diff --git a/.github/workflows/publish.yml b/.github/workflows/publish.yml
index 7c86728..be07ce9 100644
--- a/.github/workflows/publish.yml
+++ b/.github/workflows/publish.yml
@@ -6,8 +6,14 @@ name: Publish Docker Image
 # documentation.
 
 on:
+    schedule:
+        - cron: "26 7 * * *"
     push:
         branches: ["main"]
+        # Publish semver tags as releases.
+        tags: ["v*.*.*"]
+    pull_request:
+        branches: ["main"]
 
 env:
     # Use docker.io for Docker Hub if empty
@@ -29,21 +35,38 @@ jobs:
             - name: Checkout repository
               uses: actions/checkout@v3
 
+            # Install the cosign tool except on PR
+            # https://github.com/sigstore/cosign-installer
+            - name: Install cosign
+              if: github.event_name != 'pull_request'
+              uses: sigstore/cosign-installer@6e04d228eb30da1757ee4e1dd75a0ec73a653e06 #v3.1.1
+              with:
+                  cosign-release: "v2.1.1"
+
             # Set up BuildKit Docker container builder to be able to build
             # multi-platform images and export cache
             # https://github.com/docker/setup-buildx-action
             - name: Set up Docker Buildx
               uses: docker/setup-buildx-action@f95db51fddba0c2d1ec667646a06c2ce06100226 # v3.0.0
 
-            # Login against a Docker registry
+            # Login against a Docker registry except on PR
             # https://github.com/docker/login-action
             - name: Log into registry ${{ env.REGISTRY }}
+              if: github.event_name != 'pull_request'
               uses: docker/login-action@343f7c4344506bcbf9b4de18042ae17996df046d # v3.0.0
               with:
                   registry: ${{ env.REGISTRY }}
                   username: ${{ github.actor }}
                   password: ${{ secrets.GITHUB_TOKEN }}
 
+            # Extract metadata (tags, labels) for Docker
+            # https://github.com/docker/metadata-action
+            - name: Extract Docker metadata
+              id: meta
+              uses: docker/metadata-action@96383f45573cb7f253c731d3b3ab81c87ef81934 # v5.0.0
+              with:
+                  images: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}
+
             # Build and push Docker image with Buildx (don't push on PR)
             # https://github.com/docker/build-push-action
             - name: Build and push Docker image
@@ -51,6 +74,23 @@ jobs:
               uses: docker/build-push-action@0565240e2d4ab88bba5387d719585280857ece09 # v5.0.0
               with:
                   context: .
-                  tags: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}:main
+                  push: ${{ github.event_name != 'pull_request' }}
+                  tags: ${{ steps.meta.outputs.tags }}
+                  labels: ${{ steps.meta.outputs.labels }}
                   cache-from: type=gha
                   cache-to: type=gha,mode=max
+
+            # Sign the resulting Docker image digest except on PRs.
+            # This will only write to the public Rekor transparency log when the Docker
+            # repository is public to avoid leaking data.  If you would like to publish
+            # transparency data even for private images, pass --force to cosign below.
+            # https://github.com/sigstore/cosign
+            - name: Sign the published Docker image
+              if: ${{ github.event_name != 'pull_request' }}
+              env:
+                  # https://docs.github.com/en/actions/security-guides/security-hardening-for-github-actions#using-an-intermediate-environment-variable
+                  TAGS: ${{ steps.meta.outputs.tags }}
+                  DIGEST: ${{ steps.build-and-push.outputs.digest }}
+              # This step uses the identity token to provision an ephemeral certificate
+              # against the sigstore community Fulcio instance.
+              run: echo "${TAGS}" | xargs -I {} cosign sign --yes {}@${DIGEST}
diff --git a/Dockerfile b/Dockerfile
index a9dc920..65c6268 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -15,6 +15,9 @@ RUN --mount=type=cache,target=/usr/local/cargo/registry \
 # Runtime image
 FROM rust:latest
 
+LABEL org.opencontainers.image.source=https://github.com/kixelated/moq-rs
+LABEL org.opencontainers.image.licenses=MIT OR Apache-2.0
+
 # Fly.io entrypoint
 ADD fly-relay.sh .