diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 07958c87db..3006de8480 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -1,5 +1,7 @@
 name: CI
 on: [push, pull_request]
+env:
+  NODE_VERSION_USED_FOR_DEVELOPMENT: 14
 jobs:
   lint:
     name: Lint source files
@@ -10,6 +12,8 @@ jobs:
 
       - name: Setup Node.js
         uses: actions/setup-node@v1
+        with:
+          node-version: ${{ env.NODE_VERSION_USED_FOR_DEVELOPMENT }}
 
       - name: Cache Node.js modules
         uses: actions/cache@v2
@@ -57,6 +61,8 @@ jobs:
 
       - name: Setup Node.js
         uses: actions/setup-node@v1
+        with:
+          node-version: ${{ env.NODE_VERSION_USED_FOR_DEVELOPMENT }}
 
       - name: Cache Node.js modules
         uses: actions/cache@v2
@@ -81,6 +87,8 @@ jobs:
 
       - name: Setup Node.js
         uses: actions/setup-node@v1
+        with:
+          node-version: ${{ env.NODE_VERSION_USED_FOR_DEVELOPMENT }}
 
       - name: Cache Node.js modules
         uses: actions/cache@v2
@@ -97,25 +105,26 @@ jobs:
         run: npm run testonly:cover
 
       - name: Upload coverage to Codecov
+        if: ${{ always() }}
         uses: codecov/codecov-action@v1
         with:
           file: ./coverage/tests/coverage-final.json
           fail_ci_if_error: true
 
   test:
-    name: Run tests on Node v${{ matrix.node_version }}
+    name: Run tests on Node v${{ matrix.node_version_to_setup }}
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        node_version: [10, 12, 14]
+        node_version_to_setup: [10, 12, 14]
     steps:
       - name: Checkout repo
         uses: actions/checkout@v2
 
-      - name: Setup Node.js v${{ matrix.node_version }}
+      - name: Setup Node.js v${{ matrix.node_version_to_setup }}
         uses: actions/setup-node@v1
         with:
-          node-version: ${{ matrix.node_version }}
+          node-version: ${{ matrix.node_version_to_setup }}
 
       - name: Cache Node.js modules
         uses: actions/cache@v2
@@ -142,6 +151,8 @@ jobs:
 
       - name: Setup Node.js
         uses: actions/setup-node@v1
+        with:
+          node-version: ${{ env.NODE_VERSION_USED_FOR_DEVELOPMENT }}
 
       - name: Cache Node.js modules
         uses: actions/cache@v2
@@ -171,6 +182,8 @@ jobs:
 
       - name: Setup Node.js
         uses: actions/setup-node@v1
+        with:
+          node-version: ${{ env.NODE_VERSION_USED_FOR_DEVELOPMENT }}
 
       - name: Cache Node.js modules
         uses: actions/cache@v2
diff --git a/.nycrc.yml b/.nycrc.yml
index ad74db4ae2..44aaed89e4 100644
--- a/.nycrc.yml
+++ b/.nycrc.yml
@@ -19,3 +19,8 @@ temp-directory: 'coverage/tests'
 report-dir: 'coverage/tests'
 skip-full: true
 reporter: [json, html, text]
+check-coverage: true
+branches: 100
+lines: 100
+functions: 100
+statements: 100
diff --git a/package.json b/package.json
index 05ab923fb1..0582d3ae3f 100644
--- a/package.json
+++ b/package.json
@@ -21,6 +21,9 @@
     "graphql-js"
   ],
   "engines": {
+    "node": ">= 14.2"
+  },
+  "engines_on_npm": {
     "node": ">= 10.x"
   },
   "scripts": {
diff --git a/resources/build.js b/resources/build.js
index 728bef7b88..16ccc0890c 100644
--- a/resources/build.js
+++ b/resources/build.js
@@ -53,6 +53,9 @@ function buildPackageJSON() {
   delete packageJSON.scripts;
   delete packageJSON.devDependencies;
 
+  packageJSON.engines = packageJSON.engines_on_npm;
+  delete packageJSON.engines_on_npm;
+
   const versionJS = require('../dist/version.js');
   assert(
     versionJS.version === packageJSON.version,
diff --git a/resources/utils.js b/resources/utils.js
index e72f9c84d1..85e2f28bfe 100644
--- a/resources/utils.js
+++ b/resources/utils.js
@@ -49,6 +49,13 @@ function rmdirRecursive(dirPath) {
 }
 
 function readdirRecursive(dirPath, opts = {}) {
+  console.log('-------');
+  const result = readdirRecursive2(dirPath, opts);
+  console.log('+++++++');
+  return result;
+}
+
+function readdirRecursive2(dirPath, opts = {}) {
   const { ignoreDir } = opts;
   const result = [];
   for (const dirent of fs.readdirSync(dirPath, { withFileTypes: true })) {
@@ -61,7 +68,7 @@ function readdirRecursive(dirPath, opts = {}) {
     if (ignoreDir && ignoreDir.test(name)) {
       continue;
     }
-    const list = readdirRecursive(path.join(dirPath, name), opts).map((f) =>
+    const list = readdirRecursive2(path.join(dirPath, name), opts).map((f) =>
       path.join(name, f),
     );
     result.push(...list);
diff --git a/src/type/validate.js b/src/type/validate.js
index 4d8e5a8fc2..903ed69951 100644
--- a/src/type/validate.js
+++ b/src/type/validate.js
@@ -357,7 +357,12 @@ function validateTypeImplementsInterface(
         `Interface field ${iface.name}.${fieldName} expects type ` +
           `${inspect(ifaceField.type)} but ${type.name}.${fieldName} ` +
           `is type ${inspect(typeField.type)}.`,
-        [ifaceField.astNode?.type, typeField.astNode?.type],
+        [
+          // istanbul ignore next (TODO need to write coverage tests)
+          ifaceField.astNode?.type,
+          // istanbul ignore next (TODO need to write coverage tests)
+          typeField.astNode?.type,
+        ],
       );
     }
 
@@ -384,7 +389,12 @@ function validateTypeImplementsInterface(
             `expects type ${inspect(ifaceArg.type)} but ` +
             `${type.name}.${fieldName}(${argName}:) is type ` +
             `${inspect(typeArg.type)}.`,
-          [ifaceArg.astNode?.type, typeArg.astNode?.type],
+          [
+            // istanbul ignore next (TODO need to write coverage tests)
+            ifaceArg.astNode?.type,
+            // istanbul ignore next (TODO need to write coverage tests)
+            typeArg.astNode?.type,
+          ],
         );
       }