diff --git a/.eslintrc.js b/.eslintrc.js
new file mode 100644
index 0000000..c9098bc
--- /dev/null
+++ b/.eslintrc.js
@@ -0,0 +1,283 @@
+module.exports = {
+    "env": {
+        "es6": true,
+        "node": true
+    },
+    "globals": {
+      // react native
+      "window": true,
+      "__DEV__": true,
+      "localStorage": true
+    },
+    "extends": "eslint:recommended",
+    "parserOptions": {
+        "sourceType": "module"
+    },
+    "rules": {
+        "accessor-pairs": "error",
+        "array-bracket-spacing": "warn",
+        "array-callback-return": "warn",
+        "arrow-body-style": "warn",
+        "arrow-parens": [
+            "error",
+            "as-needed"
+        ],
+        "arrow-spacing": [
+            "error",
+            {
+                "after": true,
+                "before": true
+            }
+        ],
+        "block-scoped-var": "error",
+        "block-spacing": "error",
+        "brace-style": [
+            "error",
+            "1tbs"
+        ],
+        "callback-return": "error",
+        "camelcase": "warn",
+        "capitalized-comments": "off",
+        "class-methods-use-this": "error",
+        "comma-dangle": "off",
+        "comma-spacing": [
+            "error",
+            {
+                "after": true,
+                "before": false
+            }
+        ],
+        "comma-style": [
+            "error",
+            "last"
+        ],
+        "complexity": "error",
+        "computed-property-spacing": "error",
+        "consistent-return": "warn",
+        "consistent-this": "warn",
+        "curly": "off",
+        "default-case": "error",
+        "dot-location": "off",
+        "dot-notation": "warn",
+        "eol-last": "warn",
+        "eqeqeq": "warn",
+        "func-call-spacing": "error",
+        "func-name-matching": "error",
+        "func-names": "warn",
+        "func-style": "warn",
+        "generator-star-spacing": "off",
+        "global-require": "off",
+        "guard-for-in": "warn",
+        "handle-callback-err": "warn",
+        "id-blacklist": "error",
+        "id-length": "off",
+        "id-match": "error",
+        "indent": "off",
+        "init-declarations": "off",
+        "jsx-quotes": "error",
+        "key-spacing": "error",
+        "keyword-spacing": [
+            "error",
+            {
+                "after": true,
+                "before": true
+            }
+        ],
+        "line-comment-position": "warn",
+        "linebreak-style": [
+            "error",
+            "unix"
+        ],
+        "lines-around-comment": "warn",
+        "lines-around-directive": "error",
+        "max-depth": "error",
+        "max-len": "off",
+        "max-lines": "warn",
+        "max-nested-callbacks": "error",
+        "max-params": "warn",
+        "max-statements": "off",
+        "max-statements-per-line": "error",
+        "multiline-ternary": "warn",
+        "new-cap": "error",
+        "new-parens": "error",
+        "newline-after-var": "off",
+        "newline-before-return": "off",
+        "newline-per-chained-call": "warn",
+        "no-alert": "error",
+        "no-array-constructor": "error",
+        "no-await-in-loop": "error",
+        "no-bitwise": "error",
+        "no-caller": "error",
+        "no-case-declarations": "warn",
+        "no-catch-shadow": "warn",
+        "no-cond-assign": "warn",
+        "no-confusing-arrow": "error",
+        "no-console": "warn",
+        "no-constant-condition": "warn",
+        "no-continue": "warn",
+        "no-div-regex": "error",
+        "no-duplicate-imports": "error",
+        "no-else-return": "error",
+        "no-ex-assign": "off",
+        "no-empty": [
+            "error",
+            {
+                "allowEmptyCatch": true
+            }
+        ],
+        "no-empty-function": "off",
+        "no-eq-null": "warn",
+        "no-eval": "error",
+        "no-extend-native": "error",
+        "no-extra-bind": "error",
+        "no-extra-label": "error",
+        "no-extra-parens": "warn",
+        "no-extra-semi": "warn",
+        "no-floating-decimal": "error",
+        "no-implicit-coercion": "warn",
+        "no-implicit-globals": "error",
+        "no-implied-eval": "error",
+        "no-inline-comments": "off",
+        "no-inner-declarations": "warn",
+        "no-invalid-this": "warn",
+        "no-iterator": "error",
+        "no-label-var": "error",
+        "no-labels": "error",
+        "no-lone-blocks": "error",
+        "no-lonely-if": "warn",
+        "no-loop-func": "error",
+        "no-magic-numbers": "off",
+        "no-mixed-operators": "error",
+        "no-mixed-requires": "error",
+        "no-multi-assign": "warn",
+        "no-multi-spaces": "error",
+        "no-multi-str": "error",
+        "no-multiple-empty-lines": "error",
+        "no-native-reassign": "error",
+        "no-negated-condition": "warn",
+        "no-negated-in-lhs": "error",
+        "no-nested-ternary": "error",
+        "no-new": "error",
+        "no-new-func": "error",
