diff --git a/bin/nyc.js b/bin/nyc.js
index 841205a21..6dd78bf46 100755
--- a/bin/nyc.js
+++ b/bin/nyc.js
@@ -4,7 +4,6 @@
 const configUtil = require('../lib/config-util')
 const foreground = require('foreground-child')
 const NYC = require('../index.js')
-const processArgs = require('../lib/process-args')
 
 const sw = require('spawn-wrap')
 const wrapper = require.resolve('./wrap.js')
@@ -13,13 +12,10 @@ const wrapper = require.resolve('./wrap.js')
 // we keep these values in a few different forms,
 // used in the various execution contexts of nyc:
 // reporting, instrumenting subprocesses, etc.
-const yargs = configUtil.buildYargs()
-const instrumenterArgs = processArgs.hideInstrumenteeArgs()
-const config = configUtil.loadConfig(yargs.parse(instrumenterArgs))
-configUtil.addCommandsAndHelp(yargs)
-const argv = yargs.config(config).parse(instrumenterArgs)
 
 async function main () {
+  const { argv, childArgs, yargs } = await configUtil()
+
   if (['check-coverage', 'report', 'instrument', 'merge'].includes(argv._[0])) {
     // look in lib/commands for logic.
     return
@@ -68,11 +64,7 @@ async function main () {
   // set process.exitCode. Keep track so that both children are run, but
   // a non-zero exit codes in either one leads to an overall non-zero exit code.
   process.exitCode = 0
-  foreground(processArgs.hideInstrumenterArgs(
-    // use the same argv description, but don't exit
-    // for flags like --help.
-    configUtil.buildYargs().parse(process.argv.slice(2))
-  ), async () => {
+  foreground(childArgs, async () => {
     var mainChildExitCode = process.exitCode
 
     await nyc.writeProcessIndex()
diff --git a/index.js b/index.js
index 6df5dd03c..8b45915b1 100755
--- a/index.js
+++ b/index.js
@@ -492,15 +492,8 @@ class NYC {
   eachReport (filenames, iterator, baseDirectory) {
     baseDirectory = baseDirectory || this.tempDirectory()
 
-    if (typeof filenames === 'function') {
-      iterator = filenames
-      filenames = undefined
-    }
-
-    var _this = this
-    var files = filenames || fs.readdirSync(baseDirectory)
-
-    files.forEach(function (f) {
+    const files = filenames || fs.readdirSync(baseDirectory)
+    files.forEach(f => {
       var report
       try {
         report = JSON.parse(fs.readFileSync(
@@ -508,7 +501,7 @@ class NYC {
           'utf-8'
         ))
 
-        _this.sourceMaps.reloadCachedSourceMapsSync(report)
+        this.sourceMaps.reloadCachedSourceMapsSync(report)
       } catch (e) { // handle corrupt JSON output.
         report = {}
       }
diff --git a/lib/config-util.js b/lib/config-util.js
index 177469b60..3acf94a6d 100644
--- a/lib/config-util.js
+++ b/lib/config-util.js
@@ -1,61 +1,26 @@
 'use strict'
 
-const fs = require('fs')
 const path = require('path')
 const findUp = require('find-up')
 const testExclude = require('test-exclude')
 const Yargs = require('yargs/yargs')
 
-var Config = {}
+const processArgs = require('./process-args')
+const { loadNycConfig } = require('@istanbuljs/load-nyc-config')
 
