comicrime · Aug 29, 2026 · Aug 29, 2026 · Aug 29, 2026
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
@@ -6,6 +6,10 @@ on:
     # there does not need a second one
     branches-ignore: [master]
   workflow_call:
+    outputs:
+      modules:
+        description: Every module directory in the repo
+        value: ${{ jobs.modules.outputs.all }}
 
 # A branch that is pushed again supersedes its own in-flight run, but master is left
 # alone: its run gates the release.
@@ -16,49 +20,97 @@ concurrency:
 permissions:
   contents: read
 
+# Each module is built and tested the way a consumer gets it - resolved from its own
+# go.mod - rather than through the workspace, which would paper over a missing require.
+env:
+  GOWORK: "off"
+
 jobs:
+  # Modules are discovered rather than listed, so adding one to the repo puts it under
+  # CI without touching this file.
+  modules:
+    runs-on: ubuntu-latest
+    outputs:
+      all: ${{ steps.find.outputs.all }}
+    steps:
+      - uses: actions/checkout@v7
+
+      - name: Find the modules
+        id: find
+        run: |
+          set -euo pipefail
+
+          all=$(find . -name go.mod -not -path './.git/*' -printf '%h\n' \
+            | sed 's|^\./||' \
+            | sort \
+            | jq -R -s -c 'split("\n") | map(select(length > 0))')
+
+          echo "all=$all" >> "$GITHUB_OUTPUT"
+          echo "Modules: $all"
+
   lint:
+    needs: modules
     runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        module: ${{ fromJSON(needs.modules.outputs.all) }}
     steps:
       - uses: actions/checkout@v7
 
       - uses: actions/setup-go@v7
         with:
-          go-version-file: go.mod
+          go-version-file: ${{ matrix.module }}/go.mod
 
-      - name: Tool versions
+      - name: Tool version
         id: tools
-        run: |
-          echo "golangci=$(make -s print-GOLANGCI_VERSION)" >> "$GITHUB_OUTPUT"
-          echo "actionlint=$(make -s print-ACTIONLINT_VERSION)" >> "$GITHUB_OUTPUT"
+        run: echo "golangci=$(make -s print-GOLANGCI_VERSION)" >> "$GITHUB_OUTPUT"
 
+      # the root .golangci.yml applies to every module: golangci-lint walks up for it
       - uses: golangci/golangci-lint-action@v9
         with:
           version: ${{ steps.tools.outputs.golangci }}
-
-      # the other half of `make lint`, so CI is never weaker than the local target
-      - name: Lint the workflows
-        env:
-          ACTIONLINT_VERSION: ${{ steps.tools.outputs.actionlint }}
-        run: |
-          go install "github.com/rhysd/actionlint/cmd/actionlint@${ACTIONLINT_VERSION}"
-          "$(go env GOPATH)/bin/actionlint"
+          working-directory: ${{ matrix.module }}
 
       - name: go.mod and go.sum are tidy
+        working-directory: ${{ matrix.module }}
         run: |
           go mod tidy
           git diff --exit-code go.mod go.sum
 
+  # One repo, one set of workflows - not per module.
+  workflows:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v7
+
+      - uses: actions/setup-go@v7
+        with:
+          go-version-file: caller/go.mod
+
+      - name: Lint the workflows
+        run: |
+          set -euo pipefail
+          go install "github.com/rhysd/actionlint/cmd/actionlint@$(make -s print-ACTIONLINT_VERSION)"
+          "$(go env GOPATH)/bin/actionlint"
+
   test:
+    needs: modules
     runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        module: ${{ fromJSON(needs.modules.outputs.all) }}
     steps:
       - uses: actions/checkout@v7
 
       - uses: actions/setup-go@v7
         with:
-          go-version-file: go.mod
+          go-version-file: ${{ matrix.module }}/go.mod
 
       - run: go build ./...
+        working-directory: ${{ matrix.module }}
 
       # -race because the resolver cache and the registry heartbeat are concurrent
       - run: go test -race -count=1 ./...
+        working-directory: ${{ matrix.module }}
diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
@@ -5,7 +5,7 @@ on:
     branches: [master]
 
