diff --git a/alts/build.gradle b/alts/build.gradle
index 2b48403d91..82454bf903 100644
--- a/alts/build.gradle
+++ b/alts/build.gradle
@@ -9,8 +9,6 @@ plugins {
 
 description = "gRPC: ALTS"
 
-evaluationDependsOn(project(':grpc-core').path)
-
 dependencies {
     api project(':grpc-core')
     implementation project(':grpc-auth'),
@@ -28,7 +26,7 @@ dependencies {
     shadow project(path: ':grpc-netty-shaded', configuration: 'shadow')
 
     testImplementation project(':grpc-testing'),
-            project(':grpc-core').sourceSets.test.output,
+            testFixtures(project(':grpc-core')),
             project(':grpc-testing-proto'),
             libraries.guava,
             libraries.junit,
diff --git a/api/build.gradle b/api/build.gradle
index 05cd80674c..e106cad6a4 100644
--- a/api/build.gradle
+++ b/api/build.gradle
@@ -1,5 +1,6 @@
 plugins {
     id "java-library"
+    id "java-test-fixtures"
     id "maven-publish"
 
     id "me.champeau.jmh"
@@ -8,15 +9,16 @@ plugins {
 
 description = 'gRPC: API'
 
-evaluationDependsOn(project(':grpc-context').path)
-
 dependencies {
     api project(':grpc-context'),
             libraries.jsr305,
             libraries.errorprone.annotations
     implementation libraries.guava
 
-    testImplementation project(':grpc-context').sourceSets.test.output,
+    testFixturesImplementation libraries.guava,
+            libraries.junit,
+            libraries.mockito.core
+    testImplementation testFixtures(project(':grpc-context')),
             project(':grpc-testing'),
             project(':grpc-grpclb')
     testImplementation (libraries.guava.testlib) {
@@ -32,3 +34,6 @@ tasks.named("javadoc").configure {
     // We want io.grpc.Internal, but not io.grpc.Internal*
     exclude 'io/grpc/Internal?*.java'
 }
+
+components.java.withVariantsFromConfiguration(configurations.testFixturesApiElements) { skip() }
+components.java.withVariantsFromConfiguration(configurations.testFixturesRuntimeElements) { skip() }
diff --git a/api/src/test/java/io/grpc/ForwardingTestUtil.java b/api/src/testFixtures/java/io/grpc/ForwardingTestUtil.java
similarity index 100%
rename from api/src/test/java/io/grpc/ForwardingTestUtil.java
rename to api/src/testFixtures/java/io/grpc/ForwardingTestUtil.java
diff --git a/api/src/test/java/io/grpc/IntegerMarshaller.java b/api/src/testFixtures/java/io/grpc/IntegerMarshaller.java
similarity index 100%
rename from api/src/test/java/io/grpc/IntegerMarshaller.java
rename to api/src/testFixtures/java/io/grpc/IntegerMarshaller.java
diff --git a/api/src/test/java/io/grpc/ManagedChannelRegistryAccessor.java b/api/src/testFixtures/java/io/grpc/ManagedChannelRegistryAccessor.java
similarity index 100%
rename from api/src/test/java/io/grpc/ManagedChannelRegistryAccessor.java
rename to api/src/testFixtures/java/io/grpc/ManagedChannelRegistryAccessor.java
diff --git a/api/src/test/java/io/grpc/StringMarshaller.java b/api/src/testFixtures/java/io/grpc/StringMarshaller.java
similarity index 100%
rename from api/src/test/java/io/grpc/StringMarshaller.java
rename to api/src/testFixtures/java/io/grpc/StringMarshaller.java
diff --git a/authz/build.gradle b/authz/build.gradle
index 2e6cfc11ec..1eb6c212d0 100644
--- a/authz/build.gradle
+++ b/authz/build.gradle
@@ -19,7 +19,7 @@ dependencies {
 
     testImplementation project(':grpc-testing'),
             project(':grpc-testing-proto'),
-            project(':grpc-core').sourceSets.test.output  // for FakeClock
+            testFixtures(project(':grpc-core'))
     testImplementation (libraries.guava.testlib) {
         exclude group: 'junit', module: 'junit'
     }
diff --git a/binder/build.gradle b/binder/build.gradle
index 1ba46d9334..3751a67733 100644
--- a/binder/build.gradle
+++ b/binder/build.gradle
@@ -7,22 +7,6 @@ description = 'gRPC BinderChannel'
 
