Add standard Workflow section to TODO.md

## Summary

Rewrites the Dockerfile to use sha256-pinned images and proper multi-stage build structure. Adds missing Makefile targets and a Gitea CI workflow.

## Changes

### Dockerfile
- **Lint stage**: `golangci/golangci-lint` v1.64.8 pinned by sha256 — runs `make fmt-check` + `make lint`
- **Test stage**: `golang` 1.22.12 pinned by sha256 — runs `make test` with dependency on lint stage
- Removed redundant final stage (this is a library with no binary to build)
- Both images pinned by digest with version+date comments

### Makefile
- Added `fmt-check` target: verifies `gofmt` compliance without modifying files
- Added `check` target: runs `fmt-check`, `lint`, `test` in sequence
- Added `hooks` target: installs a pre-commit hook that runs `make check`
- Separated `gofmt` check from `lint` target (was previously bundled)
- Changed default target from `test` to `check`

### CI
- Added `.gitea/workflows/check.yml`: runs `docker build .` on push to main and on PRs

## Verification

`docker build --progress plain .` passes — all stages complete successfully.

closes #9

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Co-authored-by: clawbot <clawbot@noreply.git.eeqj.de>
Reviewed-on: #14
Co-authored-by: clawbot <clawbot@noreply.example.org>
Co-committed-by: clawbot <clawbot@noreply.example.org>

.gitea/workflows/check.yml

@@ -0,0 +1,12 @@
+name: check
+
+on:
+  push:
+  pull_request:
+
+jobs:
+  check:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
+      - run: docker build .

Dockerfile

@@ -1,39 +1,20 @@
-# First stage: Use the golangci-lint image to run the linter
-FROM golangci/golangci-lint:latest as lint
-
-# Set the Current Working Directory inside the container
-WORKDIR /app
-
-# Copy the go.mod file and the rest of the application code
-COPY go.mod ./
+# Lint stage: format check + golangci-lint
+# golangci-lint v1.64.8 (2025-02-18)
+FROM golangci/golangci-lint@sha256:2987913e27f4eca9c8a39129d2c7bc1e74fbcf77f181e01cea607be437aa5cb8 AS lint
+WORKDIR /src
+COPY go.mod go.sum ./
+RUN go mod download
 COPY . .
+RUN make fmt-check
+RUN make lint
 
-# Run golangci-lint
-RUN golangci-lint run
-
-RUN sh -c 'test -z "$(gofmt -l .)"'
-
-# Second stage: Use the official Golang image to run tests
-FROM golang:1.22 as test
-
-# Set the Current Working Directory inside the container
-WORKDIR /app
-
-# Copy the go.mod file and the rest of the application code
-COPY go.mod ./
+# Test stage: run full test suite
+# golang 1.22.12 (2025-02-04)
+FROM golang@sha256:1cf6c45ba39db9fd6db16922041d074a63c935556a05c5ccb62d181034df7f02 AS test
+# Depend on lint stage so both stages always run
+COPY --from=lint /src/go.sum /dev/null
+WORKDIR /src
+COPY go.mod go.sum ./
+RUN go mod download
 COPY . .
-
-# Run tests
-RUN go test -v ./...
-
-# Final stage: Combine the linting and testing stages
-FROM golang:1.22 as final
-
-# Ensure that the linting stage succeeded
-WORKDIR /app
-COPY --from=lint /app .
-COPY --from=test /app .
-
-# Set the final CMD to something minimal since we only needed to verify lint and tests during build
-CMD ["echo", "Build and tests passed successfully!"]
-
+RUN make test

Makefile

@@ -1,6 +1,6 @@
-.PHONY: test
+.PHONY: test fmt fmt-check lint check docker hooks
 
-default: test
+default: check
 
 test:
 	@go test -v ./...
@@ -9,9 +9,20 @@ fmt:
 	goimports -l -w .
 	golangci-lint run --fix
 
+fmt-check:
+	@test -z "$$(gofmt -l .)" || { echo "gofmt would reformat:"; gofmt -l .; exit 1; }
+
 lint:
 	golangci-lint run
-	sh -c 'test -z "$$(gofmt -l .)"'
+
+check: fmt-check lint test
 
 docker:
 	docker build --progress plain .
+
+hooks:
+	@echo "Installing git hooks..."
+	@mkdir -p .git/hooks
+	@printf '#!/bin/sh\nmake check\n' > .git/hooks/pre-commit
+	@chmod +x .git/hooks/pre-commit
+	@echo "Pre-commit hook installed."

TODO.md

@@ -0,0 +1,53 @@
+# Workflow
+
+* branch (from `main`)
+* do the work in Next Step
+* move Next Step to the top of Completed Steps
+* move the top item of Future Steps into Next Step
+* commit (`TODO.md` changes in the same commit as the work)
+* merge to `main` if the branch is not protected, otherwise open a PR
+* push
+
+# Status
+
+1.0+
+
+Tagged v1.0.0 (2024-06-14) and 1.0.1 (2026-02-08). In post-1.0
+maintenance; the library is referenced by the Go styleguide.
+
+# Next Step
+
+Bring the Makefile up to policy in one commit: add fmt-check, check, and
+hooks targets (test/lint/fmt/docker exist) and add the missing policy
+files it depends on: .golangci.yml, REPO_POLICIES.md, .editorconfig,
+.dockerignore, and .gitea/workflows/check.yml running make check.
+
+# Completed Steps
+
+* 2026-02-08: fixed JSONHandler deadlock from recursive log.Println,
+    with regression test; tagged 1.0.1
+* 2024-06-14: 1.0 prep: lint and fmt enforced in Docker build, call
+    stack depth fix so log locations report correctly, example script,
+    removed non-building RELP code; tagged v1.0.0
+* 2024-05-22: module path moved to sneak.berlin/go/simplelog
+* 2024-05-14: initial library: slog-based console, JSON, webhook, and
+    RELP handlers, MultiplexHandler, caller file/line info, UTC ISO
+    timestamps, level-colored output
+
+# Future Steps
+
+* Rewrite the Dockerfile to run make check with sha256-pinned base
+    images (currently golangci/golangci-lint:latest and golang:1.22,
+    unpinned, duplicating Makefile logic instead of calling it)
+* Restructure README.md into the standard sections: Description,
+    Getting Started, Rationale, Design, TODO, License, Author
+* Delete the old plain TODO file once this TODO.md lands
+* Add .aider.* to .gitignore and remove the stray aider artifacts from
+    the working tree
+* Pick one tag scheme before the next release (v1.0.0 vs 1.0.1 are
+    inconsistent)
+* Fix RELP output to cache (from old TODO)
+* Re-add RELP delivery over TCP to remote rsyslog imrelp; removed
+    2024-06-14 because it did not build (README planned feature)
+* Add regex filtering for webhook logs (from old TODO)
+* Better console output format (from old TODO)