-function guessCWD (cwd) {
+async function guessCWD (cwd) {
   cwd = cwd || process.env.NYC_CWD || process.cwd()
-  const pkgPath = findUp.sync('package.json', { cwd: cwd })
+  const pkgPath = await findUp('package.json', { cwd })
   if (pkgPath) {
     cwd = path.dirname(pkgPath)
   }
-  return cwd
-}
-
-Config.loadConfig = function (argv, cwd) {
-  const rcOptions = [
-    argv.nycrcPath || '.nycrc',
-    '.nycrc.json',
-    '.nycrc.yml',
-    '.nycrc.yaml',
-    'nyc.config.js'
-  ]
-  const rcPath = findUp.sync(rcOptions, { cwd: guessCWD(cwd) })
-  let config = {}
-
-  if (rcPath) {
-    const rcExt = path.extname(rcPath.toLowerCase())
-    if (rcExt === '.js') {
-      config = require(rcPath)
-    } else if (rcExt === '.yml' || rcExt === '.yaml') {
-      config = require('js-yaml').load(
-        fs.readFileSync(rcPath, 'utf8')
-      )
-    } else {
-      config = JSON.parse(
-        fs.readFileSync(rcPath, 'utf-8')
-      )
-    }
-  }
-
-  if (config.require) config.require = [].concat(config.require)
-  if (config.extension) config.extension = [].concat(config.extension)
-  if (config.exclude) config.exclude = [].concat(config.exclude)
-  if (config.include) config.include = [].concat(config.include)
 
-  return config
+  return cwd
 }
 
-// build a yargs object, omitting any settings
-// that would cause the application to exit early.
-Config.buildYargs = function (cwd) {
-  cwd = guessCWD(cwd)
-  return Yargs([])
+async function processConfig (cwd) {
+  cwd = await guessCWD(cwd)
+  const yargs = Yargs([])
     .usage('$0 [command] [options]')
     .usage('$0 [options] [bin-to-instrument]')
     .option('reporter', {
@@ -243,7 +208,6 @@ Config.buildYargs = function (cwd) {
       global: false
     })
     .option('nycrc-path', {
-      default: '.nycrc',
       description: 'specify a different .nycrc path',
       global: false
     })
@@ -269,7 +233,6 @@ Config.buildYargs = function (cwd) {
       type: 'boolean',
       global: false
     })
-    .pkgConf('nyc', cwd)
     .example('$0 npm test', 'instrument your tests with coverage')
     .example('$0 --require @babel/register npm test', 'instrument your tests with coverage and transpile with Babel')
     .example('$0 report --reporter=text-lcov', 'output lcov report after running your tests')
@@ -278,20 +241,30 @@ Config.buildYargs = function (cwd) {
     .boolean('version')
     .help(false)
     .version(false)
-}
 
-// we add operations that would make yargs
-// exit post-hoc, allowing for a multi-pass
-// parsing step.
-Config.addCommandsAndHelp = function (yargs) {
-  return yargs
+  const instrumenterArgs = processArgs.hideInstrumenteeArgs()
+
+  // This yargs.parse must come before any options that exit post-hoc
+  const childArgs = processArgs.hideInstrumenterArgs(yargs.parse(process.argv.slice(2)))
+  const config = await loadNycConfig(yargs.parse(instrumenterArgs))
+
+  yargs
+    .config(config)
     .help('h')
     .alias('h', 'help')
     .version()
-    .command(require('../lib/commands/check-coverage'))
-    .command(require('../lib/commands/instrument'))
-    .command(require('../lib/commands/report'))
-    .command(require('../lib/commands/merge'))
+    .command(require('./commands/check-coverage'))
+    .command(require('./commands/instrument'))
+    .command(require('./commands/report'))
+    .command(require('./commands/merge'))
+
+  return {
+    get argv () {
+      return yargs.parse(instrumenterArgs)
+    },
+    childArgs,
+    yargs
+  }
 }
 