 # Releases are serialised, never cancelled: two merges landing together must each get
-# their turn at the tag rather than one clobbering the other's run.
+# their turn at the tags rather than one clobbering the other's run.
 concurrency:
   group: release
   cancel-in-progress: false
@@ -26,43 +26,68 @@ jobs:
     steps:
       - uses: actions/checkout@v7
         with:
-          fetch-depth: 0  # the whole tag history, to find the version to bump
+          fetch-depth: 0  # the whole tag history, to find each module's version to bump
 
-      - name: Work out the next version
-        id: version
-        run: |
-          set -euo pipefail
-
-          # A re-run of this workflow, or a commit tagged by hand, must not publish a
-          # second version of the same code.
-          if tag=$(git describe --exact-match --tags HEAD 2>/dev/null); then
-            echo "HEAD is already released as $tag, nothing to do"
-            exit 0
-          fi
-
-          latest=$(git tag -l 'v*' --sort=-v:refname | grep -E '^v[0-9]+\.[0-9]+\.[0-9]+$' | head -1 || true)
-          if [ -z "$latest" ]; then
-            next=v0.1.0
-          else
-            IFS=. read -r major minor patch <<<"${latest#v}"
-            next="v${major}.${minor}.$((patch + 1))"
-          fi
-
-          echo "next=$next" >> "$GITHUB_OUTPUT"
-          echo "Releasing $next (previous: ${latest:-none})"
+      - uses: actions/setup-go@v7
+        with:
+          go-version-file: caller/go.mod
 
-      - name: Tag and release
-        if: steps.version.outputs.next != ''
+      # Every module is versioned on its own, so a change to one does not drag the
+      # others through a release they have no new code for. Tags carry the module's
+      # directory as a prefix, which is how the go command resolves a nested module.
+      - name: Tag the modules whose files changed
         env:
           GH_TOKEN: ${{ github.token }}
-          NEXT: ${{ steps.version.outputs.next }}
+          MODULES: ${{ needs.ci.outputs.modules }}
         run: |
           set -euo pipefail
 
           git config user.name "github-actions[bot]"
           git config user.email "41898282+github-actions[bot]@users.noreply.github.com"
 
-          git tag -a "$NEXT" -m "$NEXT"
-          git push origin "$NEXT"
+          tagged=()
+          while read -r dir; do
+            # a module that replaces another by local path cannot be consumed from
+            # outside the repo, so it is built and tested but never published
+            replaces=$(go mod edit -json "$dir/go.mod" \
+              | jq '[.Replace // [] | .[] | select(.New.Path | test("^\\.{1,2}/"))] | length')
+            if [ "$replaces" -ne 0 ]; then
+              echo "$dir: not publishable (replaces a module by local path), skipping"
+              continue
+            fi
+
+            # A re-run of this workflow, or a tag pushed by hand, must not publish a
+            # second version of the same code.
+            existing=$(git tag --points-at HEAD --list "$dir/v*" | head -1)
+            if [ -n "$existing" ]; then
+              echo "$dir: HEAD is already released as $existing, skipping"
+              continue
+            fi
+
+            latest=$(git tag --list "$dir/v*" --sort=-v:refname \
+              | grep -E "^$dir/v[0-9]+\.[0-9]+\.[0-9]+$" | head -1 || true)
+
+            if [ -z "$latest" ]; then
+              next="$dir/v0.1.0"
+            elif git diff --quiet "$latest" HEAD -- "$dir"; then
+              echo "$dir: unchanged since $latest, skipping"
+              continue
+            else
+              IFS=. read -r major minor patch <<<"${latest#"$dir/v"}"
+              next="$dir/v${major}.${minor}.$((patch + 1))"
+            fi
+
+            echo "$dir: releasing $next (previous: ${latest:-none})"
+            git tag -a "$next" -m "$next"
+            tagged+=("$next")
+          done < <(jq -r '.[]' <<<"$MODULES")
+
+          if [ ${#tagged[@]} -eq 0 ]; then
+            echo "No module changed, nothing to release"
+            exit 0
+          fi
 