+        "no-new-object": "error",
+        "no-new-require": "error",
+        "no-new-wrappers": "error",
+        "no-octal-escape": "error",
+        "no-param-reassign": "warn",
+        "no-path-concat": "error",
+        "no-process-env": "off",
+        "no-process-exit": "off",
+        "no-proto": "error",
+        "no-prototype-builtins": "error",
+        "no-restricted-globals": "error",
+        "no-restricted-imports": "error",
+        "no-restricted-modules": "error",
+        "no-restricted-properties": "error",
+        "no-restricted-syntax": "error",
+        "no-return-assign": "warn",
+        "no-return-await": "error",
+        "no-script-url": "error",
+        "no-self-compare": "error",
+        "no-sequences": "error",
+        "no-shadow": "warn",
+        "no-shadow-restricted-names": "error",
+        "no-spaced-func": "error",
+        "no-sync": "off",
+        "no-tabs": "error",
+        "no-template-curly-in-string": "error",
+        "no-ternary": "off",
+        "no-throw-literal": "error",
+        "no-trailing-spaces": "error",
+        "no-undef-init": "warn",
+        "no-undefined": "warn",
+        "no-underscore-dangle": "warn",
+        "no-unmodified-loop-condition": "error",
+        "no-unneeded-ternary": "error",
+        "no-unused-expressions": "error",
+        "no-unused-vars": "warn",
+        "no-use-before-define": "off",
+        "no-useless-call": "error",
+        "no-useless-computed-key": "error",
+        "no-useless-concat": "error",
+        "no-useless-constructor": "error",
+        "no-useless-escape": "warn",
+        "no-useless-rename": "error",
+        "no-useless-return": "error",
+        "no-var": "warn",
+        "no-void": "error",
+        "no-warning-comments": "warn",
+        "no-whitespace-before-property": "error",
+        "no-with": "error",
+        "object-curly-newline": "off",
+        "object-curly-spacing": [
+            "error",
+            "always"
+        ],
+        "object-property-newline": [
+            "error",
+            {
+                "allowMultiplePropertiesPerLine": true
+            }
+        ],
+        "object-shorthand": "warn",
+        "one-var": "off",
+        "one-var-declaration-per-line": "error",
+        "operator-assignment": "error",
+        "operator-linebreak": "error",
+        "padded-blocks": "off",
+        "prefer-const": "warn",
+        "prefer-destructuring": "warn",
+        "prefer-numeric-literals": "error",
+        "prefer-promise-reject-errors": "error",
+        "prefer-reflect": "warn",
+        "prefer-rest-params": "warn",
+        "prefer-spread": "warn",
+        "prefer-template": "off",
+        "quote-props": "off",
+        "quotes": "off",
+        "radix": "error",
+        "require-await": "error",
+        "require-jsdoc": "off",
+        "require-yield": "off",
+        "rest-spread-spacing": [
+            "error",
+            "never"
+        ],
+        "semi": "off",
+        "semi-spacing": "error",
+        "sort-imports": "error",
+        "sort-keys": "off",
+        "sort-vars": "error",
+        "space-before-blocks": "error",
+        "space-before-function-paren": "error",
+        "space-in-parens": [
+            "error",
+            "never"
+        ],
+        "space-infix-ops": "off",
+        "space-unary-ops": "error",
+        "spaced-comment": [
+            "error",
+            "always"
+        ],
+        "strict": "error",
+        "symbol-description": "error",
+        "template-curly-spacing": [
+            "error",
+            "never"
+        ],
+        "unicode-bom": [
+            "error",
+            "never"
+        ],
+        "valid-jsdoc": "warn",
+        "vars-on-top": "off",
+        "wrap-iife": "error",
+        "wrap-regex": "warn",
+        "yield-star-spacing": "error",
+        "yoda": [
+            "error",
+            "never"
+        ]
+    }
+};
diff --git a/browser.json b/browser.json
index 751b7ca..36cf75e 100644
--- a/browser.json
+++ b/browser.json
@@ -1,4 +1,5 @@
 {
+  "q": "bluebird-q",
   "zlib": "browserify-zlib",
   "console": "console-browserify",
   "constants": "constants-browserify",
@@ -21,5 +22,6 @@
   "stream": "stream-browserify",
   "timers": "timers-browserify",
   "tty": "tty-browserify",
-  "vm": "vm-browserify"
+  "vm": "vm-browserify",
+  "tls": false
 }
diff --git a/cmd.js b/cmd.js
index 3e98ed4..d3ccbc8 100755
--- a/cmd.js
+++ b/cmd.js
@@ -10,6 +10,7 @@ var deepEqual = require('deep-equal')
 var find = require('findit')
 var minimist = require('minimist')
 var parallel = require('run-parallel')
+var yarnlock = require('@yarnpkg/lockfile')
 var allShims = require('./shims')
 var coreList = require('./coreList')
 var browser = require('./browser')
@@ -18,12 +19,16 @@ var pkg = require(pkgPath)
 var hackFiles = require('./pkg-hacks')
 var argv = minimist(process.argv.slice(2), {
   alias: {
+    h: 'help',
     i: 'install',
     e: 'hack',
-    h: 'help'
+    o: 'overwrite',
+    y: 'yarn'
   }
 })
 