-module.exports = Config
+module.exports = processConfig
diff --git a/package-lock.json b/package-lock.json
index 9b6b38de9..df614afa4 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -109,6 +109,17 @@
         "to-fast-properties": "^2.0.0"
       }
     },
+    "@istanbuljs/load-nyc-config": {
+      "version": "1.0.0-alpha.0",
+      "resolved": "https://registry.npmjs.org/@istanbuljs/load-nyc-config/-/load-nyc-config-1.0.0-alpha.0.tgz",
+      "integrity": "sha512-tDRosscSl5tXCN2rYsfRddj/sl8ApLm30ByOhGFpMtCzjVbunPTwwexHFjxcPycSN6pUunUhOW+AcTfb9MB+gA==",
+      "requires": {
+        "camelcase": "^5.3.1",
+        "find-up": "^4.1.0",
+        "js-yaml": "^3.13.1",
+        "resolve-from": "^5.0.0"
+      }
+    },
     "@istanbuljs/schema": {
       "version": "0.1.0",
       "resolved": "https://registry.npmjs.org/@istanbuljs/schema/-/schema-0.1.0.tgz",
diff --git a/package.json b/package.json
index 44eb7a48a..7e5de9d8e 100644
--- a/package.json
+++ b/package.json
@@ -68,6 +68,7 @@
   "author": "Ben Coe <ben@npmjs.com>",
   "license": "ISC",
   "dependencies": {
+    "@istanbuljs/load-nyc-config": "^1.0.0-alpha.0",
     "caching-transform": "^4.0.0",
     "convert-source-map": "^1.6.0",
     "cp-file": "^7.0.0",
diff --git a/tap-snapshots/test-nyc-integration.js-TAP.test.js b/tap-snapshots/test-nyc-integration.js-TAP.test.js
index 41f257465..83d458618 100644
--- a/tap-snapshots/test-nyc-integration.js-TAP.test.js
+++ b/tap-snapshots/test-nyc-integration.js-TAP.test.js
@@ -16,6 +16,21 @@ All files |   44.44 |      100 |   33.33 |   44.44 |
 
 `
 
+exports[`test/nyc-integration.js TAP --all instruments unknown extensions as js > stdout 1`] = `
+run
+------------------------|---------|----------|---------|---------|-------------------
+File                    | % Stmts | % Branch | % Funcs | % Lines | Uncovered Line #s 
+------------------------|---------|----------|---------|---------|-------------------
+All files               |   11.11 |      100 |       0 |   11.11 |                   
+ check-instrumented.es6 |       0 |      100 |       0 |       0 | 5,6               
+ check-instrumented.js  |       0 |      100 |       0 |       0 | 5,6               
+ not-loaded.es6         |       0 |      100 |     100 |       0 | 1,2               
+ not-loaded.js          |       0 |      100 |     100 |       0 | 1,2               
+ run.js                 |     100 |      100 |     100 |     100 |                   
+------------------------|---------|----------|---------|---------|-------------------
+
+`
+
 exports[`test/nyc-integration.js TAP --all uses source-maps to exclude original sources from reports > stdout 1`] = `
 ----------|---------|----------|---------|---------|-------------------
 File      | % Stmts | % Branch | % Funcs | % Lines | Uncovered Line #s 
@@ -838,6 +853,30 @@ exports[`test/nyc-integration.js TAP passes configuration via environment variab
 ]
 `
 
+exports[`test/nyc-integration.js TAP produce-source-map enabled > stdout 1`] = `
+Error: Blarrh
+    at blah (./stack-trace.js:3:1)
+----------------|---------|----------|---------|---------|-------------------
+File            | % Stmts | % Branch | % Funcs | % Lines | Uncovered Line #s 
+----------------|---------|----------|---------|---------|-------------------
+All files       |     100 |      100 |     100 |     100 |                   
+ stack-trace.js |     100 |      100 |     100 |     100 |                   
+----------------|---------|----------|---------|---------|-------------------
+
+`
+
+exports[`test/nyc-integration.js TAP produce-source-map not enabled > stdout 1`] = `
+Error: Blarrh
+    at blah (./stack-trace.js:1:1037)
+----------------|---------|----------|---------|---------|-------------------
+File            | % Stmts | % Branch | % Funcs | % Lines | Uncovered Line #s 
+----------------|---------|----------|---------|---------|-------------------
+All files       |     100 |      100 |     100 |     100 |                   
+ stack-trace.js |     100 |      100 |     100 |     100 |                   
+----------------|---------|----------|---------|---------|-------------------
+
+`
+
 exports[`test/nyc-integration.js TAP recursive run does not throw > stdout 1`] = `
 
 `
diff --git a/test/add-all-files.js b/test/add-all-files.js
index eab3e58a2..38750dc7f 100644
--- a/test/add-all-files.js
+++ b/test/add-all-files.js
@@ -7,9 +7,8 @@ const t = require('tap')
 const ap = require('any-path')
 
 const NYC = require('../self-coverage')
-const configUtil = require('../self-coverage/lib/config-util')
 
