diff --git a/.dockerfilelintrc b/.dockerfilelintrc
index e691449..b56beef 100644
--- a/.dockerfilelintrc
+++ b/.dockerfilelintrc
@@ -2,4 +2,5 @@
 rules:
   apt-get_missing_rm: off
   apt-get_recommends: off
+  apt-get-upgrade: off
   sudo_usage: off
diff --git a/.github/workflows/docker_build.yml b/.github/workflows/docker_build.yml
index ceb8cb9..e1f2776 100644
--- a/.github/workflows/docker_build.yml
+++ b/.github/workflows/docker_build.yml
@@ -14,6 +14,8 @@ on:
 env:
   REGISTRY: ghcr.io
   IMAGE_PATH: ghcr.io/${{ github.repository }}
+  TARFILE_NAME: image.tar
+
 
 jobs:
   tests:
@@ -25,41 +27,76 @@ jobs:
       - name: Static Analysis
         uses: pre-commit/action@v3.0.0
 
-      - name: Build (but Don't Push) Docker Image
-        uses: docker/build-push-action@v5
+      - name: Extract metadata (tags, labels) for Docker
+        id: meta
+        uses: docker/metadata-action@v4.1.1
+        with:
+          images: ${{ env.IMAGE_PATH }}
+          tags: |
+            type=ref,event=branch
+            type=ref,event=pr
+            type=semver,pattern={{version}} # major.minor.patch
+            type=semver,pattern={{major}}.{{minor}}
+
+      - name: Check that build works, save for scanning, but don't push yet
+        uses: docker/build-push-action@v6.4.0
         with:
           context: .
           push: false
+          outputs: type=tar,dest=${{ env.TARFILE_NAME }}
+          tags: ${{ steps.meta.outputs.tags }}
+          labels: ${{ steps.meta.outputs.labels }}
+
+      - name: Upload tarball for use by Trivy job
+        uses: actions/upload-artifact@v4
+        with:
+          name: ${{ env.TARFILE_NAME }}
+          path: ${{ env.TARFILE_NAME }}
 
-  build-and-push-image:
+    outputs:
+      meta_json: ${{ steps.meta.outputs.json }}
+      tarfile_artifact: ${{ env.TARFILE_NAME }}
+
+  trivy-scan:
+    needs: tests
+    uses: "./.github/workflows/trivy.yml"
+    with:
+      SOURCE_TYPE: tar
+      IMAGE_NAME: image-name
+      TARFILE_NAME: ${{ needs.tests.outputs.tarfile_artifact }}
+      EXIT_CODE: 1
+
+  push-image:
     if: ${{ github.event_name == 'push' }}
-    needs: [tests]
+    needs: [tests, trivy-scan]
     runs-on: ubuntu-latest
     permissions:
       contents: read
       packages: write
+    strategy:
+      matrix:
+        value: ${{ fromJSON(needs.tests.outputs.meta_json).tags }}
 
     steps:
-      - name: Checkout repository
-        uses: actions/checkout@v4
+      - name: Download tar file
+        id: tar-download
+        uses: actions/download-artifact@v4
+        with:
+          name: ${{ env.TARFILE_NAME }}
+          path: /tmp
 
-      - name: Log in to the Container registry
-        uses: docker/login-action@v2.1.0
+      - name: Load Docker image from tar
+        run: cat
+          ${{ steps.tar-download.outputs.download-path}}/${{ env.TARFILE_NAME}}
+          | docker import - ${{ matrix.value }}
+
+      - name: Login to GitHub Container Registry
+        uses: docker/login-action@v2
         with:
-          registry: ${{ env.REGISTRY }}
+          registry: ghcr.io
           username: ${{ github.actor }}
           password: ${{ secrets.GITHUB_TOKEN }}
 