-          gh release create "$NEXT" --title "$NEXT" --generate-notes
+          git push origin "${tagged[@]}"
+          for tag in "${tagged[@]}"; do
+            gh release create "$tag" --title "$tag" --generate-notes
+          done
diff --git a/.gitignore b/.gitignore
@@ -0,0 +1 @@
+go.work.sum
diff --git a/Makefile b/Makefile
@@ -3,13 +3,24 @@ ACTIONLINT_VERSION ?= v1.7.12
 
 GOBIN ?= $(or $(shell go env GOBIN),$(shell go env GOPATH)/bin)
 
+# Discovered rather than listed, so a new module is covered without editing this file.
+MODULES := $(patsubst ./%/go.mod,%,$(shell find . -name go.mod -not -path './.git/*' | sort))
+
+# GOWORK=off so each module is exercised the way a consumer gets it, resolved from its
+# own go.mod rather than through the workspace.
 .PHONY: test lint install-tools
 
-test: 
-	go test -v ./...
+test:
+	@for m in $(MODULES); do \
+		echo "== $$m"; \
+		(cd $$m && GOWORK=off go test -v ./...) || exit 1; \
+	done
 
 lint:
-	$(GOBIN)/golangci-lint run ./...
+	@for m in $(MODULES); do \
+		echo "== $$m"; \
+		(cd $$m && GOWORK=off $(GOBIN)/golangci-lint run ./...) || exit 1; \
+	done
 	$(GOBIN)/actionlint
 
 install-tools:

diff --git a/README.md b/README.md
@@ -1 +1,17 @@
-# Callpack
+# Callpack
+
+Modules that I constantly implement in my projects: and which I decided to collect in one place for easy reuse! 
+
+| Module | Import path | What it does |
+| --- | --- | --- |
+| `caller` | `github.com/draincloud/callpack/caller` | `http.Client` fancy wrapper with a round-tripper middleware chain: headers, logging, etc |
+| `registry` | `github.com/draincloud/callpack/registry` | Registers a service instance in consul and heartbeats its TTL check. |
+
+```sh
+go get github.com/draincloud/callpack/caller
+go get github.com/draincloud/callpack/registry
+```
+
+Each is tagged with its own prefix — `caller/v0.1.0`, `registry/v0.1.0`
+
+`integration/` holds the tests that exercise the two against each other. 
diff --git a/caller/go.mod b/caller/go.mod
@@ -0,0 +1,29 @@
+module github.com/draincloud/callpack/caller
+
+go 1.25.0
+
+require (
+	github.com/draincloud/logger v0.0.4
+	github.com/hashicorp/consul/api v1.32.1
+	github.com/stretchr/testify v1.12.1
+)
+
+require (
+	github.com/armon/go-metrics v0.4.1 // indirect
+	github.com/fatih/color v1.18.0 // indirect
+	github.com/hashicorp/errwrap v1.1.0 // indirect
+	github.com/hashicorp/go-cleanhttp v0.5.2 // indirect
+	github.com/hashicorp/go-hclog v1.5.0 // indirect
+	github.com/hashicorp/go-immutable-radix v1.3.1 // indirect
+	github.com/hashicorp/go-multierror v1.1.1 // indirect
+	github.com/hashicorp/go-rootcerts v1.0.2 // indirect
+	github.com/hashicorp/golang-lru v0.5.4 // indirect
+	github.com/hashicorp/serf v0.10.1 // indirect
+	github.com/mattn/go-colorable v0.1.13 // indirect
+	github.com/mattn/go-isatty v0.0.20 // indirect
+	github.com/mitchellh/go-homedir v1.1.0 // indirect
+	github.com/mitchellh/mapstructure v1.5.0 // indirect
+	go.yaml.in/yaml/v3 v3.0.5 // indirect
+	golang.org/x/exp v0.0.0-20250305212735-054e65f0b394 // indirect
+	golang.org/x/sys v0.31.0 // indirect
+)