diff --git a/lib/cli.js b/lib/cli.js
index e89ecc19..19664d5d 100755
--- a/lib/cli.js
+++ b/lib/cli.js
@@ -36,7 +36,7 @@ exports.run = async function () {
     settings.lintingPath = process.cwd();
 
     if (settings.coverage) {
-        Modules.coverage.instrument(settings);
+        await Modules.coverage.instrument(settings);
     }
     else if (settings.transform) {
         Modules.transform.install(settings);
diff --git a/lib/index.js b/lib/index.js
index 7cf3875e..a8ea4fdd 100755
--- a/lib/index.js
+++ b/lib/index.js
@@ -21,7 +21,6 @@ for (const module of ['coverage', 'leaks', 'types']) {
     Object.defineProperty(exports, module, Object.getOwnPropertyDescriptor(Modules, module));
 }
 
-
 /*
     experiment('Utilities', () => {
 
diff --git a/lib/linter/index.js b/lib/linter/index.js
index b4c156e9..0c476d53 100755
--- a/lib/linter/index.js
+++ b/lib/linter/index.js
@@ -10,7 +10,7 @@ const Hoek = require('@hapi/hoek');
 const internals = {};
 
 
-exports.lint = function () {
+exports.lint = async function () {
 
     const configuration = {
         ignore: true
@@ -24,7 +24,7 @@ exports.lint = function () {
         !Fs.existsSync('.eslintrc.yml') &&
         !Fs.existsSync('.eslintrc.json') &&
         !Fs.existsSync('.eslintrc')) {
-        configuration.configFile = Path.join(__dirname, '.eslintrc.js');
+        configuration.overrideConfigFile = Path.join(__dirname, '.eslintrc.js');
     }
 
     if (options) {
@@ -33,17 +33,14 @@ exports.lint = function () {
 
     let results;
     try {
-        const engine = new Eslint.CLIEngine(configuration);
-        results = engine.executeOnFiles(['.']);
+        const eslint = new Eslint.ESLint(configuration);
+        results = await eslint.lintFiles(['.']);
     }
     catch (ex) {
-        results = {
-            results: [{ messages: [ex] }]
-        };
+        results = [{ messages: [ex] }];
     }
 
-
-    return results.results.map((result) => {
+    return results.map((result) => {
 
         const transformed = {
             filename: result.filePath
@@ -68,4 +65,10 @@ exports.lint = function () {
     });
 };
 
-process.send(exports.lint());
+const main = async () =>  {
+
+    const results = await exports.lint();
+    process.send(results);
+};
+
+main();
diff --git a/lib/modules/coverage.js b/lib/modules/coverage.js
index b42c61d2..ab2da633 100755
--- a/lib/modules/coverage.js
+++ b/lib/modules/coverage.js
@@ -18,7 +18,7 @@ const Transform = require('./transform');
 const internals = {
     ext: Symbol.for('@hapi/lab/coverage/initialize'),
     _state: Symbol.for('@hapi/lab/coverage/_state'),
-    EslintEngine: new ESLint.CLIEngine({ baseConfig: Eslintrc })
+    eslint: new ESLint.ESLint({ baseConfig: Eslintrc })
 };
 
 
@@ -69,7 +69,7 @@ if (typeof global.__$$labCov === 'undefined') {
 // $lab:coverage:on$
 
 
-exports.instrument = function (options) {
+exports.instrument = async function (options) {
 
     if (options['coverage-module']) {
         for (const name of options['coverage-module']) {
@@ -77,8 +77,10 @@ exports.instrument = function (options) {
         }
     }
 
+    const ctx = await internals.context(options);
+
     internals.state.patterns.unshift(internals.pattern(options));
-    Transform.install(options, internals.prime);
+    Transform.install(options, (ext) => internals.prime(ext, ctx));
 };
 
 
@@ -114,7 +116,7 @@ internals.escape = function (string) {
 };
 
