build: add CI workflow and fix flaky compaction test

.github/workflows/ci.yml

@@ -0,0 +1,28 @@
+name: CI
+
+on:
+  push:
+    branches: [main]
+  pull_request:
+
+permissions:
+  contents: read
+
+concurrency:
+  group: ci-${{ github.ref }}
+  cancel-in-progress: true
+
+jobs:
+  build-test:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-go@v5
+        with:
+          go-version: "1.26.4"
+          cache: true
+      - run: go build ./...
+      - run: go vet ./...
+      - run: go test ./... -count=1 -race -coverprofile=coverage.out
+      - name: Coverage summary
+        run: go tool cover -func=coverage.out | tail -1

internal/memory/durability_test.go

@@ -259,10 +259,13 @@ func TestCompactionDuringConcurrentUse(t *testing.T) {
 	s := open(t, Options{JournalPath: path, CompactAfter: 20})
 	const workers, rounds = 8, 120
 	var wg sync.WaitGroup
+	var compactWG sync.WaitGroup
 	var mu sync.Mutex
 	kept := 0
 	stop := make(chan struct{})
+	compactWG.Add(1)
 	go func() {
+		defer compactWG.Done()
 		for {
 			select {
 			case <-stop:
@@ -314,6 +317,7 @@ func TestCompactionDuringConcurrentUse(t *testing.T) {
 	}
 	wg.Wait()
 	close(stop)
+	compactWG.Wait() // join the compactor before Close so it cannot call Compact on a closed store
 	st := s.Stats()
 	if st.Memories != kept || st.Updates != workers*rounds || st.JournalErrors != 0 {
 		t.Fatalf("stats = %+v, want %d memories and %d updates", st, kept, workers*rounds)