-      - name: Extract metadata (tags, labels) for Docker
-        id: meta
-        uses: docker/metadata-action@v4.1.1
-        with:
-          images: ${{ env.IMAGE_PATH }}
-
-      - name: Build and push Docker image
-        uses: docker/build-push-action@v5
-        with:
-          context: .
-          push: true
-          tags: ${{ steps.meta.outputs.tags }}
-          labels: ${{ steps.meta.outputs.labels }}
+      - name: Push Docker image
+        run: docker push ${{ matrix.value }}
+...
diff --git a/.github/workflows/trivy.yml b/.github/workflows/trivy.yml
new file mode 100644
index 0000000..da967cb
--- /dev/null
+++ b/.github/workflows/trivy.yml
@@ -0,0 +1,90 @@
+---
+#
+# This workflow runs Trivy on a Docker image
+# It can pull the image from a container registry
+# or download a tar file.  The latter is used
+# to check a container image prior to publishing
+# to the registry.
+
+name: Run Trivy on a Docker image and push results to GitHub
+
+on:
+  workflow_call:
+    inputs:
+      SOURCE_TYPE: # 'tar' or 'image'
+        required: true
+        type: string
+      TARFILE_NAME: # only used if SOURCE_TYPE=='tar'
+        required: false
+        type: string
+      IMAGE_NAME:
+        required: true
+        type: string
+      EXIT_CODE: # return code for failed scan. 0 means OK
+        required: false
+        type: number
+        default: 0
+
+env:
+  sarif_file_name: trivy-results.sarif
+
+jobs:
+  trivy:
+    name: Trivy
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+      security-events: write
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Download tar file
+        id: tar-download
+        uses: actions/download-artifact@v4
+        if: ${{ inputs.SOURCE_TYPE == 'tar' }}
+        with:
+          name: ${{ inputs.TARFILE_NAME }}
+          path: /tmp
+
+      - name: load docker image from tar file
+        if: ${{ inputs.SOURCE_TYPE == 'tar' }}
+        run: cat ${{ steps.tar-download.outputs.download-path
+          }}/${{ inputs.TARFILE_NAME
+          }} | docker import - ${{ inputs.IMAGE_NAME }}
+
+      - name: Run Trivy vulnerability scanner for any major issues
+        uses: aquasecurity/trivy-action@0.24.0
+        id: trivy
+        with:
+          image-ref: ${{ inputs.IMAGE_NAME }}
+          ignore-unfixed: true # skip vul'ns for which there is no fix
+          # list files to skip, each with a justification
+          skip-files: |
+            /usr/local/lib/R/site-library/gargle/extdata/fake_service_account.json
+            /usr/local/lib/R/site-library/openssl/doc/keys.html
+          # fake_service_account.json is a fake account that gets flagged as a credentials file
+          # keys.html is a documentation file that appears to contain cred's
+          severity: 'CRITICAL,HIGH'
+          format: 'sarif'
+          # only output findings for configured severities
+          limit-severities-for-sarif: true
+          output: ${{ env.sarif_file_name  }}
+          exit-code: ${{ inputs.EXIT_CODE }}
+
+      - name: Upload Trivy scan results to GitHub Security tab
+        uses: github/codeql-action/upload-sarif@v3.25.12
+        # This is the recommended way to upload scan results
+        # after Trivy exits with HIGH/CRITICAL findings
+        # See https://github.com/aquasecurity/trivy-action?\
+        # tab=readme-ov-file#using-trivy-with-github-code-scanning
+        # Note that here instead of using `always()` which would
+        # allow the step to run if *any* preceeding step failed,
+        # this logic ensures that the step ony runs if all steps
+        # succeed or if only  the 'trivy' step fails.
+        if: ${{ success() || steps.trivy.conclusion=='failure' }}
+        with:
+          sarif_file: ${{ env.sarif_file_name  }}
+          wait-for-processing: true
+...
diff --git a/.github/workflows/trivy_periodic_image_scan.yml b/.github/workflows/trivy_periodic_image_scan.yml
new file mode 100644
index 0000000..ce18a9f
--- /dev/null
+++ b/.github/workflows/trivy_periodic_image_scan.yml
@@ -0,0 +1,35 @@
+---
+#
+# This workflow scans the published container images
+# for new vulnerabilities daily, publishing findings.
+# Findings will be associated with the 'main' branch
+# of the repo' in the GitHub Security tab.
+#
+name: Trivy Periodic Image Scan
+
+on:
+  schedule:
+    # run daily
+    - cron: "0 0 * * *"
+
+jobs:
+  to-lower-case:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Ensure image name is lower case
+        id: repo_name
+        uses: vishalmamidi/lowercase-action@v1
+        with:
+          string: ghcr.io/${{ github.repository }}:main
+    outputs:
+      lowercase-repo-name: ${{ steps.repo_name.outputs.lowercase }}
+
+  periodic-scan:
+    needs: lower-case
+    uses: "./.github/workflows/trivy.yml"
+    with:
+      SOURCE_TYPE: image
+      # While GitHub repo's can be mixed (upper and lower) case,
+      # Docker images can only be lower case
+      IMAGE_NAME: ${{ needs.to-lower-case.outputs.lowercase-repo-name }}
+...
diff --git a/.trivyignore b/.trivyignore
new file mode 100644
index 0000000..fb8ac81
--- /dev/null
+++ b/.trivyignore
@@ -0,0 +1,12 @@
+#
+# List vulnerabilities flagged by Trivy but for which
+# the affected code is not used or the risk is acceptable.
+# Enter the ID of the vulnerability along with the
+# justification as comment, for example:
+#
+# # Accept the risk
+# CVE-2018-14618
+#
+# More here:
+# https://aquasecurity.github.io/trivy/v0.22.0/vulnerability/examples/filter/
+#
diff --git a/.yamllint b/.yamllint
new file mode 100644
index 0000000..5a6a292
--- /dev/null
+++ b/.yamllint
@@ -0,0 +1,7 @@
+extends: default
+
+rules:
+  # allow long lines, needed for long file paths
+  line-length:
+    max: 200
+    level: error
diff --git a/Dockerfile b/Dockerfile
index f3bfcf7..2233b02 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,9 +1,10 @@
-FROM rocker/rstudio:4.3.2
+FROM rocker/rstudio:4.4.1
 
