diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
index 8f863d2..d1dbf96 100644
--- a/.github/workflows/ci.yaml
+++ b/.github/workflows/ci.yaml
@@ -15,6 +15,7 @@ jobs:
     uses: peacefulstudio/github-actions/.github/workflows/csharp-ci.yaml@v2
     with:
       dotnet-version: '10.0.x'
+      artifact-prefix: csharp
       build-matrix: >-
         [{"name":"ubuntu-amd64","runner":"ubuntu-latest","coverage":true},
          {"name":"ubuntu-arm64","runner":"ubuntu-24.04-arm","coverage":false},
@@ -23,15 +24,47 @@ jobs:
          {"name":"macos-arm64","runner":"macos-latest","coverage":false},
          {"name":"macos-amd64","runner":"macos-15-intel","coverage":false}]
 
+  badges:
+    needs: [csharp-ci, jvm-helper-ci, assemble-badge-data]
+    if: ${{ github.ref == 'refs/heads/main' && !cancelled() }}
+    permissions:
+      contents: write
+    uses: peacefulstudio/github-actions/.github/workflows/update-badges.yaml@v2
+    with:
+      coverage-data: >-
+        [{"slug":"csharp","label":"coverage (C#)","percent":"${{ needs.csharp-ci.outputs.coverage }}"},
+         {"slug":"scala","label":"coverage (Scala)","percent":"${{ needs.jvm-helper-ci.outputs.coverage }}"}]
+      matrix-data: ${{ needs.assemble-badge-data.outputs.matrix-data }}
+
   jvm-helper-ci:
     uses: peacefulstudio/github-actions/.github/workflows/scala-ci.yaml@v2
     with:
       working-directory: jvm-helper
+      artifact-prefix: scala
       # No windows-arm64 shard: Maven Central publishes no windows-aarch_64 protoc
       # binary at any version, so sbt-protoc cannot resolve a compiler there.
       build-matrix: >-
-        [{"name":"ubuntu-amd64","runner":"ubuntu-latest","coverage":false},
+        [{"name":"ubuntu-amd64","runner":"ubuntu-latest","coverage":true},
          {"name":"ubuntu-arm64","runner":"ubuntu-24.04-arm","coverage":false},
          {"name":"windows-amd64","runner":"windows-latest","coverage":false},
          {"name":"macos-arm64","runner":"macos-latest","coverage":false},
          {"name":"macos-amd64","runner":"macos-15-intel","coverage":false}]
+
+  assemble-badge-data:
+    needs: [csharp-ci, jvm-helper-ci]
+    if: ${{ github.ref == 'refs/heads/main' && !cancelled() }}
+    runs-on: ubuntu-latest
+    outputs:
+      matrix-data: ${{ steps.merge.outputs.matrix-data }}
+    steps:
+      - name: Merge matrix-status by language
+        id: merge
+        env:
+          CSHARP_STATUS: ${{ needs.csharp-ci.outputs.matrix-status }}
+          SCALA_STATUS: ${{ needs.jvm-helper-ci.outputs.matrix-status }}
+        run: |
+          set -euo pipefail
+          csharp="$(jq -c '[.[] + {lang:"csharp"}]' <<<"${CSHARP_STATUS:-[]}")"
+          scala="$(jq -c '[.[] + {lang:"scala"}]' <<<"${SCALA_STATUS:-[]}")"
+          merged="$(jq -cn --argjson a "$csharp" --argjson b "$scala" '$a + $b')"
+          echo "matrix-data=$merged" >> "$GITHUB_OUTPUT"
diff --git a/README.md b/README.md
index e888ccb..2a49ad6 100644
--- a/README.md
+++ b/README.md
@@ -1,12 +1,37 @@
 # Daml C# Code Generator
 
 [![CI](https://github.com/peacefulstudio/daml-codegen-csharp/actions/workflows/ci.yaml/badge.svg)](https://github.com/peacefulstudio/daml-codegen-csharp/actions/workflows/ci.yaml)
+[![Release](https://img.shields.io/github/v/release/peacefulstudio/daml-codegen-csharp?label=latest%20stable)](https://github.com/peacefulstudio/daml-codegen-csharp/releases/latest)
+[![latest preview](https://img.shields.io/github/v/release/peacefulstudio/daml-codegen-csharp?include_prereleases&label=latest%20preview)](https://github.com/peacefulstudio/daml-codegen-csharp/releases)
 [![License](https://img.shields.io/badge/License-Apache_2.0-blue.svg)](https://opensource.org/licenses/Apache-2.0)
 [![.NET](https://img.shields.io/badge/.NET-10.0-white.svg)](https://dotnet.microsoft.com/)
 
 Generates strongly-typed C# from Daml `.dar` archives so .NET applications can
 talk to a Canton/Daml ledger with full type safety.
 
