diff --git a/.github/actions/setup-build-and-test-w-make-impl/action.yml b/.github/actions/setup-build-and-test-w-make-impl/action.yml
index 34d7e37ef8..c4904a93ee 100644
--- a/.github/actions/setup-build-and-test-w-make-impl/action.yml
+++ b/.github/actions/setup-build-and-test-w-make-impl/action.yml
@@ -55,7 +55,7 @@ runs:
     shell: bash
   - name: Configure
     run: |-
-      ../repo/configure --enable-protobuf --with-android-sdk="$(pwd)/../sdk" ${{ inputs.configure_extra }}
+      ../repo/configure --enable-protobuf --with-android-sdk="$(pwd)/../sdk" --with-r8="$(pwd)/../r8.jar" ${{ inputs.configure_extra }}
     working-directory: build
     shell: bash
   - name: Build
diff --git a/.github/actions/test-build-setup/action.yml b/.github/actions/test-build-setup/action.yml
index b2aba46d7c..e25b850e96 100644
--- a/.github/actions/test-build-setup/action.yml
+++ b/.github/actions/test-build-setup/action.yml
@@ -18,12 +18,12 @@ runs:
       path: sdk.tar.zstd
   - name: Check/Install (SDK)
     run: |-
-      if [ -e sdk/build-tools/29.0.2/dx ] ; then echo "Found SDK." ; exit 0 ; fi
+      if [ -e sdk/build-tools/29.0.2/aapt2 ] ; then echo "Found SDK." ; exit 0 ; fi
 
-      # Check whether cache file exists, then check dx again.
+      # Check whether cache file exists, then check aapt2 again.
       if [ -f "sdk.tar.zstd" ] ; then
         zstd --decompress --stdout sdk.tar.zstd | tar xf -
-        if [ -e sdk/build-tools/29.0.2/dx ] ; then echo "Unpacked SDK." ; exit 0 ; fi
+        if [ -e sdk/build-tools/29.0.2/aapt2 ] ; then echo "Unpacked SDK." ; exit 0 ; fi
       fi
 
       # Download.
@@ -42,3 +42,19 @@ runs:
       rm -rf sdk/emulator 2>/dev/null
       tar cf - sdk | zstd -T0 -9 > sdk.tar.zstd
     shell: bash
+  # d8 is pinned to an R8 release instead of taken from the SDK: the build-tools
+  # d8 tracks the SDK release train rather than the Android Gradle Plugin, and
+  # lags it by years. Keep this version aligned with the AGP release Redex is
+  # expected to consume the output of.
+  - name: Cache R8
+    uses: actions/cache@v5
+    with:
+      key: v1-r8-8.8.34
+      path: r8.jar
+  - name: Check/Install (R8)
+    run: |-
+      if [ -f r8.jar ] ; then echo "Found R8." ; exit 0 ; fi
+
+      echo "R8 missing, downloading..."
+      wget -O r8.jar https://maven.google.com/com/android/tools/r8/8.8.34/r8-8.8.34.jar
+    shell: bash
diff --git a/configure.ac b/configure.ac
index ebe093436b..f6a17b36c3 100644
--- a/configure.ac
+++ b/configure.ac
@@ -123,21 +123,30 @@ AC_ARG_WITH([android-sdk],
         [AC_PATH_PROG([PROTOC], [protoc], [no])])
     ]
 )
-# Look for dx & android.jar.
+# The R8 jar is pinned rather than taken from the SDK: the d8 bundled with the
+# Android build-tools tracks the SDK release train, not the Android Gradle
+# Plugin, and its dex output is years behind the d8 that ships in AGP.
+AC_ARG_WITH([r8],
+    [AS_HELP_STRING([--with-r8=/path/to/r8.jar],
+        [Location of the R8 jar, which provides d8, for testing.])],
+    [R8_JAR="$withval"],
+    []
+)
+# Look for java, the R8 jar & android.jar.
 AS_IF([test "x$NO_ANDROID_HOME" = "xno"],
     [],
     [
-        # Do not assume a totally new SDK. Try platform 29.
-        AC_PATH_PROG(
-            DX,
-            dx,
-            no,
-            "$ANDROID_HOME/build-tools/29.0.2:$PATH"
-        )
-        AS_IF([test "x$DX" = "xno"],
-            [AC_MSG_ERROR([--with-android-sdk option was specified but does not seem to point at a valid Android SDK installation])]
+        AC_PATH_PROG([JAVA], [java], [no])
+        AS_IF([test "x$JAVA" = "xno"],
+            [AC_MSG_ERROR([java is required to run d8])]
             []
         )
+        AC_CHECK_FILE(
+            "$R8_JAR",
+            [AC_SUBST(R8_JAR,"$R8_JAR")],
+            [AC_MSG_ERROR([--with-r8 must point at an R8 jar providing com.android.tools.r8.D8])]
+        )
+        # Do not assume a totally new SDK. Try platform 29.
         AC_CHECK_FILE(
             "$ANDROID_HOME/platforms/android-29/android.jar",
             [
diff --git a/test/integ/Makefile.am b/test/integ/Makefile.am
index 8bbf4d7e4f..ac1c16ad6f 100644
--- a/test/integ/Makefile.am
+++ b/test/integ/Makefile.am
@@ -1,10 +1,12 @@
 include $(top_srcdir)/Makefile.inc
 include $(top_srcdir)/test/Makefile.inc
 
-DX = @DX@
+JAVA = @JAVA@
+R8_JAR = @R8_JAR@
 
 ANDROID_SDK = @ANDROID_SDK@
 ANDROID_PLATFORM_VERSION = @ANDROID_PLATFORM_VERSION@
+ANDROID_JAR = $(ANDROID_SDK)/platforms/$(ANDROID_PLATFORM_VERSION)/android.jar
 
 AM_CXXFLAGS = --std=gnu++20
 AM_CPPFLAGS = $(COMMON_INCLUDES) $(COMMON_TEST_INCLUDES)
@@ -215,8 +217,10 @@ EXTRA_uses_app_module_annotation_test_DEPENDENCIES = uses_app_module_annotation-
 verifier_artifacts_test_SOURCES = VerifierTest.cpp
 EXTRA_verifier_artifacts_test_DEPENDENCIES = verifier_artifacts_test-class.dex
 
-# Note: Should switch to d8, instead.
-javac_source_target = -source 8 -target 8
+javac_source_target = -source 11 -target 11
+
+# Matches the platform the tests are compiled and run against.
+d8_min_api = 29
 
 define create_jar
 	mkdir -p $@.tmp
@@ -226,8 +230,13 @@ endef
 
 SUFFIXES = .dex
 
+# d8 only writes into a directory or a zip, always naming the result
+# classes.dex, so the single-dex output has to be moved into place.
 .jar.dex:
-	$(DX) --dex --output=$@ $^
+	mkdir -p $@.tmp
+	$(JAVA) -cp $(R8_JAR) com.android.tools.r8.D8 --min-api $(d8_min_api) \
+		--lib $(ANDROID_JAR) --output $@.tmp $^
+	mv $@.tmp/classes.dex $@
 
 app_module_usage_test-class.jar: AppModuleUsageClass.java
 	$(create_jar)