diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index c4af76a0e..9e1d75c5a 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -13,9 +13,14 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v2
+      # Install Java 8 for cross-compilation support. Setting it up before
+      # Java 11 means it comes later in $PATH (because of how setup-java works)
       - uses: actions/setup-java@v1
         with:
           java-version: 8
+      - uses: actions/setup-java@v1
+        with:
+          java-version: 11
       - uses: actions/cache@v1
         with:
           path: ~/.gradle
@@ -27,4 +32,4 @@ jobs:
           BINTRAY_USER: ${{ secrets.BINTRAY_USER }}
           BINTRAY_API_KEY: ${{ secrets.BINTRAY_API_KEY }}
           GRADLE_OPTS: -Xmx6g -Xms6g -Dorg.gradle.daemon=false
-        run: ./gradlew -PenablePublishing=true -PbintrayUser="${BINTRAY_USER}" -PbintrayKey="${BINTRAY_API_KEY}" build snapshot --stacktrace
+        run: ./gradlew -PenableCrossCompilerPlugin=true -PenablePublishing=true -PbintrayUser="${BINTRAY_USER}" -PbintrayKey="${BINTRAY_API_KEY}" build snapshot --stacktrace
diff --git a/.github/workflows/pr.yml b/.github/workflows/pr.yml
index 344085601..7254e2fec 100644
--- a/.github/workflows/pr.yml
+++ b/.github/workflows/pr.yml
@@ -7,9 +7,14 @@ jobs:
     runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@v2
+    # Install Java 8 for cross-compilation support. Setting it up before
+    # Java 11 means it comes later in $PATH (because of how setup-java works)
     - uses: actions/setup-java@v1
       with:
         java-version: 8
+    - uses: actions/setup-java@v1
+      with:
+        java-version: 11
     - uses: actions/cache@v1
       with:
         path: ~/.gradle
@@ -19,4 +24,4 @@ jobs:
     - name: Build
       env:
         GRADLE_OPTS: -Xmx6g -Xms6g -Dorg.gradle.daemon=false
-      run: ./gradlew build
+      run: ./gradlew -PenableCrossCompilerPlugin=true build
diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index 19125dba8..18d87d1e5 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -12,9 +12,14 @@ jobs:
     steps:
       - uses: actions/checkout@v2
       - run: git fetch --prune --unshallow
+      # Install Java 8 for cross-compilation support. Setting it up before
+      # Java 11 means it comes later in $PATH (because of how setup-java works)
       - uses: actions/setup-java@v1
         with:
           java-version: 8
+      - uses: actions/setup-java@v1
+        with:
+          java-version: 11
       - uses: actions/cache@v1
         with:
           path: ~/.gradle
@@ -37,7 +42,7 @@ jobs:
           BINTRAY_API_KEY: ${{ secrets.BINTRAY_API_KEY }}
           GRADLE_OPTS: -Xmx6g -Xms6g -Dorg.gradle.daemon=false
         run: |
-          ./gradlew -PenablePublishing=true --info -Prelease.disableGitChecks=true -Prelease.useLastTag=true -PbintrayUser="${BINTRAY_USER}" -PbintrayKey="${BINTRAY_API_KEY}" candidate
+          ./gradlew -PenableCrossCompilerPlugin=true -PenablePublishing=true --info -Prelease.disableGitChecks=true -Prelease.useLastTag=true -PbintrayUser="${BINTRAY_USER}" -PbintrayKey="${BINTRAY_API_KEY}" candidate
       - name: Release build
         if: steps.release_info.outputs.IS_CANDIDATE == 'false'
         env:
@@ -45,7 +50,7 @@ jobs:
           BINTRAY_API_KEY: ${{ secrets.BINTRAY_API_KEY }}
           GRADLE_OPTS: -Xmx6g -Xms6g -Dorg.gradle.daemon=false
         run: |
-          ./gradlew -PenablePublishing=true --info -Prelease.disableGitChecks=true -Prelease.useLastTag=true -PbintrayUser="${BINTRAY_USER}" -PbintrayKey="${BINTRAY_API_KEY}" final
+          ./gradlew -PenableCrossCompilerPlugin=true -PenablePublishing=true --info -Prelease.disableGitChecks=true -Prelease.useLastTag=true -PbintrayUser="${BINTRAY_USER}" -PbintrayKey="${BINTRAY_API_KEY}" final
       - name: Create release
         if: steps.release_info.outputs.SKIP_RELEASE == 'false'
         uses: actions/create-release@v1
diff --git a/Dockerfile.compile b/Dockerfile.compile
index c8a7af415..df57033e3 100644
--- a/Dockerfile.compile
+++ b/Dockerfile.compile
@@ -1,5 +1,11 @@
-FROM openjdk:8
+FROM ubuntu:bionic
+RUN apt-get update && apt-get install -y \
+    openjdk-8-jdk \
+    openjdk-11-jdk \
+ && rm -rf /var/lib/apt/lists/*
 MAINTAINER sig-platform@spinnaker.io
+ENV JAVA_HOME /usr/lib/jvm/java-11-openjdk-amd64
+ENV JDK_18 /usr/lib/jvm/java-8-openjdk-amd64
 ENV GRADLE_USER_HOME /workspace/.gradle
-ENV GRADLE_OPTS -Xmx2048m
-CMD ./gradlew --no-daemon fiat-web:installDist -x test
+ENV GRADLE_OPTS -Xmx4g
+CMD ./gradlew --no-daemon -PenableCrossCompilerPlugin=true fiat-web:installDist -x test
diff --git a/fiat-roles/src/main/java/com/netflix/spinnaker/fiat/roles/UserRolesSyncer.java b/fiat-roles/src/main/java/com/netflix/spinnaker/fiat/roles/UserRolesSyncer.java
index 930f68a12..17d8c56db 100644
--- a/fiat-roles/src/main/java/com/netflix/spinnaker/fiat/roles/UserRolesSyncer.java
+++ b/fiat-roles/src/main/java/com/netflix/spinnaker/fiat/roles/UserRolesSyncer.java
@@ -36,6 +36,7 @@
 import com.netflix.spinnaker.kork.lock.LockManager;
 import java.time.Duration;
 import java.util.ArrayList;
+import java.util.Collection;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
@@ -273,10 +274,11 @@ public long updateUserPermissions(Map<String, UserPermission> permissionsById) {
     long count =
         timeIt(
             "syncUsers",
-            () ->
-                permissionsResolver.resolve(extUsers).values().stream()
-                    .map(permission -> permissionsRepository.put(permission))
-                    .count());
+            () -> {
+              Collection<UserPermission> values = permissionsResolver.resolve(extUsers).values();
+              values.forEach(permissionsRepository::put);
+              return values.size();
+            });
     log.info("Synced {} non-anonymous user roles.", count);
     return count;
   }
diff --git a/gradle.properties b/gradle.properties
index 2101cb8bd..f54626e80 100644
--- a/gradle.properties
+++ b/gradle.properties
@@ -1,6 +1,6 @@
 #Tue Mar 31 21:48:04 UTC 2020
 enablePublishing=false
-spinnakerGradleVersion=7.7.0
+spinnakerGradleVersion=7.9.0
 korkVersion=7.31.1
 org.gradle.parallel=true
 includeProviders=file,github,google-groups,ldap