diff --git a/.eslintrc.yml b/.eslintrc.yml
index eb1850f..abcafd7 100644
--- a/.eslintrc.yml
+++ b/.eslintrc.yml
@@ -1,13 +1,15 @@
 root: true
 
 extends:
-  - plugin:@mysticatea/es2015
-  - plugin:@mysticatea/+modules
-  - plugin:@mysticatea/+node
+- plugin:@mysticatea/es2015
 
-rules:
-  init-declarations: "off"
-  "@mysticatea/node/no-unsupported-features/es-syntax":
+overrides:
+- files:
+  - src/**/*.js
+  - test/**/*.js
+  extends: plugin:@mysticatea/+modules
+  rules:
+    init-declarations: "off"
+    "@mysticatea/node/no-unsupported-features/es-syntax":
     - error
-    - ignores:
-      - modules
+    - ignores: [modules]
diff --git a/docs/.vuepress/config.js b/docs/.vuepress/config.js
index f33f588..edc74c0 100644
--- a/docs/.vuepress/config.js
+++ b/docs/.vuepress/config.js
@@ -1,3 +1,5 @@
+"use strict"
+
 module.exports = {
     title: "eslint-utils",
     description: "Utilities for ESLint plugins and custom rules.",
diff --git a/docs/.vuepress/override.styl b/docs/.vuepress/palette.styl
similarity index 100%
rename from docs/.vuepress/override.styl
rename to docs/.vuepress/palette.styl
diff --git a/package.json b/package.json
index e92523c..39e64df 100644
--- a/package.json
+++ b/package.json
@@ -12,23 +12,23 @@
     "index.*"
   ],
   "dependencies": {
-    "eslint-visitor-keys": "^1.0.0"
+    "eslint-visitor-keys": "^1.1.0"
   },
   "devDependencies": {
-    "@mysticatea/eslint-plugin": "^10.0.3",
-    "codecov": "^3.0.2",
+    "@mysticatea/eslint-plugin": "^12.0.0",
+    "codecov": "^3.6.1",
     "dot-prop": "^4.2.0",
-    "eslint": "^5.16.0",
-    "esm": "^3.0.55",
-    "espree": "^5.0.1",
-    "mocha": "^5.2.0",
+    "eslint": "^6.5.1",
+    "esm": "^3.2.25",
+    "espree": "^6.1.1",
+    "mocha": "^6.2.2",
     "npm-run-all": "^4.1.5",
-    "nyc": "^13.0.1",
-    "opener": "^1.4.3",
-    "rimraf": "^2.6.2",
-    "rollup": "^1.16.7",
+    "nyc": "^14.1.1",
+    "opener": "^1.5.1",
+    "rimraf": "^3.0.0",
+    "rollup": "^1.25.0",
     "rollup-plugin-sourcemaps": "^0.4.2",
-    "vuepress": "^0.14.4",
+    "vuepress": "^1.2.0",
     "warun": "^1.0.0"
   },
   "scripts": {
diff --git a/src/get-static-value.js b/src/get-static-value.js
index 0848083..173c01a 100644
--- a/src/get-static-value.js
+++ b/src/get-static-value.js
@@ -1,7 +1,18 @@
-/* globals BigInt */
+/* globals BigInt, globalThis, global, self, window */
 
 import { findVariable } from "./find-variable"
 
+const globalObject =
+    typeof globalThis !== "undefined"
+        ? globalThis
+        : typeof self !== "undefined"
+        ? self
+        : typeof window !== "undefined"
+        ? window
+        : typeof global !== "undefined"
+        ? global
+        : {}
+
 const builtinNames = Object.freeze(
     new Set([
         "Array",
@@ -76,13 +87,13 @@ const callAllowed = new Set(
         Number.parseFloat,
         Number.parseInt,
         Object,
-        Object.entries, //eslint-disable-line @mysticatea/node/no-unsupported-features/es-builtins
+        Object.entries,
         Object.is,
         Object.isExtensible,
         Object.isFrozen,
         Object.isSealed,
         Object.keys,
-        Object.values, //eslint-disable-line @mysticatea/node/no-unsupported-features/es-builtins
+        Object.values,
         parseFloat,
         parseInt,
         RegExp,
@@ -294,9 +305,9 @@ const operations = Object.freeze({
                 variable != null &&
                 variable.defs.length === 0 &&
                 builtinNames.has(variable.name) &&
-                variable.name in global
+                variable.name in globalObject
             ) {
-                return { value: global[variable.name] }
+                return { value: globalObject[variable.name] }
             }
 
             // Constants.
diff --git a/src/reference-tracker.js b/src/reference-tracker.js
index e1fc8cd..f63c2bd 100644
--- a/src/reference-tracker.js
+++ b/src/reference-tracker.js
@@ -162,11 +162,11 @@ export class ReferenceTracker {
                         esm
                             ? nextTraceMap
                             : this.mode === "legacy"
-                                ? Object.assign(
-                                      { default: nextTraceMap },
-                                      nextTraceMap
-                                  )
-                                : { default: nextTraceMap }
+                            ? Object.assign(
+                                  { default: nextTraceMap },
+                                  nextTraceMap
+                              )
+                            : { default: nextTraceMap }
                     )
 
                     if (esm) {
diff --git a/test/pattern-matcher.js b/test/pattern-matcher.js
index c14fd3b..717867f 100644
--- a/test/pattern-matcher.js
+++ b/test/pattern-matcher.js
@@ -3,7 +3,7 @@ import { PatternMatcher } from "../src/"
 
 const NAMED_CAPTURE_GROUP_SUPPORTED = (() => {
     try {
-        new RegExp("(?<a>)", "u") //eslint-disable-line no-new, @mysticatea/node/no-unsupported-features/es-syntax
+        new RegExp("(?<a>)", "u") //eslint-disable-line no-new, prefer-regex-literals, @mysticatea/node/no-unsupported-features/es-syntax
         return true
     } catch (_error) {
         return false