-const resetState = require('./helpers/reset-state')
+const { parseArgv, resetState } = require('./helpers')
 
 const fixtures = path.resolve(__dirname, 'fixtures')
 const transpileHook = path.resolve(__dirname, 'fixtures/transpile-hook')
@@ -17,7 +16,7 @@ const transpileHook = path.resolve(__dirname, 'fixtures/transpile-hook')
 t.beforeEach(resetState)
 
 t.test('outputs an empty coverage report for all files that are not excluded', async t => {
-  const nyc = new NYC(configUtil.buildYargs(fixtures).parse())
+  const nyc = new NYC(await parseArgv(fixtures))
   await nyc.reset()
   await nyc.addAllFiles()
 
@@ -32,7 +31,7 @@ t.test('outputs an empty coverage report for all files that are not excluded', a
 
 t.test('outputs an empty coverage report for multiple configured extensions', async t => {
   const cwd = path.resolve(fixtures, './conf-multiple-extensions')
-  const nyc = new NYC(configUtil.buildYargs(cwd).parse())
+  const nyc = new NYC(await parseArgv(cwd))
   await nyc.reset()
   await nyc.addAllFiles()
 
@@ -61,7 +60,7 @@ t.test('transpiles .js files added via addAllFiles', async t => {
     'utf-8'
   )
 
-  const nyc = new NYC(configUtil.buildYargs(fixtures).parse(['--require', transpileHook]))
+  const nyc = new NYC(await parseArgv(fixtures, ['--require', transpileHook]))
   await nyc.reset()
   await nyc.addAllFiles()
 
@@ -83,7 +82,7 @@ t.test('does not attempt to transpile files when they are excluded', async t =>
     'utf-8'
   )
 
-  const nyc = new NYC(configUtil.buildYargs(fixtures).parse([
+  const nyc = new NYC(await parseArgv(fixtures, [
     `--require=${transpileHook}`,
     '--extension=.do-not-transpile',
     '--include=needs-transpile.do-not-transpile'
@@ -103,10 +102,10 @@ t.test('transpiles non-.js files added via addAllFiles', async t => {
     'utf-8'
   )
 
-  const nyc = (new NYC(configUtil.buildYargs(fixtures).parse([
+  const nyc = new NYC(await parseArgv(fixtures, [
     `--require=${transpileHook}`,
     '--extension=.whatever'
-  ])))
+  ]))
 
   await nyc.reset()
   await nyc.addAllFiles()
diff --git a/test/cache.js b/test/cache.js
index b2d7c982c..f8176fa87 100644
--- a/test/cache.js
+++ b/test/cache.js
@@ -7,16 +7,15 @@ const t = require('tap')
 const rimraf = promisify(require('rimraf'))
 
 const NYC = require('../self-coverage')
-const configUtil = require('../self-coverage/lib/config-util')
 
-const { resetState, runNYC } = require('./helpers')
+const { parseArgv, resetState, runNYC } = require('./helpers')
 
 const fixtures = path.resolve(__dirname, './fixtures')
 
 t.beforeEach(resetState)
 
 async function cacheTest (t, script) {
-  const nyc = new NYC(configUtil.buildYargs(fixtures).parse())
+  const nyc = new NYC(await parseArgv(fixtures))
   await rimraf(nyc.cacheDirectory)
 
   const { status } = await runNYC({
diff --git a/test/config.js b/test/config.js
index 9163d8cc3..62b440c87 100644
--- a/test/config.js
+++ b/test/config.js
@@ -5,22 +5,23 @@ const path = require('path')
 const { test } = require('tap')
 
 const NYC = require('../self-coverage')
-const configUtil = require('../self-coverage/lib/config-util')
+
+const { parseArgv } = require('./helpers')
 
 test("loads 'exclude' patterns from package.json#nyc", async t => {
-  const nyc = new NYC(configUtil.buildYargs(path.resolve(__dirname, './fixtures')).parse())
+  const nyc = new NYC(await parseArgv(path.resolve(__dirname, './fixtures')))
 
