Support the four most recent major versions of Go

Fixes #963

.github/workflows/ci.yml

@@ -1,12 +1,12 @@
 on:
   push:
-    branches: '**'
+    branches: "**"
     paths-ignore:
-      - 'docs/**'
+      - "docs/**"
   pull_request:
-    branches: '**'
+    branches: "**"
     paths-ignore:
-      - 'docs/**'
+      - "docs/**"
 
 name: Test
 jobs:
@@ -20,23 +20,23 @@ jobs:
 
     strategy:
       matrix:
-        go-version: [1.15.x, 1.16.x, 1.17.x, 1.18.x, 1.19.x, 1.20.x, 1.21.x, 1.22.x, 1.23.x]
+        go-version: [1.20.x, 1.21.x, 1.22.x, 1.23.x]
         os: [ubuntu-latest, windows-latest]
 
     runs-on: ${{ matrix.os }}
 
     steps:
-    - name: Install Go
-      uses: actions/setup-go@v5
-      with:
-        go-version: ${{ matrix.go-version }}
-        check-latest: true
-        cache: false
-    - name: Checkout code
-      uses: actions/checkout@v4
-      with:
-        path: ${{ env.GOPATH }}/src/github.com/${{ github.repository }}
-    - name: Test
-      run: |
-        go get -d -t ./...
-        make test
+      - name: Install Go
+        uses: actions/setup-go@v5
+        with:
+          go-version: ${{ matrix.go-version }}
+          check-latest: true
+          cache: false
+      - name: Checkout code
+        uses: actions/checkout@v4
+        with:
+          path: ${{ env.GOPATH }}/src/github.com/${{ github.repository }}
+      - name: Test
+        run: |
+          go get -d -t ./...
+          make test

go.mod

@@ -1,3 +1,5 @@
 module github.com/go-chi/chi/v5
 
-go 1.14
+// Chi supports the four most recent major versions of Go.
+// See https://github.com/go-chi/chi/issues/963.
+go 1.20