# Flutter SDK Docker Images
Lightweight Flutter SDK images for CI/CD pipelines. Built on [Wolfi](https://wolfi.dev), a security-focused Linux distribution designed for containers.
## Images
| Variant | Use Case | Size | Arch |
|---------|----------|------|------|
| 
| Web/WASM builds | 
| 
|
| 
| Android APK/AAB builds | 
| |
| 
| Linux desktop builds | 
| |
## Why Wolfi?
[Wolfi](https://wolfi.dev) is a lightweight Linux distribution built specifically for containers. It provides:
- **Minimal footprint** - Only essential packages, nothing extra
- **Daily security updates** - Patches applied quickly
- **Designed for containers** - No legacy cruft from traditional distros
## Features
- **Lightweight** - Optimized for fast CI/CD pulls
- **Secure** - Built on Wolfi with continuous vulnerability scanning
- **Multi-arch** - Supports both `linux/amd64` and `linux/arm64`
- **Non-root** - Runs as unprivileged user (UID 65532)
- **Supply chain security** - SBOM and SLSA provenance attestations included
## Dockerfile Examples
### Web App (WASM)
```dockerfile
FROM svrnty/flutter-sdk:web-latest AS build
WORKDIR /app
COPY . .
RUN flutter pub get && flutter build web --wasm --release
# Cache-busting: append version to JS/WASM references
RUN VERSION=$(date +%s) && cd build/web && \
sed -i "s|flutter_bootstrap\.js\"|flutter_bootstrap.js?v=${VERSION}\"|g" index.html && \
sed -i "s|main\.dart\.js\"|main.dart.js?v=${VERSION}\"|g" flutter_bootstrap.js && \
sed -i "s|main\.dart\.mjs\"|main.dart.mjs?v=${VERSION}\"|g" flutter_bootstrap.js && \
sed -i "s|main\.dart\.wasm\"|main.dart.wasm?v=${VERSION}\"|g" flutter_bootstrap.js
FROM ghcr.io/static-web-server/static-web-server:2 AS sws
FROM scratch
COPY --from=sws /static-web-server /static-web-server
COPY --from=build /app/build/web /public
COPY sws.toml /sws.toml
EXPOSE 8080
USER 65534
ENTRYPOINT ["/static-web-server", "--config-file", "/sws.toml"]
```
**sws.toml** - Required headers for WASM multi-threading:
```toml
[general]
host = "0.0.0.0"
port = 8080
root = "/public"
page-fallback = "/public/index.html"
compression = true
[[advanced.headers]]
source = "**"
[advanced.headers.headers]
Cross-Origin-Opener-Policy = "same-origin"
Cross-Origin-Embedder-Policy = "require-corp"
```
### Android APK
```dockerfile
FROM svrnty/flutter-sdk:android-latest AS build
COPY . /app
WORKDIR /app
RUN flutter pub get && flutter build apk --release
FROM scratch
COPY --from=build /app/build/app/outputs/flutter-apk/app-release.apk /
```
### Linux Desktop
```dockerfile
FROM svrnty/flutter-sdk:linux-latest AS build
WORKDIR /app
COPY . .
RUN flutter pub get && flutter build linux --release
FROM debian:bookworm-slim
RUN apt-get update && apt-get install -y libgtk-3-0 && rm -rf /var/lib/apt/lists/*
COPY --from=build /app/build/linux/arm64/release/bundle /app
ENTRYPOINT ["/app/my_app"]
```
## CI/CD (Gitea Actions)
```yaml
jobs:
build:
runs-on: ubuntu-latest
container:
image: svrnty/flutter-sdk:android-latest
steps:
- uses: actions/checkout@v4
- run: flutter pub get
- run: flutter build apk --release
```
## Tags
- `-latest` - Latest stable Flutter release
- `-` - Specific Flutter version (e.g., `android-3.38.9`)
## Automatic Updates
Images are automatically rebuilt when:
- New Flutter stable versions are released
- Base image security updates are available
Every build is scanned and includes supply chain attestations (SBOM, SLSA provenance).
## License
MIT