tftsr-devops_investigation/tickets/ci-runner-speed-optimization.md

CI Runner Speed Optimization via Pre-baked Images + Caching

Description

Every CI run (both test.yml and auto-tag.yml) was installing system packages from scratch on each job invocation: apt-get update, Tauri system libs, Node.js via nodesource, and in the arm64 job — a full rustup install. This was the primary cause of slow builds.

The repository already contains pre-baked builder Docker images (.docker/Dockerfile.*) and a build-images.yml workflow to push them to ghcr.io/msicie/. These images were never referenced by the actual CI jobs — a critical gap. This work closes that gap and adds actions/cache@v3 for Cargo and npm.

Acceptance Criteria

• Dockerfile.linux-amd64 includes rustfmt and clippy components
• Dockerfile.linux-arm64 includes rustfmt and clippy components
• test.yml Rust jobs use ghcr.io/msicie/trcaa-linux-amd64:rust1.88-node22
• test.yml Rust jobs have no inline apt-get or rustup component add steps
• test.yml Rust jobs include actions/cache@v3 for ~/.cargo/registry
• test.yml frontend jobs include actions/cache@v3 for ~/.npm
• auto-tag.yml build-linux-amd64 uses pre-baked trcaa-linux-amd64 image
• auto-tag.yml build-windows-amd64 uses pre-baked trcaa-windows-cross image
• auto-tag.yml build-linux-arm64 uses pre-baked trcaa-linux-arm64 image
• All three build jobs have no Install dependencies step
• All three build jobs include actions/cache@v3 for Cargo and npm
• docs/wiki/CICD-Pipeline.md documents pre-baked images, cache keys, and server prerequisites
• build-images.yml triggered manually before merging to ensure images exist in registry

Work Implemented

.docker/Dockerfile.linux-amd64

Added RUN rustup component add rustfmt clippy after the existing target add line. The rust-fmt-check and rust-clippy CI jobs now rely on these being pre-installed in the image rather than installing them at job runtime.

.docker/Dockerfile.linux-arm64

Added && /root/.cargo/bin/rustup component add rustfmt clippy appended to the existing rustup installation RUN command (chained with && to keep it one layer).

.github/workflows/test.yml

• rust-test (fmt + clippy + tests): switched container image from rust:1.88-slim → ghcr.io/msicie/trcaa-linux-amd64:rust1.88-node22. Removed apt-get install git from Checkout steps (git is pre-installed in image). Removed apt-get install libwebkit2gtk-... steps. Removed rustup component add rustfmt and rustup component add clippy steps. Added actions/cache@v3 step for ~/.cargo/registry/index, ~/.cargo/registry/cache, ~/.cargo/git/db keyed on Cargo.lock hash.
• frontend-typecheck, frontend-tests: kept node:22-alpine image (no change needed). Added actions/cache@v3 step for ~/.npm keyed on package-lock.json hash.

.github/workflows/release.yml

• build-linux-amd64: image rust:1.88-slim → ghcr.io/msicie/trcaa-linux-amd64:rust1.88-node22. Removed Checkout apt-get install git, removed entire Install dependencies step. Removed rustup target add x86_64-unknown-linux-gnu from Build step. Added cargo + npm cache.
• build-windows-amd64: image rust:1.88-slim → ghcr.io/msicie/trcaa-windows-cross:rust1.88-node22. Removed Checkout apt-get install git, removed entire Install dependencies step. Removed rustup target add x86_64-pc-windows-gnu from Build step. Added cargo (with -windows- suffix key to avoid collision) + npm cache.
• build-linux-arm64: image ubuntu:22.04 → ghcr.io/msicie/trcaa-linux-arm64:rust1.88-node22. Removed Checkout apt-get install git, removed entire Install dependencies step (~40 lines). Removed . "$HOME/.cargo/env" (PATH already set via ENV in Dockerfile). Removed rustup target add aarch64-unknown-linux-gnu from Build step. Added cargo (with -arm64- suffix key) + npm cache.

docs/wiki/CICD-Pipeline.md

Added two new sections before the Test Pipeline section:

• Pre-baked Builder Images: table of all three images and their contents, rebuild triggers, how-to-rebuild instructions, and the insecure-registries Docker daemon prerequisite for ghcr.io access.
• Cargo and npm Caching: documents the actions/cache@v3 key patterns in use, including the per-platform cache key suffixes for cross-compile jobs. Updated the Test Pipeline section to reference the correct pre-baked image name. Updated the Release Pipeline job table to show which image each build job uses.

Testing Needed

1. Pre-build images (prerequisite): Trigger build-images.yml via Actions → Build CI Docker Images → Run workflow. Confirm all 3 images are pushed and visible at ghcr.io/msicie/.

2. PR test suite: Open a PR with these changes. Verify:

   • rust-test and frontend-test jobs pass
   • Job logs show no apt-get or rustup component add output
   • Cache hit messages appear on second run

3. Release build: Merge to main. Verify release.yml runs and:

   • All build jobs start without Install dependencies step
   • Artifacts are produced and uploaded to the GitHub Release
   • Total release time is significantly reduced (~7 min vs ~25 min before)

4. Expected time savings after caching warms up:

   Job	Before	After
   rust-fmt-check	~2 min	~20 sec
   rust-clippy	~4 min	~45 sec
   rust-tests	~5 min	~1.5 min
   frontend-typecheck	~2 min	~30 sec
   frontend-tests	~3 min	~40 sec
   build-linux-amd64	~10 min	~3 min
   build-windows-amd64	~12 min	~4 min
   build-linux-arm64	~15 min	~4 min
   PR test total (parallel)	~5 min	~1.5 min
   Release total	~25 min	~7 min