   t.strictEqual(nyc.exclude.exclude.length, 8)
 })
 
 test("loads 'extension' patterns from package.json#nyc", async t => {
-  const nyc = new NYC(configUtil.buildYargs(path.resolve(__dirname, './fixtures/conf-multiple-extensions')).parse())
+  const nyc = new NYC(await parseArgv(path.resolve(__dirname, './fixtures/conf-multiple-extensions')))
 
   t.strictEqual(nyc.extensions.length, 3)
 })
 
 test("ignores 'include' option if it's falsy or []", async t => {
-  const nyc1 = new NYC(configUtil.buildYargs(path.resolve(__dirname, './fixtures/conf-empty')).parse())
+  const nyc1 = new NYC(await parseArgv(path.resolve(__dirname, './fixtures/conf-empty')))
 
   t.strictEqual(nyc1.exclude.include, false)
 
@@ -32,7 +33,7 @@ test("ignores 'include' option if it's falsy or []", async t => {
 })
 
 test("ignores 'exclude' option if it's falsy", async t => {
-  const nyc = new NYC(configUtil.buildYargs(path.resolve(__dirname, './fixtures/conf-empty')).parse())
+  const nyc = new NYC(await parseArgv(path.resolve(__dirname, './fixtures/conf-empty')))
 
   t.strictEqual(nyc.exclude.exclude.length, 15)
 })
diff --git a/test/cwd.js b/test/cwd.js
index b62681cc1..b079bf034 100644
--- a/test/cwd.js
+++ b/test/cwd.js
@@ -5,14 +5,15 @@ const path = require('path')
 const t = require('tap')
 
 const NYC = require('../self-coverage')
-const configUtil = require('../self-coverage/lib/config-util')
+
+const { parseArgv } = require('./helpers')
 
 t.beforeEach(async () => {
   delete process.env.NYC_CWD
 })
 
 t.test('sets cwd to process.cwd() if no environment variable is set', async t => {
-  const nyc = new NYC(configUtil.buildYargs().parse())
+  const nyc = new NYC(await parseArgv())
 
   t.strictEqual(nyc.cwd, process.cwd())
 })
@@ -20,19 +21,19 @@ t.test('sets cwd to process.cwd() if no environment variable is set', async t =>
 t.test('uses NYC_CWD environment variable for cwd if it is set', async t => {
   const fixtures = path.resolve(__dirname, './fixtures')
   process.env.NYC_CWD = fixtures
-  const nyc = new NYC(configUtil.buildYargs().parse())
+  const nyc = new NYC(await parseArgv())
 
   t.strictEqual(nyc.cwd, fixtures)
 })
 
 t.test('will look upwards for package.json from cwd', async t => {
-  const nyc = new NYC(configUtil.buildYargs(__dirname).parse())
+  const nyc = new NYC(await parseArgv(__dirname))
 
   t.strictEqual(nyc.cwd, path.join(__dirname, '..'))
 })
 
 t.test('uses --cwd for cwd if it is set (highest priority and does not look upwards for package.json) ', async t => {
-  const nyc = new NYC(configUtil.buildYargs(__dirname).parse(['--cwd', __dirname]))
+  const nyc = new NYC(await parseArgv(__dirname, ['--cwd', __dirname]))
 
