+  )
+  public int compareTo_skylark(SelfT other);
+}
diff --git a/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/apple/ObjcProviderApi.java b/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/apple/ObjcProviderApi.java
new file mode 100644
index 0000000000..1d44e3adee
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/apple/ObjcProviderApi.java
@@ -0,0 +1,300 @@
+// Copyright 2018 The Bazel Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//    http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.devtools.build.lib.skylarkbuildapi.apple;
+
+import com.google.devtools.build.lib.collect.nestedset.NestedSet;
+import com.google.devtools.build.lib.skylarkbuildapi.FileApi;
+import com.google.devtools.build.lib.skylarkbuildapi.StructApi;
+import com.google.devtools.build.lib.skylarkinterface.SkylarkCallable;
+import com.google.devtools.build.lib.skylarkinterface.SkylarkModule;
+import com.google.devtools.build.lib.skylarkinterface.SkylarkModuleCategory;
+import com.google.devtools.build.lib.syntax.SkylarkNestedSet;
+
+/**
+ * An interface for an info type that provides all compiling and linking information in the
+ * transitive closure of its deps that are needed for building Objective-C rules.
+ */
+@SkylarkModule(
+    name = "ObjcProvider",
+    category = SkylarkModuleCategory.PROVIDER,
+    doc = "A provider for compilation and linking of objc."
+)
+public interface ObjcProviderApi<FileApiT extends FileApi> extends StructApi {
+
+  @SkylarkCallable(name = "asset_catalog",
+      structField = true,
+      doc = "<b>Deprecated. Resource-related fields will be migrated to another provider.</b> "
+          + "Asset catalog resource files."
+  )
+  public NestedSet<FileApiT> assetCatalog();
+
+  @SkylarkCallable(name = "bundle_file",
+      structField = true,
+      doc = "<b>Deprecated. Resource-related fields will be migrated to another provider.</b> "
+          + "Files that are plopped into the final bundle at some arbitrary bundle path."
+  )
+  public SkylarkNestedSet bundleFile();
+
+  @SkylarkCallable(name = "define",
+      structField = true,
+      doc = "A set of strings from 'defines' attributes. These are to be passed as '-D' flags to "
+          + "all invocations of the compiler for this target and all depending targets."
+  )
+  public NestedSet<String> define();
+
+  @SkylarkCallable(name = "dynamic_framework_dir",
+      structField = true,
+      doc = "Exec paths of .framework directories corresponding to dynamic frameworks to link."
+  )
+  public SkylarkNestedSet dynamicFrameworkDir();
+
+  @SkylarkCallable(name = "dynamic_framework_file",
+      structField = true,
+      doc = "Files in .framework directories belonging to a dynamically linked framework."
+  )
+  public NestedSet<FileApiT> dynamicFrameworkFile();
+
+  @SkylarkCallable(name = "debug_symbols",
+      structField = true,
+      doc = "Files containing information on debug symbols."
+  )
+  public NestedSet<FileApiT> debugSymbols();
+
+  @SkylarkCallable(name = "debug_symbols_plist",
+      structField = true,
+      doc = "Files containing the plist of the debug symbols."
+  )
+  public NestedSet<FileApiT> debugSymbolsPlist();
+
+  @SkylarkCallable(name = "exported_debug_artifacts",
+      structField = true,
+      doc = "Debug files that should be exported by the top-level target."
+  )
+  public NestedSet<FileApiT> exportedDebugArtifacts();
+
+  @SkylarkCallable(name = "framework_search_path_only",
+      structField = true,
+      doc = "Exec paths of .framework directories corresponding to frameworks to include "
+          + "in search paths, but not to link."
+  )
+  public SkylarkNestedSet frameworkSearchPathOnly();
+
+  @SkylarkCallable(name = "force_load_library",
+      structField = true,
+      doc = "Libraries to load with -force_load."
+  )
+  public NestedSet<FileApiT> forceLoadLibrary();
+
+  @SkylarkCallable(name = "header",
+      structField = true,
+      doc = "All header files. These may be either public or private headers."
+  )
+  public NestedSet<FileApiT> header();
+
+  @SkylarkCallable(name = "imported_library",
+      structField = true,
+      doc = "Imported precompiled static libraries (.a files) to be linked into the binary."
+  )
+  public NestedSet<FileApiT> importedLibrary();
+
+  @SkylarkCallable(name = "include",
+      structField = true,
+      doc = "Include search paths specified with '-I' on the command line. Also known as "
+          + "header search paths (and distinct from <em>user</em> header search paths)."
+  )
+  public SkylarkNestedSet include();
+
+  @SkylarkCallable(name = "include_system",
+      structField = true,
+      doc = "System include search paths (typically specified with -isystem)."
+  )
+  public SkylarkNestedSet includeSystem();
+
+  @SkylarkCallable(name = "iquote",
+      structField = true,
+      doc = "User header search paths (typically specified with -iquote)."