 android {
     namespace 'io.grpc.binder'
-    sourceSets {
-        test {
-            java {
-                srcDirs += "${projectDir}/../core/src/test/java/"
-                setIncludes(["io/grpc/internal/FakeClock.java",
-                             "io/grpc/binder/**"])
-            }
-        }
-        androidTest {
-            java {
-                srcDirs += "${projectDir}/../core/src/test/java/"
-                setIncludes(["io/grpc/internal/AbstractTransportTest.java",
-                             "io/grpc/binder/**"])
-            }
-        }
-    }
     compileSdkVersion 31
     compileOptions {
         sourceCompatibility 1.8
@@ -72,6 +56,7 @@ dependencies {
     }
     testImplementation libraries.truth
     testImplementation project(':grpc-testing')
+    testImplementation testFixtures(project(':grpc-core'))
 
     androidTestAnnotationProcessor libraries.auto.value
     androidTestImplementation project(':grpc-testing')
@@ -88,6 +73,7 @@ dependencies {
     androidTestImplementation (libraries.guava.testlib) {
         exclude group: 'junit', module: 'junit'
     }
+    androidTestImplementation testFixtures(project(':grpc-core'))
 }
 
 import net.ltgt.gradle.errorprone.CheckSeverity
diff --git a/census/build.gradle b/census/build.gradle
index 02b7e6395b..25948f17f6 100644
--- a/census/build.gradle
+++ b/census/build.gradle
@@ -7,17 +7,15 @@ plugins {
 
 description = 'gRPC: Census'
 
-evaluationDependsOn(project(':grpc-api').path)
-
 dependencies {
     api project(':grpc-api')
     implementation libraries.guava,
             libraries.opencensus.api,
             libraries.opencensus.contrib.grpc.metrics
 
-    testImplementation project(':grpc-api').sourceSets.test.output,
-            project(':grpc-context').sourceSets.test.output,
-            project(':grpc-core').sourceSets.test.output,
+    testImplementation testFixtures(project(':grpc-api')),
+            testFixtures(project(':grpc-context')),
+            testFixtures(project(':grpc-core')),
             project(':grpc-testing'),
             libraries.opencensus.impl
 
diff --git a/context/build.gradle b/context/build.gradle
index 5815374aeb..8e02271bff 100644
--- a/context/build.gradle
+++ b/context/build.gradle
@@ -1,5 +1,6 @@
 plugins {
     id "java"
+    id "java-test-fixtures"
     id "maven-publish"
 
     id "me.champeau.gradle.japicmp"
@@ -13,6 +14,10 @@ sourceCompatibility = 1.7
 targetCompatibility = 1.7
 
 dependencies {
+    testFixturesApi libraries.truth
+    // Explicitly choose the guava version to stay Java 7-compatible.
+    testFixturesImplementation 'com.google.guava:guava:30.1.1-android'
+    testFixturesImplementation libraries.jsr305
     testImplementation libraries.jsr305
     // Explicitly choose the guava version to stay Java 7-compatible. The rest of gRPC can move
     // forward to Java 8-requiring versions. This is also only used for testing, so is unlikely to
@@ -23,3 +28,6 @@ dependencies {
     signature "org.codehaus.mojo.signature:java17:1.0@signature"
     signature "net.sf.androidscents.signature:android-api-level-14:4.0_r4@signature"
 }
+
+components.java.withVariantsFromConfiguration(configurations.testFixturesApiElements) { skip() }
+components.java.withVariantsFromConfiguration(configurations.testFixturesRuntimeElements) { skip() }
diff --git a/context/src/test/java/io/grpc/StaticTestingClassLoader.java b/context/src/testFixtures/java/io/grpc/StaticTestingClassLoader.java
similarity index 100%
rename from context/src/test/java/io/grpc/StaticTestingClassLoader.java
rename to context/src/testFixtures/java/io/grpc/StaticTestingClassLoader.java
diff --git a/context/src/test/java/io/grpc/testing/DeadlineSubject.java b/context/src/testFixtures/java/io/grpc/testing/DeadlineSubject.java
similarity index 100%
rename from context/src/test/java/io/grpc/testing/DeadlineSubject.java
rename to context/src/testFixtures/java/io/grpc/testing/DeadlineSubject.java
diff --git a/core/build.gradle b/core/build.gradle
index 3e34037136..f97c80b753 100644
--- a/core/build.gradle
+++ b/core/build.gradle
@@ -6,6 +6,7 @@ buildscript {
 
 plugins {
     id "java-library"
+    id "java-test-fixtures"
     id "maven-publish"
 
     id "me.champeau.gradle.japicmp"
@@ -19,9 +20,6 @@ import com.google.common.primitives.Bytes;
 
 description = 'gRPC: Core'
 