   t.strictEqual(nyc.cwd, __dirname)
 })
diff --git a/test/fixtures/conf-multiple-extensions/run.js b/test/fixtures/conf-multiple-extensions/run.js
new file mode 100644
index 000000000..b63af05a6
--- /dev/null
+++ b/test/fixtures/conf-multiple-extensions/run.js
@@ -0,0 +1,4 @@
+#!/usr/bin/env node
+'use strict';
+
+console.log('run');
diff --git a/test/helpers/index.js b/test/helpers/index.js
index b5c3001a6..4041a0fe5 100644
--- a/test/helpers/index.js
+++ b/test/helpers/index.js
@@ -11,5 +11,6 @@ module.exports = {
   testFailure: require('./test-failure'),
   runNYC: require('./run-nyc'),
   tempDirSetup: require('./temp-dir-setup'),
-  envCheckConfig: require('./env-check-config')
+  envCheckConfig: require('./env-check-config'),
+  parseArgv: require('./parse-argv')
 }
diff --git a/test/helpers/parse-argv.js b/test/helpers/parse-argv.js
new file mode 100644
index 000000000..2e3c12de5
--- /dev/null
+++ b/test/helpers/parse-argv.js
@@ -0,0 +1,9 @@
+const configUtil = require('../../self-coverage/lib/config-util')
+
+async function parseArgv (cwd, argv) {
+  const { yargs } = await configUtil(cwd)
+
+  return yargs.parse(argv)
+}
+
+module.exports = parseArgv
diff --git a/test/helpers/source-map-support.js b/test/helpers/source-map-support.js
new file mode 100644
index 000000000..43ad83aeb
--- /dev/null
+++ b/test/helpers/source-map-support.js
@@ -0,0 +1,3 @@
+'use strict'
+
+require('source-map-support').install({ hookRequire: true })
diff --git a/test/nyc-integration.js b/test/nyc-integration.js
index 9e4a6daa7..ba68d2280 100644
--- a/test/nyc-integration.js
+++ b/test/nyc-integration.js
@@ -586,3 +586,8 @@ t.test('reports error if input directory is missing', t => testFailure(t, {
 t.test('reports error if input is not a directory', t => testFailure(t, {
   args: ['merge', './package.json']
 }))
+
+t.test('--all instruments unknown extensions as js', t => testSuccess(t, {
+  cwd: path.resolve(fixturesCLI, '../conf-multiple-extensions'),
+  args: ['--all', process.execPath, './run.js']
+}))
diff --git a/test/report.js b/test/report.js
index 5668cbb12..645cbb14b 100644
--- a/test/report.js
+++ b/test/report.js
@@ -9,9 +9,8 @@ const isWindows = require('is-windows')()
 const rimraf = promisify(require('rimraf'))
 
 const NYC = require('../self-coverage')
-const configUtil = require('../self-coverage/lib/config-util')
 
-const { runNYC, resetState } = require('./helpers')
+const { parseArgv, runNYC, resetState } = require('./helpers')
 
 const fixtures = path.resolve(__dirname, 'fixtures')
 
@@ -24,7 +23,7 @@ async function testSignal (t, signal) {
     return
   }
 
-  const nyc = new NYC(configUtil.buildYargs(fixtures).parse())
+  const nyc = new NYC(await parseArgv(fixtures))
   await runNYC({
     args: [`./${signal}.js`],
     cwd: fixtures
@@ -41,9 +40,10 @@ t.test('writes coverage report when process is killed with SIGTERM', t => testSi
 t.test('writes coverage report when process is killed with SIGINT', t => testSignal(t, 'sigint'))
 
 t.test('allows coverage report to be output in an alternative directory', async t => {
-  const nyc = new NYC(configUtil.buildYargs().parse(
-    ['--report-dir=./alternative-report', '--reporter=lcov']
-  ))
+  const nyc = new NYC(await parseArgv(undefined, [
+    '--report-dir=./alternative-report',
+    '--reporter=lcov'
+  ]))
   await nyc.reset()
 
   await nyc.report()
diff --git a/test/should-instrument.js b/test/should-instrument.js
index 81b612914..8afc3d858 100644
--- a/test/should-instrument.js
+++ b/test/should-instrument.js
@@ -1,13 +1,15 @@
 const path = require('path')
 const NYC = require('../self-coverage')
-const configUtil = require('../self-coverage/lib/config-util')
+
+const { parseArgv } = require('./helpers')
+
 const fixtures = path.resolve(__dirname, './fixtures')
 
 const t = require('tap')
 
