diff --git a/.circleci/config.yml b/.circleci/config.yml
index 75ce7aa..965b273 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -1,83 +1,33 @@
 ---
+# Prometheus has switched to GitHub action.
+# Circle CI is not disabled repository-wise so that previous pull requests
+# continue working.
+# This file does not generate any CircleCI workflow.
+
 version: 2.1
 
 executors:
-  # Whenever the Go version is updated here, .promu.yml should also be updated.
   golang:
     docker:
-    - image: cimg/go:1.25
+      - image: busybox
 
 jobs:
-  test:
-    executor: golang
-
-    steps:
-    - setup_remote_docker
-    - checkout
-    - run: go build -o promu-intermediate
-    - run: make check_license style unused lint test build PROMU=./promu-intermediate
-    - store_artifacts:
-        path: promu
-        destination: /build/promu
-    - run: rm -v promu promu-intermediate
-    - run: git diff --exit-code
-
-  build:
-    executor: golang
-    environment:
-        PROMU: ./promu-intermediate
-    working_directory: /home/circleci/.go_workspace/src/github.com/prometheus/promu
-    parallelism: 5
-
-    steps:
-    - setup_remote_docker
-    - checkout
-    - run: go build -o promu-intermediate
-    - run: ./promu-intermediate crossbuild -v --parallelism $CIRCLE_NODE_TOTAL --parallelism-thread $CIRCLE_NODE_INDEX
-    - persist_to_workspace:
-        root: .
-        paths:
-        - .build
-    - store_artifacts:
-        path: .build
-        destination: /build
-
-  release_tags:
+  noopjob:
     executor: golang
-    environment:
-        PROMU: ./promu-intermediate
 
     steps:
-    - checkout
-    - attach_workspace:
-        at: .
-    - run: go build -o promu-intermediate
-    - run: ./promu-intermediate crossbuild tarballs
-    - run: ./promu-intermediate checksum .tarballs
-    - run: ./promu-intermediate release .tarballs
-    - store_artifacts:
-        path: .tarballs
-        destination: releases
+      - run:
+          command: "true"
 
 workflows:
   version: 2
-  promu:
+  prometheus:
     jobs:
-    - test:
-        filters:
-          tags:
-            only: /.*/
-    - build:
-        filters:
-          tags:
-            only: /.*/
-    - release_tags:
-        context: org-context
-        requires:
-        - test
-        - build
-        filters:
-          tags:
-            only: /^v[0-9]+(\.[0-9]+){2}(-.+|[^-.]*)$/
-          branches:
-            ignore: /.*/
+      - noopjob
+    triggers:
+      - schedule:
+          cron: "0 0 30 2 *"
+          filters:
+            branches:
+              only:
+                - main
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
new file mode 100644
index 0000000..deb4d38
--- /dev/null
+++ b/.github/workflows/ci.yml
@@ -0,0 +1,93 @@
+name: CI
+
+on:
+  push:
+    tags:
+      - 'v*'
+    branches:
+      - master
+  pull_request:
+  workflow_call:
+
+jobs:
+  test_go:
+    name: Go tests
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5.0.0
+      - name: Install Go
+        uses: actions/setup-go@d35c59abb061a4a6fb18e82ac0862c26744d6ab5 # v5.5.0
+        with:
+          go-version: 1.25.x
+      - run: go build -o promu-intermediate
+      - run: make check_license style unused lint test build PROMU=./promu-intermediate
+      - run: rm -v promu promu-intermediate
+      - run: git diff --exit-code
+
+  build:
+    name: Build for common architectures
+    runs-on: ubuntu-latest
+    environment:
+        PROMU: ./promu-intermediate
+    if: |
+      !(github.event_name == 'push' && github.event.ref == 'refs/heads/master')
+      &&
+      !(github.event_name == 'push' && startsWith(github.ref, 'refs/tags/v'))
+    strategy:
+      matrix:
+        thread: [ 0, 1, 2 ]
+    steps:
+      - uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5.0.0
+      - name: Install Go
+        uses: actions/setup-go@d35c59abb061a4a6fb18e82ac0862c26744d6ab5 # v5.5.0
+        with:
+          go-version: 1.25.x
+      - run: go build -o promu-intermediate
+      - run: ./promu-intermediate crossbuild -v --parallelism 3 --parallelism-thread ${{ matrix.thread }}
+
+  publish_master:
+    name: Publish master branch artifacts
+    runs-on: ubuntu-latest
+    needs: [test_go, build, verify-example-configs]
+    environment:
+        PROMU: ./promu-intermediate
+    if: |
+      (github.repository == 'prometheus/promu')
+      &&
+      (github.event_name == 'push' && github.event.ref == 'refs/heads/master')
+    steps:
+      - uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5.0.0
+      - uses: prometheus/promci@443c7fc2397e946bc9f5029e313a9c3441b9b86d # v0.4.7
+      - run: go build -o promu-intermediate
+      - uses: ./.github/promci/actions/publish_main
+        with:
+          docker_hub_organization: prometheuscommunity
+          docker_hub_login: ${{ secrets.docker_hub_login }}
+          docker_hub_password: ${{ secrets.docker_hub_password }}
+          quay_io_organization: prometheuscommunity
+          quay_io_login: ${{ secrets.quay_io_login }}
+          quay_io_password: ${{ secrets.quay_io_password }}
+
+  publish_release:
+    name: Publish release artifacts
+    runs-on: ubuntu-latest
+    needs: [test_go, build, verify-example-configs]
+    environment:
+        PROMU: ./promu-intermediate
+    if: |
+      (github.repository == 'prometheus/promu')
+      &&
+      (github.event_name == 'push' && startsWith(github.ref, 'refs/tags/v0.'))
+    steps:
+      - uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5.0.0
+      - uses: prometheus/promci@443c7fc2397e946bc9f5029e313a9c3441b9b86d # v0.4.7
+      - run: go build -o promu-intermediate
+      - uses: ./.github/promci/actions/publish_release
+        with:
+          docker_hub_organization: prometheuscommunity
+          docker_hub_login: ${{ secrets.docker_hub_login }}
+          docker_hub_password: ${{ secrets.docker_hub_password }}
+          quay_io_organization: prometheuscommunity
+          quay_io_login: ${{ secrets.quay_io_login }}
+          quay_io_password: ${{ secrets.quay_io_password }}
+          github_token: ${{ secrets.PROMBOT_GITHUB_TOKEN }}