 
-internals.prime = function (extension) {
+internals.prime = function (extension, ctx) {
 
     require.extensions[extension] = function (localModule, filename) {
 
@@ -122,7 +124,7 @@ internals.prime = function (extension) {
         if (Path.basename(filename, extension) !== '.eslintrc') {
             for (let i = 0; i < internals.state.patterns.length; ++i) {
                 if (internals.state.patterns[i].test(filename.replace(/\\/g, '/'))) {
-                    return localModule._compile(internals.instrument(filename), filename);
+                    return localModule._compile(internals.instrument(filename, ctx), filename);
                 }
             }
         }
@@ -133,7 +135,7 @@ internals.prime = function (extension) {
 };
 
 
-internals.instrument = function (filename) {
+internals.instrument = function (filename, ctx) {
 
     filename = filename.replace(/\\/g, '/');
 
@@ -331,9 +333,8 @@ internals.instrument = function (filename) {
 
     // Parse tree
 
-    const eslintConfig = internals.EslintEngine.getConfigForFile(filename);
     const tree = ESLintParser.parse(content, {
-        ...eslintConfig.parserOptions,
+        ...ctx.parserOptions,
         loc: true,
         range: true,
         comment: true
@@ -520,6 +521,7 @@ exports.analyze = async function (options) {
 
     const report = internals.state.files;
     const pattern = internals.pattern(options);
+    const ctx = await internals.context(options);
 
     const cov = {
         sloc: 0,
@@ -537,7 +539,7 @@ exports.analyze = async function (options) {
         const filename = file.replace(/\\/g, '/');
         if (pattern.test(filename)) {
             if (!report[filename]) {
-                internals.instrument(filename);
+                internals.instrument(filename, ctx);
             }
 
             report[filename].source = internals.state.sources[filename] || [];
@@ -778,3 +780,14 @@ internals.external = function (filename) {
 
     return reports.length ? reports : null;
 };
+
+internals.context = async (options) => {
+
+    // The parserOptions are shared by all files for coverage purposes, based on
+    // the effective eslint config for a hypothetical file {coveragePath}/x.js
+    const { parserOptions } = await internals.eslint.calculateConfigForFile(
+        Path.join(options.coveragePath || '', 'x.js')
+    );
+
+    return { parserOptions };
+};
diff --git a/lib/modules/typescript.js b/lib/modules/typescript.js
index 37497495..364be6f4 100755
--- a/lib/modules/typescript.js
+++ b/lib/modules/typescript.js
@@ -13,14 +13,15 @@ internals.transform = function (content, fileName) {
     if (!internals.configs.has(configFile)) {
         try {
             var { config, error } = Typescript.readConfigFile(configFile, Typescript.sys.readFile);
-            if (error) {
-                throw new Error(`TypeScript config error in ${configFile}: ${error.messageText}`);
-            }
         }
         catch (err) {
             throw new Error(`Cannot find a tsconfig file for ${fileName}`);
         }
 
+        if (error) {
+            throw new Error(`TypeScript config error in ${configFile}: ${error.messageText}`);
+        }
+
         const { options } = Typescript.parseJsonConfigFileContent(config, Typescript.sys, Typescript.getDirectoryPath(configFile), {}, configFile);
         options.sourceMap = false;
         options.inlineSourceMap = true;
diff --git a/package.json b/package.json
index 2731733f..27918ba5 100755
--- a/package.json
+++ b/package.json
@@ -19,13 +19,13 @@
         ]
     },
     "dependencies": {
-        "@babel/core": "^7.14.3",
-        "@babel/eslint-parser": "^7.14.3",
+        "@babel/core": "^7.16.0",
+        "@babel/eslint-parser": "^7.16.0",
         "@hapi/bossy": "5.x.x",
         "@hapi/eslint-plugin": "^5.1.0",
         "@hapi/hoek": "9.x.x",
         "diff": "^5.0.0",
-        "eslint": "7.x.x",
+        "eslint": "8.x.x",
         "find-rc": "4.x.x",
         "globby": "10.x.x",
         "handlebars": "4.x.x",
diff --git a/test/coverage.js b/test/coverage.js
index e63b142d..c0a88e77 100755
--- a/test/coverage.js
+++ b/test/coverage.js
@@ -29,6 +29,7 @@ const internals = {
 