-evaluationDependsOn(project(':grpc-context').path)
-evaluationDependsOn(project(':grpc-api').path)
-
 dependencies {
     api project(':grpc-api')
     implementation libraries.gson,
@@ -30,8 +28,13 @@ dependencies {
             libraries.errorprone.annotations,
             libraries.guava,
             libraries.perfmark.api
-    testImplementation project(':grpc-context').sourceSets.test.output,
-            project(':grpc-api').sourceSets.test.output,
+    testFixturesApi libraries.junit
+    testFixturesImplementation libraries.guava,
+            libraries.mockito.core,
+            libraries.truth,
+            project(':grpc-testing')
+    testImplementation testFixtures(project(':grpc-context')),
+            testFixtures(project(':grpc-api')),
             project(':grpc-testing'),
             project(':grpc-grpclb')
     testImplementation (libraries.guava.testlib) {
@@ -61,6 +64,9 @@ animalsniffer {
     ]
 }
 
+components.java.withVariantsFromConfiguration(configurations.testFixturesApiElements) { skip() }
+components.java.withVariantsFromConfiguration(configurations.testFixturesRuntimeElements) { skip() }
+
 import net.ltgt.gradle.errorprone.CheckSeverity
 
 def replaceBytes(byte[] haystack, byte[] needle, byte[] replacement) {
diff --git a/core/src/test/java/io/grpc/internal/AbstractTransportTest.java b/core/src/testFixtures/java/io/grpc/internal/AbstractTransportTest.java
similarity index 100%
rename from core/src/test/java/io/grpc/internal/AbstractTransportTest.java
rename to core/src/testFixtures/java/io/grpc/internal/AbstractTransportTest.java
diff --git a/core/src/test/java/io/grpc/internal/FakeClock.java b/core/src/testFixtures/java/io/grpc/internal/FakeClock.java
similarity index 100%
rename from core/src/test/java/io/grpc/internal/FakeClock.java
rename to core/src/testFixtures/java/io/grpc/internal/FakeClock.java
diff --git a/core/src/test/java/io/grpc/internal/NoopClientStreamListener.java b/core/src/testFixtures/java/io/grpc/internal/NoopClientStreamListener.java
similarity index 100%
rename from core/src/test/java/io/grpc/internal/NoopClientStreamListener.java
rename to core/src/testFixtures/java/io/grpc/internal/NoopClientStreamListener.java
diff --git a/core/src/test/java/io/grpc/internal/ReadableBufferTestBase.java b/core/src/testFixtures/java/io/grpc/internal/ReadableBufferTestBase.java
similarity index 100%
rename from core/src/test/java/io/grpc/internal/ReadableBufferTestBase.java
rename to core/src/testFixtures/java/io/grpc/internal/ReadableBufferTestBase.java
diff --git a/core/src/test/java/io/grpc/internal/TestUtils.java b/core/src/testFixtures/java/io/grpc/internal/TestUtils.java
similarity index 100%
rename from core/src/test/java/io/grpc/internal/TestUtils.java
rename to core/src/testFixtures/java/io/grpc/internal/TestUtils.java
diff --git a/core/src/test/java/io/grpc/internal/WritableBufferAllocatorTestBase.java b/core/src/testFixtures/java/io/grpc/internal/WritableBufferAllocatorTestBase.java
similarity index 100%
rename from core/src/test/java/io/grpc/internal/WritableBufferAllocatorTestBase.java
rename to core/src/testFixtures/java/io/grpc/internal/WritableBufferAllocatorTestBase.java
diff --git a/core/src/test/java/io/grpc/internal/WritableBufferTestBase.java b/core/src/testFixtures/java/io/grpc/internal/WritableBufferTestBase.java
similarity index 100%
rename from core/src/test/java/io/grpc/internal/WritableBufferTestBase.java
rename to core/src/testFixtures/java/io/grpc/internal/WritableBufferTestBase.java
diff --git a/gcp-observability/build.gradle b/gcp-observability/build.gradle
index 265c0d682f..48312d7fbc 100644
--- a/gcp-observability/build.gradle
+++ b/gcp-observability/build.gradle
@@ -62,7 +62,7 @@ dependencies {
             ('io.opencensus:opencensus-api:0.31.1'),
             ('com.google.guava:guava:31.1-jre')
 
