diff --git a/.circleci/config.yml b/.circleci/config.yml
deleted file mode 100644
index fa076dd736c..00000000000
--- a/.circleci/config.yml
+++ /dev/null
@@ -1,223 +0,0 @@
-version: 2.1
-
-orbs:
-  node: circleci/node@7.1.1
-  docker: circleci/docker@1.5.0
-  codecov: codecov/codecov@5.0.3
-  gcp-cli: circleci/gcp-cli@3.3.2
-
-# Reusable commands for Docker jobs
-commands:
-  create-version-json:
-    description: "Create version.json for Dockerflow"
-    steps:
-      - run:
-          name: Create version.json
-          command: |
-            # create a version.json per https://github.com/mozilla-services/Dockerflow/blob/master/docs/version_object.md
-            printf '{"commit":"%s","version":"%s","source":"https://github.com/%s/%s","build":"%s"}\n' \
-            "$CIRCLE_SHA1" \
-            "$CIRCLE_TAG" \
-            "$CIRCLE_PROJECT_USERNAME" \
-            "$CIRCLE_PROJECT_REPONAME" \
-            "$CIRCLE_BUILD_URL" > version.json
-
-  setup-docker-env:
-    description: "Setup Docker environment"
-    steps:
-      - setup_remote_docker:
-          version: docker24
-      - create-version-json
-
-  build-docker-image:
-    description: "Build Docker image"
-    steps:
-      - run:
-          name: Build Docker image
-          command: DOCKER_BUILDKIT=1 docker build -f docker/Dockerfile -t app:build .
-
-  deploy-to-dockerhub:
-    description: "Deploy to Docker Hub"
-    steps:
-      - run:
-          name: Deploy to Dockerhub
-          command: |
-            echo $DOCKER_PASS | docker login -u $DOCKER_USER --password-stdin
-
-            # Function to tag and push
-            tag_and_push() {
-              local tag=$1
-              docker tag app:build "${DOCKERHUB_REPO}:${tag}"
-              docker push "${DOCKERHUB_REPO}:${tag}"
-            }
-
-            if [ "${CIRCLE_BRANCH}" == "master" ]; then
-              tag_and_push "latest"
-              tag_and_push "${CIRCLE_BRANCH}-${CIRCLE_SHA1}"
-            elif [ "${CIRCLE_BRANCH}" == "prototype" ]; then
-              tag_and_push "${CIRCLE_BRANCH}-${CIRCLE_SHA1}"
-            elif [ ! -z "${CIRCLE_TAG}" ]; then
-              echo "Deploying release tag: ${DOCKERHUB_REPO}:${CIRCLE_TAG}"
-              tag_and_push "${CIRCLE_TAG}"
-            fi
-
-  deploy-to-gcp-gar:
-    description: "Deploy to GCP Artifact Registry"
-    steps:
-      - gcp-cli/setup:
-          use_oidc: true
-          google_project_number: GCP_WIP_PROJECT_NUMBER
-          google_project_id: GCP_PROJECT_ID_OF_GCP_GAR
-          workload_identity_pool_id: GCP_WIP_ID
-          workload_identity_pool_provider_id: GCP_WIP_PROVIDER_ID
-          service_account_email: GCP_GAR_PUSHER_SERVICE_ACCOUNT_EMAIL
-      - run:
-          name: Configure Docker for GAR
-          command: gcloud auth configure-docker ${GCP_GAR_REGISTRY}
-      - run:
-          name: Deploy to GCP GAR
-          command: |
-            GCP_GAR_REPO="${GCP_GAR_REGISTRY}/${GCP_PROJECT_ID_OF_GCP_GAR}/treeherder-prod/treeherder"
-
-            # Function to tag and push to GCP GAR
-            tag_and_push_gar() {
-              local tag=$1
-              docker tag app:build "${GCP_GAR_REPO}:${tag}"
-              docker push "${GCP_GAR_REPO}:${tag}"
-            }
-
-            if [ "${CIRCLE_BRANCH}" == "master" ]; then
-              tag_and_push_gar "latest"
-              tag_and_push_gar "${CIRCLE_BRANCH}-${CIRCLE_SHA1}"
-            elif [ "${CIRCLE_BRANCH}" == "prototype" ]; then
-              tag_and_push_gar "${CIRCLE_BRANCH}-${CIRCLE_SHA1}"
-            elif [ ! -z "${CIRCLE_TAG}" ]; then
-              echo "Deploying release tag: ${GCP_GAR_REPO}:${CIRCLE_TAG}"
-              tag_and_push_gar "${CIRCLE_TAG}"
-            fi
-
-jobs:
-  javascript-tests:
-    executor:
-      name: node/default
-      # The Node version here should be compatible with `package.json` engines.