+  )
+  public SkylarkNestedSet iquote();
+
+  @SkylarkCallable(name = "j2objc_library",
+      structField = true,
+      doc = "Static libraries that are built from J2ObjC-translated Java code."
+  )
+  public NestedSet<FileApiT> j2objcLibrary();
+
+  @SkylarkCallable(name = "jre_library",
+      structField = true,
+      doc = "J2ObjC JRE emulation libraries and their dependencies."
+  )
+  public NestedSet<FileApiT> jreLibrary();
+
+  @SkylarkCallable(name = "library",
+      structField = true,
+      doc = "Library (.a) files compiled by dependencies of the current target."
+  )
+  public NestedSet<FileApiT> library();
+
+  @SkylarkCallable(name = "link_inputs",
+      structField = true,
+      doc = "Link time artifacts from dependencies that do not fall into any other category such "
+          + "as libraries or archives. This catch-all provides a way to add arbitrary data (e.g. "
+          + "Swift AST files) to the linker. The rule that adds these is also responsible to "
+          + "add the necessary linker flags to 'linkopt'."
+  )
+  public NestedSet<FileApiT> linkInputs();
+
+  @SkylarkCallable(name = "linked_binary",
+      structField = true,
+      doc = "Single-architecture linked binaries to be combined for the final multi-architecture "
+          + "binary."
+  )
+  public NestedSet<FileApiT> linkedBinary();
+
+  @SkylarkCallable(name = "linkmap_file",
+      structField = true,
+      doc = "Single-architecture link map for a binary."
+  )
+  public NestedSet<FileApiT> linkmapFile();
+
+  @SkylarkCallable(name = "linkopt",
+      structField = true,
+      doc = "Linking options."
+  )
+  public NestedSet<String> linkopt();
+
+  @SkylarkCallable(name = "merge_zip",
+      structField = true,
+      doc = "<b>Deprecated. Resource-related fields will be migrated to another provider.</b> "
+          + "Merge zips to include in the bundle. The entries of these zip files are included in "
+          + "the final bundle with the same path. The entries in the merge zips should not include "
+          + "the bundle root path (e.g. 'Foo.app')."
+  )
+  public NestedSet<FileApiT> mergeZip();
+
+  @SkylarkCallable(name = "module_map",
+      structField = true,
+      doc = "Clang module maps, used to enforce proper use of private header files."
+  )
+  public NestedSet<FileApiT> moduleMap();
+
+  @SkylarkCallable(name = "multi_arch_dynamic_libraries",
+      structField = true,
+      doc = "Combined-architecture dynamic libraries to include in the final bundle."
+  )
+  public NestedSet<FileApiT> multiArchDynamicLibraries();
+
+  @SkylarkCallable(name = "multi_arch_linked_archives",
+      structField = true,
+      doc = "Combined-architecture archives to include in the final bundle."
+  )
+  public NestedSet<FileApiT> multiArchLinkedArchives();
+
+  @SkylarkCallable(name = "multi_arch_linked_binaries",
+      structField = true,
+      doc = "Combined-architecture binaries to include in the final bundle."
+  )
+  public NestedSet<FileApiT> multiArchLinkedBinaries();
+
+  @SkylarkCallable(name = "root_merge_zip",
+      structField = true,
+      doc = "<b>Deprecated. Resource-related fields will be migrated to another provider.</b> "
+          + "Merge zips to include in the ipa and outside the bundle root."
+  )
+  public NestedSet<FileApiT> rootMergeZip();
+
+  @SkylarkCallable(name = "sdk_dylib",
+      structField = true,
+      doc = "Names of SDK .dylib libraries to link with. For instance, 'libz' or 'libarchive'."
+  )
+  public NestedSet<String> sdkDylib();
+
+  @SkylarkCallable(name = "sdk_framework",
+      structField = true,
+      doc = "Names of SDK frameworks to link with (e.g. 'AddressBook', 'QuartzCore')."
+  )
+  public SkylarkNestedSet sdkFramework();
+
+  @SkylarkCallable(name = "source",
+      structField = true,
+      doc = "All transitive source files."
+  )
+  public NestedSet<FileApiT> source();
+
+  @SkylarkCallable(name = "static_framework_file",
+      structField = true,
+      doc = "Files in .framework directories that should be statically included as inputs "
+          + "when compiling and linking."
+  )
+  public NestedSet<FileApiT> staticFrameworkFile();
+
+  @SkylarkCallable(name = "storyboard",
+      structField = true,
+      doc = "<b>Deprecated. Resource-related fields will be migrated to another provider.</b> "
+          + "Files for storyboard sources."
+  )
+  public NestedSet<FileApiT> storyboard();
+
+  @SkylarkCallable(name = "strings",
+      structField = true,
+      doc = "<b>Deprecated. Resource-related fields will be migrated to another provider.</b> "
+          + "Files for strings source files."