-    testImplementation project(':grpc-context').sourceSets.test.output,
+    testImplementation testFixtures(project(':grpc-context')),
             project(':grpc-testing'),
             project(':grpc-testing-proto')
     testImplementation (libraries.guava.testlib) {
diff --git a/googleapis/build.gradle b/googleapis/build.gradle
index 540011986c..72f5b97940 100644
--- a/googleapis/build.gradle
+++ b/googleapis/build.gradle
@@ -13,7 +13,7 @@ dependencies {
                    project(':grpc-core'),
                    project(path: ':grpc-xds', configuration: 'shadow'),
                    libraries.guava.jre // JRE required by transitive protobuf-java-util
-    testImplementation project(':grpc-core').sourceSets.test.output
+    testImplementation testFixtures(project(':grpc-core'))
 
     signature libraries.signature.java
 }
diff --git a/grpclb/build.gradle b/grpclb/build.gradle
index 6fd64c8429..7aa2d62b0f 100644
--- a/grpclb/build.gradle
+++ b/grpclb/build.gradle
@@ -9,8 +9,6 @@ plugins {
 
 description = "gRPC: GRPCLB LoadBalancer plugin"
 
-evaluationDependsOn(project(':grpc-core').path)
-
 dependencies {
     implementation project(':grpc-core'),
             project(':grpc-protobuf'),
@@ -21,7 +19,7 @@ dependencies {
     runtimeOnly libraries.errorprone.annotations
     compileOnly libraries.javax.annotation
     testImplementation libraries.truth,
-            project(':grpc-core').sourceSets.test.output
+            testFixtures(project(':grpc-core'))
 
     signature libraries.signature.java
 }
diff --git a/interop-testing/build.gradle b/interop-testing/build.gradle
index ad032d7399..96d4ca3614 100644
--- a/interop-testing/build.gradle
+++ b/interop-testing/build.gradle
@@ -13,10 +13,6 @@ configurations {
     alpnagent
 }
 
-evaluationDependsOn(project(':grpc-core').path)
-evaluationDependsOn(project(':grpc-context').path)
-evaluationDependsOn(project(':grpc-api').path)
-
 dependencies {
     implementation project(path: ':grpc-alts', configuration: 'shadow'),
             project(':grpc-auth'),
@@ -49,9 +45,9 @@ dependencies {
             libraries.netty.tcnative.classes,
             project(':grpc-grpclb'),
             project(':grpc-rls')
-    testImplementation project(':grpc-context').sourceSets.test.output,
-            project(':grpc-api').sourceSets.test.output,
-            project(':grpc-core').sourceSets.test.output,
+    testImplementation testFixtures(project(':grpc-context')),
+            testFixtures(project(':grpc-api')),
+            testFixtures(project(':grpc-core')),
             libraries.mockito.core,
             libraries.okhttp
     alpnagent libraries.jetty.alpn.agent
diff --git a/istio-interop-testing/build.gradle b/istio-interop-testing/build.gradle
index 7ba342c688..b4495002af 100644
--- a/istio-interop-testing/build.gradle
+++ b/istio-interop-testing/build.gradle
@@ -13,8 +13,6 @@ configurations {
     alpnagent
 }
 
-evaluationDependsOn(project(':grpc-context').path)
-
 dependencies {
     implementation  project(':grpc-core'),
             project(':grpc-netty'),
@@ -28,9 +26,9 @@ dependencies {
 
     runtimeOnly libraries.netty.tcnative,
             libraries.netty.tcnative.classes
-    testImplementation project(':grpc-context').sourceSets.test.output,
-            project(':grpc-api').sourceSets.test.output,
-            project(':grpc-core').sourceSets.test.output,
+    testImplementation testFixtures(project(':grpc-context')),
+            testFixtures(project(':grpc-api')),
+            testFixtures(project(':grpc-core')),
             libraries.mockito.core,
             libraries.junit,
             libraries.truth
diff --git a/netty/build.gradle b/netty/build.gradle
index 16d3279528..0f22d27746 100644
--- a/netty/build.gradle
+++ b/netty/build.gradle
@@ -13,8 +13,6 @@ configurations {
     alpnagent
 }
 
-evaluationDependsOn(project(':grpc-core').path)
-
 dependencies {
     api project(':grpc-core'),
             libraries.netty.codec.http2
@@ -25,8 +23,8 @@ dependencies {
             libraries.netty.unix.common
 