 # no login required
 ENV DISABLE_AUTH=true
 
 RUN apt-get -y update && \
+apt-get -y upgrade && \
 apt-get -y install libpng-dev \
 python3 \
 python3-pip \
diff --git a/README.md b/README.md
index f04afcf..cff5de6 100644
--- a/README.md
+++ b/README.md
@@ -8,5 +8,28 @@ To run:
 
 
 ```
-docker run -d -p 8787:8787 ghcr.io/sage-bionetworks-it/rstudio-service-catalog:v1.0.0
+docker run -d -p 8787:8787 ghcr.io/sage-bionetworks-it/rstudio-service-catalog:1.0.0
 ```
+
+## Versioning
+
+Semantic versioning is used and containers are tagged based on GitHub tags: If a tag,
+1.2.3 is pushed to GitHub then a container image is built with tags `1.2.3` as well as `1.2`.
+Thus the `major.minor` tag is overwritten when the repo' is patched.
+
+
+## Security
+
+Trivy is run on each built container and they will not be published
+to `ghcr.io` if any CRITICAL or HIGH
+vulnerabilites are found.  Trivy is also run daily to check for new
+vulnerabilities in existing images.  So periodic review of new findings
+is needed:  Go to the Security tab in GitHub, select Code Scanning at left,
+and then select Branch > Main to check for new findings.  To suppress
+false positives, either:
+
+- Enter the CVE in `.trivyignore`, or
+
+- Enter the file to skip while scanning in the `trivy.yml` workflow.
+
+In either case, add a comment justifying why the finding is suppressed.