 const rootDir = path.resolve('/')
-t.test('should exclude appropriately with defaults', t => {
-  const nyc = new NYC(configUtil.buildYargs(rootDir).parse([
+t.test('should exclude appropriately with defaults', async t => {
+  const nyc = new NYC(await parseArgv(rootDir, [
     '--exclude=test/**',
     '--exclude=test{,-*}.js',
     '--exclude=**/*.test.js',
@@ -26,11 +28,10 @@ t.test('should exclude appropriately with defaults', t => {
   t.false(nyc.exclude.shouldInstrument(path.join(rootDir, 'foo/bar/test.js'), '.\\test.js'))
   t.false(nyc.exclude.shouldInstrument(path.join(rootDir, 'foo/bar/foo.test.js'), './foo.test.js'))
   t.false(nyc.exclude.shouldInstrument(path.join(rootDir, 'foo/bar/__tests__/foo.js'), './__tests__/foo.js'))
-  t.done()
 })
 
-t.test('should exclude appropriately with config.exclude', t => {
-  const nyc = new NYC(configUtil.buildYargs(fixtures).parse())
+t.test('should exclude appropriately with config.exclude', async t => {
+  const nyc = new NYC(await parseArgv(fixtures))
 
   // fixtures/package.json configures excludes: "blarg", "blerg"
   t.false(nyc.exclude.shouldInstrument(path.join(rootDir, 'blarg.js'), 'blarg.js'))
@@ -38,33 +39,29 @@ t.test('should exclude appropriately with config.exclude', t => {
   t.false(nyc.exclude.shouldInstrument(path.join(rootDir, 'blerg.js'), 'blerg.js'))
   t.false(nyc.exclude.shouldInstrument(path.join(rootDir, 'blerg.js'), './blerg.js'))
   t.false(nyc.exclude.shouldInstrument(path.join(rootDir, 'blerg.js'), '.\\blerg.js'))
-  t.done()
 })
 
-t.test('should exclude outside of the current working directory', t => {
-  const nyc = new NYC(configUtil.buildYargs(path.join(rootDir, 'foo')).parse())
+t.test('should exclude outside of the current working directory', async t => {
+  const nyc = new NYC(await parseArgv(path.join(rootDir, 'foo')))
   t.false(nyc.exclude.shouldInstrument(path.join(rootDir, 'bar.js'), '../bar.js'))
-  t.done()
 })
 
-t.test('should not exclude if the current working directory is inside node_modules', t => {
+t.test('should not exclude if the current working directory is inside node_modules', async t => {
   const cwd = path.join(rootDir, 'node_modules', 'foo')
-  const nyc = new NYC(configUtil.buildYargs(cwd).parse())
+  const nyc = new NYC(await parseArgv(cwd))
   t.true(nyc.exclude.shouldInstrument(path.join(cwd, 'bar.js'), './bar.js'))
   t.true(nyc.exclude.shouldInstrument(path.join(cwd, 'bar.js'), '.\\bar.js'))
-  t.done()
 })
 
-t.test('allows files to be explicitly included, rather than excluded', t => {
-  const nyc = new NYC(configUtil.buildYargs(rootDir).parse(['--include=foo.js']))
+t.test('allows files to be explicitly included, rather than excluded', async t => {
+  const nyc = new NYC(await parseArgv(rootDir, ['--include=foo.js']))
 
   t.true(nyc.exclude.shouldInstrument(path.join(rootDir, 'foo.js'), 'foo.js'))
   t.false(nyc.exclude.shouldInstrument(path.join(rootDir, 'index.js'), 'index.js'))
-  t.done()
 })
 
-t.test('exclude overrides include', t => {
-  const nyc = new NYC(configUtil.buildYargs(rootDir).parse([
+t.test('exclude overrides include', async t => {
+  const nyc = new NYC(await parseArgv(rootDir, [
     '--include=foo.js',
     '--include=test.js',
     '--exclude=**/node_modules/**',
@@ -74,5 +71,4 @@ t.test('exclude overrides include', t => {
 
   t.true(nyc.exclude.shouldInstrument(path.join(rootDir, 'foo.js'), 'foo.js'))
   t.false(nyc.exclude.shouldInstrument(path.join(rootDir, 'test.js'), 'test.js'))
-  t.done()
 })
diff --git a/test/source-map-support.js b/test/source-map-support.js
index a68f95cd1..3f2ac11b5 100644
--- a/test/source-map-support.js
+++ b/test/source-map-support.js
@@ -3,9 +3,8 @@
 const t = require('tap')
 
 const NYC = require('../self-coverage')
-const configUtil = require('../self-coverage/lib/config-util')
 