+## Platform Support
+
+CI builds and tests on every supported OS × architecture. Each badge reflects the latest `main` run.
+
+**C# (`Daml.Codegen.CSharp`)**
+
+| Ubuntu | Windows | macOS |
+|---|---|---|
+| [![ubuntu amd64](https://img.shields.io/endpoint?url=https://raw.githubusercontent.com/peacefulstudio/daml-codegen-csharp/badges/ci-csharp-ubuntu-amd64.json)](https://github.com/peacefulstudio/daml-codegen-csharp/actions/workflows/ci.yaml) | [![windows amd64](https://img.shields.io/endpoint?url=https://raw.githubusercontent.com/peacefulstudio/daml-codegen-csharp/badges/ci-csharp-windows-amd64.json)](https://github.com/peacefulstudio/daml-codegen-csharp/actions/workflows/ci.yaml) | [![macos amd64](https://img.shields.io/endpoint?url=https://raw.githubusercontent.com/peacefulstudio/daml-codegen-csharp/badges/ci-csharp-macos-amd64.json)](https://github.com/peacefulstudio/daml-codegen-csharp/actions/workflows/ci.yaml) |
+| [![ubuntu arm64](https://img.shields.io/endpoint?url=https://raw.githubusercontent.com/peacefulstudio/daml-codegen-csharp/badges/ci-csharp-ubuntu-arm64.json)](https://github.com/peacefulstudio/daml-codegen-csharp/actions/workflows/ci.yaml) | [![windows arm64](https://img.shields.io/endpoint?url=https://raw.githubusercontent.com/peacefulstudio/daml-codegen-csharp/badges/ci-csharp-windows-arm64.json)](https://github.com/peacefulstudio/daml-codegen-csharp/actions/workflows/ci.yaml) | [![macos arm64](https://img.shields.io/endpoint?url=https://raw.githubusercontent.com/peacefulstudio/daml-codegen-csharp/badges/ci-csharp-macos-arm64.json)](https://github.com/peacefulstudio/daml-codegen-csharp/actions/workflows/ci.yaml) |
+
+**Scala/JVM helper**
+
+| Ubuntu | Windows | macOS |
+|---|---|---|
+| [![ubuntu amd64](https://img.shields.io/endpoint?url=https://raw.githubusercontent.com/peacefulstudio/daml-codegen-csharp/badges/ci-scala-ubuntu-amd64.json)](https://github.com/peacefulstudio/daml-codegen-csharp/actions/workflows/ci.yaml) | [![windows amd64](https://img.shields.io/endpoint?url=https://raw.githubusercontent.com/peacefulstudio/daml-codegen-csharp/badges/ci-scala-windows-amd64.json)](https://github.com/peacefulstudio/daml-codegen-csharp/actions/workflows/ci.yaml) | [![macos amd64](https://img.shields.io/endpoint?url=https://raw.githubusercontent.com/peacefulstudio/daml-codegen-csharp/badges/ci-scala-macos-amd64.json)](https://github.com/peacefulstudio/daml-codegen-csharp/actions/workflows/ci.yaml) |
+| [![ubuntu arm64](https://img.shields.io/endpoint?url=https://raw.githubusercontent.com/peacefulstudio/daml-codegen-csharp/badges/ci-scala-ubuntu-arm64.json)](https://github.com/peacefulstudio/daml-codegen-csharp/actions/workflows/ci.yaml) | ![windows arm64 not supported](https://img.shields.io/badge/arm64-not%20supported-lightgrey?logo=data:image/svg+xml;base64,PHN2ZyB4bWxucz0iaHR0cDovL3d3dy53My5vcmcvMjAwMC9zdmciIHZpZXdCb3g9IjAgMCAyNCAyNCI+PHBhdGggZmlsbD0id2hpdGUiIGQ9Ik0wIDMuNDQ5TDkuNzUgMi4xdjkuNDUxSDBtMTAuOTQ5LTkuNjAyTDI0IDB2MTEuNEgxMC45NDlNMCAxMi42aDkuNzV2OS40NTFMMCAyMC42OTlNMTAuOTQ5IDEyLjZIMjRWMjRsLTEyLjktMS44MDEiLz48L3N2Zz4=&logoColor=white) | [![macos arm64](https://img.shields.io/endpoint?url=https://raw.githubusercontent.com/peacefulstudio/daml-codegen-csharp/badges/ci-scala-macos-arm64.json)](https://github.com/peacefulstudio/daml-codegen-csharp/actions/workflows/ci.yaml) |
+
+## Coverage
+
+[![coverage (C#)](https://img.shields.io/endpoint?url=https://raw.githubusercontent.com/peacefulstudio/daml-codegen-csharp/badges/coverage-csharp.json)](https://github.com/peacefulstudio/daml-codegen-csharp/actions/workflows/ci.yaml)
+[![coverage (Scala)](https://img.shields.io/endpoint?url=https://raw.githubusercontent.com/peacefulstudio/daml-codegen-csharp/badges/coverage-scala.json)](https://github.com/peacefulstudio/daml-codegen-csharp/actions/workflows/ci.yaml)
+
 ## Status
 
 Active. Curated public releases land here; ongoing development happens
@@ -98,6 +123,9 @@ var submission = CommandsSubmission.Single(createCmd)
 
 ## NuGet Packages
 
+[![latest stable](https://img.shields.io/github/v/release/peacefulstudio/daml-codegen-csharp?label=latest%20stable)](https://github.com/peacefulstudio/daml-codegen-csharp/releases/latest)
+[![latest](https://img.shields.io/github/v/release/peacefulstudio/daml-codegen-csharp?include_prereleases&label=latest)](https://github.com/peacefulstudio/daml-codegen-csharp/releases)
+
 The following packages are published to NuGet.org, starting with
 `0.1.8-preview.1` (earlier versions in the CHANGELOG were internal
 milestones and never reached a public feed):