+  )
+  public NestedSet<FileApiT> strings();
+
+  @SkylarkCallable(name = "umbrella_header",
+      structField = true,
+      doc = "Clang umbrella header. Public headers are #included in umbrella headers to be "
+          + "compatible with J2ObjC segmented headers."
+  )
+  public NestedSet<FileApiT> umbrellaHeader();
+
+  @SkylarkCallable(name = "weak_sdk_framework",
+      structField = true,
+      doc = "Names of SDK frameworks to weakly link with. For instance, 'MediaAccessibility'. "
+           + "In difference to regularly linked SDK frameworks, symbols from weakly linked "
+           + "frameworks do not cause an error if they are not present at runtime."
+  )
+  public SkylarkNestedSet weakSdkFramework();
+
+  @SkylarkCallable(name = "xcassets_dir",
+      structField = true,
+      doc = "<b>Deprecated. Resource-related fields will be migrated to another provider.</b> "
+          + "The set of all unique asset catalog directories (*.xcassets) containing files "
+          + "in 'asset_catalogs'."
+  )
+  public SkylarkNestedSet xcassetsDir();
+
+  @SkylarkCallable(name = "xcdatamodel",
+      structField = true,
+      doc = "<b>Deprecated. Resource-related fields will be migrated to another provider.</b> "
+          + "Files that comprise the data models of the final linked binary."
+  )
+  public NestedSet<FileApiT> xcdatamodel();
+
+  @SkylarkCallable(name = "xib",
+      structField = true,
+      doc = "<b>Deprecated. Resource-related fields will be migrated to another provider.</b> "
+          + ".xib resource files"
+  )
+  public NestedSet<FileApiT> xib();
+
+  @SkylarkCallable(
+      name = "framework_dir",
+      structField = true,
+      doc = "Returns all unique static framework directories (directories ending in '.framework') "
+          + "for all static framework files in this provider."
+  )
+  public SkylarkNestedSet getStaticFrameworkDirsForSkylark();
+}
diff --git a/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/apple/XcodeConfigProviderApi.java b/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/apple/XcodeConfigProviderApi.java
new file mode 100644
index 0000000000..0cc4f1e3ce
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/apple/XcodeConfigProviderApi.java
@@ -0,0 +1,48 @@
+// Copyright 2018 The Bazel Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//    http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.devtools.build.lib.skylarkbuildapi.apple;
+
+import com.google.devtools.build.lib.skylarkbuildapi.StructApi;
+import com.google.devtools.build.lib.skylarkinterface.SkylarkCallable;
+import com.google.devtools.build.lib.skylarkinterface.SkylarkModule;
+
+/**
+ * An interface for an info type containing the set of Apple versions computed from command line
+ * options and the {@code xcode_config} rule.
+ */
+@SkylarkModule(
+    name = "XcodeVersionConfig",
+    doc = "The set of Apple versions computed from command line options and the xcode_config rule.")
+public interface XcodeConfigProviderApi<ApplePlatformApiT extends ApplePlatformApi,
+    ApplePlatformTypeApiT extends ApplePlatformTypeApi> extends StructApi {
+
+  @SkylarkCallable(name = "xcode_version",
+      doc = "Returns the Xcode version that is being used to build.<p>"
+          + "This will return <code>None</code> if no Xcode versions are available.",
+      allowReturnNones = true)
+  public DottedVersionApi<?> getXcodeVersion();
+
+  @SkylarkCallable(
+      name = "minimum_os_for_platform_type",
+      doc = "The minimum compatible OS version for target simulator and devices for a particular "
+          + "platform type.")
+  public DottedVersionApi<?> getMinimumOsForPlatformType(ApplePlatformTypeApiT platformType);
+
+  @SkylarkCallable(
+      name = "sdk_version_for_platform",
+      doc = "The version of the platform SDK that will be used to build targets for the given "
+          + "platform.")
+  public DottedVersionApi<?> getSdkVersionForPlatform(ApplePlatformApiT platform);
+}
diff --git a/src/test/java/com/google/devtools/build/lib/rules/objc/BazelJ2ObjcLibraryTest.java b/src/test/java/com/google/devtools/build/lib/rules/objc/BazelJ2ObjcLibraryTest.java
index 088fdb04e3..0120bfc260 100644
--- a/src/test/java/com/google/devtools/build/lib/rules/objc/BazelJ2ObjcLibraryTest.java
+++ b/src/test/java/com/google/devtools/build/lib/rules/objc/BazelJ2ObjcLibraryTest.java
@@ -1219,7 +1219,7 @@ public class BazelJ2ObjcLibraryTest extends J2ObjcLibraryTest {
             .add("-F")
             .add(AppleToolchain.sdkDir() + "/Developer/Library/Frameworks")
             .add("-F")
-            .add(AppleToolchain.platformFrameworkDirFromConfig(appleConfiguration))
+            .add(AppleToolchain.platformDeveloperFrameworkDir(appleConfiguration))
             .add("-O0")
             .add("-DDEBUG=1")
             .add("-iquote")