diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 96d50bc..588e1fc 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -7,38 +7,27 @@ on:
     branches: [main]
 
 jobs:
-  golangci:
-    name: golangci-lint
+  test:
+    runs-on: ubuntu-latest
     permissions:
       contents: read
       pull-requests: read
-    runs-on: ubuntu-latest
-    timeout-minutes: 5
     steps:
-      - uses: actions/setup-go@v5
-        with:
-          go-version: "1.20"
       - uses: actions/checkout@v4
 
+      - name: Set up Go
+        uses: actions/setup-go@v5
+        with:
+          go-version-file: go.mod
+
       - name: golangci-lint
         uses: golangci/golangci-lint-action@v6
         with:
           version: latest
-          args: --timeout=5m
-
-
-  build:
-    runs-on: ubuntu-latest
-    strategy:
-      matrix:
-        go: ["1.20"]
-    steps:
-      - uses: actions/checkout@v4
-
-      - name: Set up Go
-        uses: actions/setup-go@v5
-        with:
-          go-version: ${{ matrix.go }}
+          args: --timeout=3m
+          skip-cache: true
+          skip-pkg-cache: true
+          skip-build-cache: true
 
       - run: go test -race ./...
       - run: go test -bench=. ./...
diff --git a/go.mod b/go.mod
index 1426d2d..6a14021 100644
--- a/go.mod
+++ b/go.mod
@@ -1,3 +1,3 @@
 module github.com/ringsaturn/go-aqi
 
-go 1.20
+go 1.22
diff --git a/mep/mep_test.go b/mep/mep_test.go
index 454b095..3562cda 100644
--- a/mep/mep_test.go
+++ b/mep/mep_test.go
@@ -173,7 +173,6 @@ func BenchmarkAlgoCalc(b *testing.B) {
 
 var (
 	largeData [][]*goaqi.Var
-	lessData  [][]*goaqi.Var
 )
 
 func init() {