 
 const lab = exports.lab = _Lab.script();
+const before = lab.before;
 const describe = lab.describe;
 const it = lab.it;
 const expect = Code.expect;
@@ -36,7 +37,10 @@ const expect = Code.expect;
 
 describe('Coverage', () => {
 
-    Lab.coverage.instrument({ coveragePath: Path.join(__dirname, 'coverage'), coverageExclude: 'exclude' });
+    before({}, async () => {
+
+        await Lab.coverage.instrument({ coveragePath: Path.join(__dirname, 'coverage'), coverageExclude: 'exclude' });
+    });
 
     it('computes sloc without comments', async () => {
 
@@ -132,7 +136,7 @@ describe('Coverage', () => {
         expect(cov.percent).to.equal(100);
     });
 
-    it('logs to stderr when coverageExclude file has fs.stat issue', async () => {
+    it('logs to stderr when coverageExclude file has fs.stat issue', async (flags) => {
 
         const Test = require('./coverage/test-folder/test-name.js');
 
@@ -141,8 +145,15 @@ describe('Coverage', () => {
         const origStatSync = Fs.statSync;
         const origErrorLog = console.error;
 
+        let calls = 0;
         Fs.statSync = () => {
 
+            calls++;
+            if (calls === 3) {
+                // Only mock for first 3 calls
+                Fs.statSync = origStatSync;
+            }
+
             const err = new Error();
             err.code = 'BOOM';
             throw err;
@@ -153,9 +164,13 @@ describe('Coverage', () => {
             expect(data.code).to.equal('BOOM');
         };
 
+        flags.onCleanup = () => {
+
+            Fs.statSync = origStatSync;
+            console.error = origErrorLog;
+        };
+
         const cov = await Lab.coverage.analyze({ coveragePath: Path.join(__dirname, 'coverage/test-folder'), coverageExclude: ['test', 'node_modules', 'test-name.js'] });
-        Fs.statSync = origStatSync;
-        console.error = origErrorLog;
         expect(cov.percent).to.equal(100);
     });
 
@@ -577,7 +592,7 @@ describe('Coverage', () => {
         it('reports external coverage', async () => {
 
             const coveragePath = Path.join(__dirname, 'coverage/module');
-            Lab.coverage.instrument({ coveragePath, 'coverage-module': ['@hapi/lab-external-module-test'] });
+            await Lab.coverage.instrument({ coveragePath, 'coverage-module': ['@hapi/lab-external-module-test'] });
 
             require(coveragePath);
 
@@ -615,12 +630,12 @@ describe('Coverage', () => {
 
 describe('Coverage via Transform API', () => {
 
-    lab.before(() => {
+    lab.before(async () => {
 
         internals.js = require.extensions['.js'];
         internals.inl = require.extensions['.inl'];
 
-        Lab.coverage.instrument({ coveragePath: Path.join(__dirname, 'coverage'), coverageExclude: 'exclude', transform: internals.transform });
+        await Lab.coverage.instrument({ coveragePath: Path.join(__dirname, 'coverage'), coverageExclude: 'exclude', transform: internals.transform });
     });
 
     lab.after(() => {
diff --git a/test/reporters.js b/test/reporters.js
index 8c1ada37..a98af60e 100755
--- a/test/reporters.js
+++ b/test/reporters.js
@@ -20,6 +20,7 @@ const internals = {};
 