-const resetState = require('./helpers/reset-state')
+const { parseArgv, resetState } = require('./helpers')
 
 // we test exit handlers in nyc-integration.js.
 NYC.prototype._wrapExit = () => {}
@@ -15,7 +14,7 @@ require('source-map-support').install({ hookRequire: true })
 t.beforeEach(resetState)
 
 t.test('handles stack traces', async t => {
-  const nyc = new NYC(configUtil.buildYargs().parse('--produce-source-map'))
+  const nyc = new NYC(await parseArgv(undefined, ['--produce-source-map']))
   await nyc.reset()
   nyc.wrap()
 
@@ -25,7 +24,7 @@ t.test('handles stack traces', async t => {
 })
 
 t.test('does not handle stack traces when disabled', async t => {
-  const nyc = new NYC(configUtil.buildYargs().parse())
+  const nyc = new NYC(await parseArgv())
   await nyc.reset()
   nyc.wrap()
 
diff --git a/test/wrap.js b/test/wrap.js
index c78ea4fcb..2d28c2a2b 100644
--- a/test/wrap.js
+++ b/test/wrap.js
@@ -6,9 +6,8 @@ const path = require('path')
 const t = require('tap')
 
 const NYC = require('../self-coverage')
-const configUtil = require('../self-coverage/lib/config-util')
 
-const resetState = require('./helpers/reset-state')
+const { parseArgv, resetState } = require('./helpers')
 
 // we test exit handlers in nyc-integration.js.
 NYC.prototype._wrapExit = () => {}
@@ -19,7 +18,7 @@ const configMultExt = path.resolve(fixtures, 'conf-multiple-extensions')
 t.beforeEach(resetState)
 
 t.test('wraps modules with coverage counters when they are required', async t => {
-  const nyc = new NYC(configUtil.buildYargs().parse())
+  const nyc = new NYC(await parseArgv())
   await nyc.reset()
   nyc.wrap()
 
@@ -36,7 +35,7 @@ t.test('wraps modules with coverage counters when the custom require hook compil
     module._compile(fs.readFileSync(filename, 'utf8'), filename)
   }
 
-  const nyc = new NYC(configUtil.buildYargs().parse())
+  const nyc = new NYC(await parseArgv())
   await nyc.reset()
   nyc.wrap()
 
@@ -49,7 +48,7 @@ t.test('wraps modules with coverage counters when the custom require hook compil
 })
 
 t.test('assigns a function to custom extensions', async t => {
-  const nyc = new NYC(configUtil.buildYargs(configMultExt).parse())
+  const nyc = new NYC(await parseArgv(configMultExt))
   await nyc.reset()
   nyc.wrap()
 
@@ -62,7 +61,7 @@ t.test('assigns a function to custom extensions', async t => {
 
 t.test('calls the `_handleJs` function for custom file extensions', async t => {
   const required = {}
-  const nyc = new NYC(configUtil.buildYargs(configMultExt).parse())
+  const nyc = new NYC(await parseArgv(configMultExt))
 
   nyc._handleJs = (code, options) => {
     if (options.filename.includes('check-instrumented.es6')) {
@@ -86,7 +85,7 @@ t.test('calls the `_handleJs` function for custom file extensions', async t => {
 })
 
 t.test('does not output coverage for files that have not been included, by default', async t => {
-  const nyc = new NYC(configUtil.buildYargs(process.cwd()).parse())
+  const nyc = new NYC(await parseArgv(process.cwd()))
   nyc.wrap()
   await nyc.reset()
 
@@ -95,7 +94,7 @@ t.test('does not output coverage for files that have not been included, by defau
 })
 
 t.test('tracks coverage appropriately once the file is required', async t => {
-  const nyc = new NYC(configUtil.buildYargs(fixtures).parse())
+  const nyc = new NYC(await parseArgv(fixtures))
   await nyc.reset()
   nyc.wrap()