-      # Note: cimg/node requires at least a minor version (e.g., '22.0'), not just major version
-      tag: '22.0'
-    steps:
-      - checkout
-      - run:
-          name: Install pnpm
-          command: sudo corepack enable && corepack prepare pnpm@9.15.0 --activate
-      - run:
-          name: Install dependencies
-          command: pnpm install --frozen-lockfile
-      - run:
-          command: pnpm lint
-          name: Run linting
-      - run:
-          command: pnpm markdownlint
-          name: Check markdown linting
-      - run:
-          command: pnpm test:ci
-          name: Run Jest tests
-      - codecov/upload
-
-  builds:
-    docker:
-      - image: 'cimg/python:3.10-node'
-    steps:
-      - checkout
-      - run: pip install tox
-      - run:
-          command: tox -e docs
-          name: Build docs
-      - run:
-          command: tox -e linters
-          name: Run linters
-
-  python-tests-general:
-    machine:
-      image: default
-    steps:
-      - checkout
-      - docker/install-docker-compose:
-          version: 1.29.2
-      - run:
-          name: Run tests and coverage within Docker container
-          command: |
-            pip install --upgrade pip
-            pip install tox
-            tox -e docker-general
-      - codecov/upload
-
-  python-tests-perf:
-    machine:
-      image: default
-    steps:
-      - checkout
-      - docker/install-docker-compose:
-          version: 1.29.2
-      - run:
-          name: Run tests and coverage within Docker container
-          command: |
-            pip install --upgrade pip
-            pip install tox
-            tox -e docker-perf
-      - codecov/upload
-
-  python-tests-frontend:
-    machine:
-      image: default
-    steps:
-      - checkout
-      - docker/install-docker-compose:
-          version: 1.29.2
-      - run:
-          name: Run tests and coverage within Docker container
-          command: |
-            pip install --upgrade pip
-            pip install tox
-            tox -e docker-frontend
-      - codecov/upload
-
-  test-docker-build:
-    docker:
-      - image: cimg/base:current
-    environment:
-      # Required for compatibility between newer Docker client and docker24 remote daemon
-      DOCKER_API_VERSION: "1.43"
-    steps:
-      - checkout
-      - setup-docker-env
-      - build-docker-image
-
-  deploy:
-    docker:
-      - image: cimg/base:current
-    environment:
-      # Required for compatibility between newer Docker client and docker24 remote daemon
-      DOCKER_API_VERSION: "1.43"
-    steps:
-      - checkout
-      - setup-docker-env
-      - build-docker-image
-      - deploy-to-dockerhub
-      - deploy-to-gcp-gar
-
-workflows:
-  run-tests:
-    jobs:
-      - javascript-tests
-      - builds
-      - python-tests-frontend
-      - python-tests-general
-      - python-tests-perf
-      - test-docker-build
-      - deploy:
-          filters:
-            tags:
-              only: /.*/
-            branches:
-              only:
-                - master
-                - prototype
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
new file mode 100644
index 00000000000..b84979cafd7
--- /dev/null
+++ b/.github/workflows/ci.yml
@@ -0,0 +1,146 @@
+name: CI
+
+on:
+  push:
+  pull_request:
+
+jobs:
+  javascript-tests:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: pnpm/action-setup@v4
+      - uses: actions/setup-node@v4
+        with:
+          node-version: '22.0'
+          cache: 'pnpm'
+      - run: pnpm install --frozen-lockfile
+      - run: pnpm lint
+        name: Run linting
+      - run: pnpm markdownlint
+        name: Check markdown linting
+      - run: pnpm test:ci
+        name: Run Jest tests
+      - uses: codecov/codecov-action@v5
+
+  builds:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-python@v5
+        with:
+          python-version: '3.10'
+      - run: pip install tox
+      - run: tox -e docs
+        name: Build docs
+      - run: tox -e linters
+        name: Run linters
+
+  python-tests-general:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-python@v5
+        with:
+          python-version: '3.10'
+      # tox.ini calls docker-compose (v1 CLI); ubuntu-latest only ships the v2 plugin.
+      # This shim bridges the two so existing scripts work unmodified.