 
 const lab = exports.lab = _Lab.script();
+const before = lab.before;
 const describe = lab.describe;
 const it = lab.it;
 const expect = Code.expect;
@@ -27,7 +28,10 @@ const expect = Code.expect;
 
 describe('Reporter', () => {
 
-    Lab.coverage.instrument({ coveragePath: Path.join(__dirname, './coverage/'), coverageExclude: 'exclude' });
+    before({}, async () => {
+
+        await Lab.coverage.instrument({ coveragePath: Path.join(__dirname, './coverage/'), coverageExclude: 'exclude' });
+    });
 
     it('outputs to a stream', async () => {
 
diff --git a/test/transform.js b/test/transform.js
index 16d7c75b..647cb679 100755
--- a/test/transform.js
+++ b/test/transform.js
@@ -38,13 +38,17 @@ const internals = {
 // Test shortcuts
 
 const lab = exports.lab = _Lab.script();
+const before = lab.before;
 const describe = lab.describe;
 const it = lab.it;
 const expect = Code.expect;
 
 describe('Transform', () => {
 
-    Lab.coverage.instrument({ coveragePath: Path.join(__dirname, './transform/'), coverageExclude: 'exclude', transform: internals.transform });
+    before({}, async () => {
+
+        await Lab.coverage.instrument({ coveragePath: Path.join(__dirname, './transform/'), coverageExclude: 'exclude', transform: internals.transform });
+    });
 
     it('instruments and measures coverage', async () => {
 
diff --git a/test/typescript.js b/test/typescript.js
index 40e702ea..bccfe736 100755
--- a/test/typescript.js
+++ b/test/typescript.js
@@ -6,6 +6,7 @@ const Path = require('path');
 const Code = require('@hapi/code');
 const _Lab = require('../test_runner');
 const RunCli = require('./run_cli');
+const Ts = require('typescript');
 const Typescript = require('../lib/modules/typescript');
 
 
@@ -53,6 +54,31 @@ describe('TypeScript', () => {
 
     describe('transform', () => {
 
+        it('errors when failing to find a tsconfig file', () => {
+
+            const path = Path.join(__dirname, 'cli', 'simple.js');
+
+            expect(
+                () => Typescript.extensions[0].transform(Fs.readFileSync(path, { encoding: 'utf8' }), path)
+            ).to.throw(/^Cannot find a tsconfig file for .+cli[\/\\]simple\.js/);
+        });
+
+        it('errors when unable to read a tsconfig file', (flags) => {
+
+            const path = Path.join(__dirname, 'cli_typescript', 'simple.ts');
+
+            const origReadFile = Ts.sys.readFile;
+            flags.onCleanup = () => Object.assign(Ts.sys, { readFile: origReadFile });
+            Ts.sys.readFile = () => {
+
+                throw new Error('Oops!');
+            };
+
+            expect(
+                () => Typescript.extensions[0].transform(Fs.readFileSync(path, { encoding: 'utf8' }), path)
+            ).to.throw(/^TypeScript config error in .+?cli_typescript\/tsconfig\.json: Cannot read file \'.+?\/cli_typescript\/tsconfig\.json\': Oops!/);
+        });
+
         it('generates embedded sourcemap with sourcesContent', () => {
 
             const smre = /\/\/\#\s*sourceMappingURL=data:application\/json[^,]+base64,(.*)\r?\n?$/;
@@ -65,5 +91,12 @@ describe('TypeScript', () => {
             expect(sourcemap.sourcesContent).to.exist();
             expect(sourcemap.sourcesContent).to.have.length(1);
         });
+
+        it('transforms identically when called multiple times', () => {
+            // This covers config file caching behavior, which is not directly observable by consumers.
+            const path = Path.join(__dirname, 'cli_typescript', 'simple.ts');
+            const transform = () => Typescript.extensions[0].transform(Fs.readFileSync(path, { encoding: 'utf8' }), path);
+            expect(transform()).to.equal(transform());
+        });
     });
 });