     // Tests depend on base class defined by core module.
-    testImplementation project(':grpc-core').sourceSets.test.output,
-            project(':grpc-api').sourceSets.test.output,
+    testImplementation testFixtures(project(':grpc-core')),
+            testFixtures(project(':grpc-api')),
             project(':grpc-testing'),
             project(':grpc-testing-proto'),
             libraries.conscrypt,
diff --git a/okhttp/build.gradle b/okhttp/build.gradle
index 439abaa337..37d033350c 100644
--- a/okhttp/build.gradle
+++ b/okhttp/build.gradle
@@ -8,8 +8,6 @@ plugins {
 
 description = "gRPC: OkHttp"
 
-evaluationDependsOn(project(':grpc-core').path)
-
 dependencies {
     api project(':grpc-core')
     implementation libraries.okio,
@@ -18,8 +16,8 @@ dependencies {
     // Make okhttp dependencies compile only
     compileOnly libraries.okhttp
     // Tests depend on base class defined by core module.
-    testImplementation project(':grpc-core').sourceSets.test.output,
-            project(':grpc-api').sourceSets.test.output,
+    testImplementation testFixtures(project(':grpc-core')),
+            testFixtures(project(':grpc-api')),
             project(':grpc-testing'),
             project(':grpc-testing-proto'),
             libraries.netty.codec.http2,
diff --git a/rls/build.gradle b/rls/build.gradle
index ddd8cb6587..453052addf 100644
--- a/rls/build.gradle
+++ b/rls/build.gradle
@@ -8,8 +8,6 @@ plugins {
 
 description = "gRPC: RouteLookupService Loadbalancing plugin"
 
-evaluationDependsOn(project(':grpc-core').path)
-
 dependencies {
     implementation project(':grpc-core'),
             project(':grpc-protobuf'),
@@ -22,7 +20,7 @@ dependencies {
             project(':grpc-grpclb'),
             project(':grpc-testing'),
             project(':grpc-testing-proto'),
-            project(':grpc-core').sourceSets.test.output  // for FakeClock
+            testFixtures(project(':grpc-core'))
     signature libraries.signature.java
 }
 
diff --git a/services/build.gradle b/services/build.gradle
index 4b445c2d1e..76a767dce8 100644
--- a/services/build.gradle
+++ b/services/build.gradle
@@ -16,8 +16,6 @@ tasks.named("compileJava").configure {
     ]
 }
 
-evaluationDependsOn(project(':grpc-core').path)
-
 dependencies {
     api project(':grpc-protobuf'),
             project(':grpc-stub'),
@@ -30,7 +28,7 @@ dependencies {
     compileOnly libraries.javax.annotation
     testImplementation project(':grpc-testing'),
             libraries.netty.transport.epoll, // for DomainSocketAddress
-            project(':grpc-core').sourceSets.test.output  // for FakeClock
+            testFixtures(project(':grpc-core'))
     testCompileOnly libraries.javax.annotation
     signature libraries.signature.java
 }
diff --git a/testing/build.gradle b/testing/build.gradle
index 35da61f11f..512388cd07 100644
--- a/testing/build.gradle
+++ b/testing/build.gradle
@@ -8,8 +8,6 @@ plugins {
 
 description = "gRPC: Testing"
 
-evaluationDependsOn(project(':grpc-core').path)
-
 dependencies {
     api project(':grpc-core'),
             project(':grpc-stub'),
@@ -24,7 +22,7 @@ dependencies {
     }
 
     testImplementation project(':grpc-testing-proto'),
-            project(':grpc-core').sourceSets.test.output
+            testFixtures(project(':grpc-core'))
 
     signature libraries.signature.java
     signature libraries.signature.android
diff --git a/xds/build.gradle b/xds/build.gradle
index a33fa6e6d5..ade629f380 100644
--- a/xds/build.gradle
+++ b/xds/build.gradle
@@ -11,8 +11,6 @@ plugins {
 
 description = "gRPC: XDS plugin"
 
-evaluationDependsOn(project(':grpc-core').path)
-
 sourceSets {
     thirdparty {
         java {
@@ -57,7 +55,7 @@ dependencies {
     def nettyDependency = implementation project(':grpc-netty')
 
     testImplementation project(':grpc-rls')
-    testImplementation project(':grpc-core').sourceSets.test.output
+    testImplementation testFixtures(project(':grpc-core'))
 
     annotationProcessor libraries.auto.value
     // At runtime use the epoll included in grpc-netty-shaded