+      - name: Install docker-compose compatibility shim
+        run: printf '#!/bin/sh\nexec docker compose "$@"\n' | sudo tee /usr/local/bin/docker-compose && sudo chmod +x /usr/local/bin/docker-compose
+      - run: pip install tox
+      - name: Run tests and coverage within Docker container
+        run: tox -e docker-general
+      - uses: codecov/codecov-action@v5
+
+  python-tests-perf:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-python@v5
+        with:
+          python-version: '3.10'
+      - name: Install docker-compose compatibility shim
+        run: printf '#!/bin/sh\nexec docker compose "$@"\n' | sudo tee /usr/local/bin/docker-compose && sudo chmod +x /usr/local/bin/docker-compose
+      - run: pip install tox
+      - name: Run tests and coverage within Docker container
+        run: tox -e docker-perf
+      - uses: codecov/codecov-action@v5
+
+  python-tests-frontend:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-python@v5
+        with:
+          python-version: '3.10'
+      - name: Install docker-compose compatibility shim
+        run: printf '#!/bin/sh\nexec docker compose "$@"\n' | sudo tee /usr/local/bin/docker-compose && sudo chmod +x /usr/local/bin/docker-compose
+      - run: pip install tox
+      - name: Run tests and coverage within Docker container
+        run: tox -e docker-frontend
+      - uses: codecov/codecov-action@v5
+
+  test-docker-build:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: ./.github/actions/build-docker
+
+  deploy:
+    needs: [javascript-tests, builds, python-tests-general, python-tests-perf, python-tests-frontend, test-docker-build]
+    if: github.event_name == 'push' && (github.ref == 'refs/heads/master' || github.ref == 'refs/heads/prototype' || startsWith(github.ref, 'refs/tags/'))
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+      id-token: write
+    steps:
+      - uses: actions/checkout@v4
+      - uses: ./.github/actions/build-docker
+
+      # Deploy to Docker Hub
+      - name: Login to Docker Hub
+        run: echo "${{ secrets.DOCKER_PASS }}" | docker login -u "${{ secrets.DOCKER_USER }}" --password-stdin
+      - name: Tag and push to Docker Hub
+        run: |
+          tag_and_push() {
+            local tag=$1
+            docker tag app:build "${{ secrets.DOCKERHUB_REPO }}:${tag}"
+            docker push "${{ secrets.DOCKERHUB_REPO }}:${tag}"
+          }
+
+          if [ "${{ github.ref }}" == "refs/heads/master" ]; then
+            tag_and_push "latest"
+            tag_and_push "master-${GITHUB_SHA}"
+          elif [ "${{ github.ref }}" == "refs/heads/prototype" ]; then
+            tag_and_push "prototype-${GITHUB_SHA}"
+          elif [[ "${{ github.ref }}" == refs/tags/* ]]; then
+            tag_and_push "${{ github.ref_name }}"
+          fi
+
+      # Deploy to GCP Artifact Registry
+      - id: gcp-auth
+        uses: google-github-actions/auth@v2
+        with:
+          workload_identity_provider: projects/${{ secrets.GCP_WIP_PROJECT_NUMBER }}/locations/global/workloadIdentityPools/${{ secrets.GCP_WIP_ID }}/providers/${{ secrets.GCP_WIP_PROVIDER_ID }}
+          service_account: ${{ secrets.GCP_GAR_PUSHER_SERVICE_ACCOUNT_EMAIL }}
+      - uses: google-github-actions/setup-gcloud@v2
+      - name: Configure Docker for GAR
+        run: gcloud auth configure-docker ${{ secrets.GCP_GAR_REGISTRY }}
+      - name: Tag and push to GCP GAR
+        run: |
+          GCP_GAR_REPO="${{ secrets.GCP_GAR_REGISTRY }}/${{ secrets.GCP_PROJECT_ID_OF_GCP_GAR }}/treeherder-prod/treeherder"
+
+          tag_and_push_gar() {
+            local tag=$1
+            docker tag app:build "${GCP_GAR_REPO}:${tag}"
+            docker push "${GCP_GAR_REPO}:${tag}"
+          }
+
+          if [ "${{ github.ref }}" == "refs/heads/master" ]; then
+            tag_and_push_gar "latest"
+            tag_and_push_gar "master-${GITHUB_SHA}"
+          elif [ "${{ github.ref }}" == "refs/heads/prototype" ]; then
+            tag_and_push_gar "prototype-${GITHUB_SHA}"
+          elif [[ "${{ github.ref }}" == refs/tags/* ]]; then
+            tag_and_push_gar "${{ github.ref_name }}"
+          fi
diff --git a/README.md b/README.md
index f02d67b271a..67a48b8b575 100644
--- a/README.md
+++ b/README.md
@@ -1,7 +1,7 @@
 # Treeherder
 
 [![What's Deployed](https://img.shields.io/badge/whatsdeployed-prototype,stage,prod-green.svg)](https://whatsdeployed.io/s/BIY/Mozilla/Treeherder)
-[![Build Status](https://circleci.com/gh/mozilla/treeherder.svg?branch=master&style=shield)](https://app.circleci.com/pipelines/github/mozilla/treeherder)
+[![Build Status](https://github.com/mozilla/treeherder/actions/workflows/ci.yml/badge.svg)](https://github.com/mozilla/treeherder/actions/workflows/ci.yml)
 ![Node dependencies Status](https://shields.io/librariesio/github/mozilla/treeherder)
 [![Documentation Status](https://readthedocs.org/projects/treeherder/badge/?version=latest)](https://treeherder.readthedocs.io/?badge=latest)
 [![Code style: black](https://img.shields.io/badge/code%20style-black-000000.svg)](https://github.com/psf/black)
diff --git a/ui/contribute.json b/ui/contribute.json
index a9194d8b825..1854f427f80 100644
--- a/ui/contribute.json
+++ b/ui/contribute.json
@@ -4,7 +4,7 @@
   "repository": {
     "url": "https://github.com/mozilla/treeherder",
     "license": "MPL2",
-    "tests": "https://app.circleci.com/pipelines/github/mozilla/treeherder"
+    "tests": "https://github.com/mozilla/treeherder/actions"
   },
   "participate": {
     "home": "https://wiki.mozilla.org/EngineeringProductivity/Projects/Treeherder",