+var BASE_INSTALL_LINE = argv.yarn ? 'yarn add' : 'npm install --save'
+
 if (argv.help) {
   runHelp()
   process.exit(0)
@@ -62,7 +67,10 @@ function run () {
   }
 
   if (argv.install) {
-    installShims(toShim, function (err) {
+    installShims({
+      modules: toShim,
+      overwrite: argv.overwrite
+    }, function (err) {
       if (err) throw err
 
       runHacks()
@@ -83,36 +91,100 @@ function run () {
   }
 }
 
-function installShims (modulesToShim, done) {
-  var shimPkgNames = modulesToShim.map(function (m) {
+function installShims ({ modules, overwrite }, done) {
+  if (!overwrite) {
+    modules = modules.filter(name => {
+      const shimPackageName = browser[name] || name
+      if (pkg.dependencies[shimPackageName]) {
+        log(`not overwriting "${shimPackageName}"`)
+        return false
+      }
+
+      return true
+    })
+  }
+
+  var shimPkgNames = modules
+    .map(function (m) {
       return browser[m] || m
-    }).filter(function (shim) {
+    })
+    .filter(function (shim) {
       return !/^_/.test(shim) && shim.indexOf('/') === -1
     })
 
-  var existence = []
+  if (!shimPkgNames.length) {
+    return finish()
+  }
+
+  // Load the exact package versions from the lockfile
+  var lockfile
+  if (argv.yarn) {
+    if (fs.existsSync('yarn.lock')) {
+      let result = yarnlock.parse(fs.readFileSync('yarn.lock', 'utf8'))
+      if (result.type == 'success') {
+        lockfile = result.object
+      }
+    }
+  } else {
+    var lockpath = path.join(process.cwd(), 'package-lock.json')
+    if (fs.existsSync(lockpath)) {
+      let result = require(lockpath)
+      if (result && result.dependencies) {
+        lockfile = result.dependencies
+      }
+    }
+  }
+
   parallel(shimPkgNames.map(function (name) {
     var modPath = path.resolve('./node_modules/' + name)
-    return function (cb)  {
+    return function (cb) {
       fs.exists(modPath, function (exists) {
         if (!exists) return cb()
 
         var install = true
-        var pkgJson = require(modPath + '/package.json')
-        if (/^git\:\/\//.test(pkgJson._resolved)) {
-          var hash = allShims[name].split('#')[1]
-          if (hash && pkgJson.gitHead.indexOf(hash) === 0) {
-            install = false
+        if (lockfile) {
+          // Use the lockfile to resolve installed version of package
+          if (argv.yarn) {
+            if (`${name}@${allShims[name]}` in lockfile) {
+              install = false
+            }
+          } else {
+            var lockfileVer = (lockfile[name] || {}).version
+            var targetVer = allShims[name]
+            if (semver.valid(lockfileVer)) {
+              if (semver.satisfies(lockfileVer, targetVer)) {
+                install = false
+              }
+            } else if (lockfileVer) {
+              // To be considered up-to-date, we need an exact match,
+              // after doing some normalization of github url's
+              if (lockfileVer.startsWith('github:')) {
+                lockfileVer = lockfileVer.slice(7)
+              }
+              if (lockfileVer.indexOf(targetVer) == 0) {
+                install = false
+              }
+            }
           }
         } else {
-          var existingVer = pkgJson.version
-          if (semver.satisfies(existingVer, allShims[name])) {
-            install = false
+          // Fallback to using the version from the dependency's package.json
+          var pkgJson = require(modPath + '/package.json')
+          if (/^git\:\/\//.test(pkgJson._resolved)) {
+            var hash = allShims[name].split('#')[1]
+            if (hash && pkgJson.gitHead.indexOf(hash) === 0) {
+              install = false
+            }
+          } else {
+            var existingVerNpm5 = (/\-([^\-]+)\.tgz/.exec(pkgJson.version) || [null, null])[1]
+            var existingVer = existingVerNpm5 || pkgJson.version
+            if (semver.satisfies(existingVer, allShims[name])) {
+              install = false
+            }
           }
         }
 
         if (!install) {
-          console.log('not reinstalling ' + name)
+          log('not reinstalling ' + name)
           shimPkgNames.splice(shimPkgNames.indexOf(name), 1)
         }
 
@@ -126,24 +198,35 @@ function installShims (modulesToShim, done) {
       return finish()
     }
 
-    var installLine = 'npm install --save '
+    var installLine = BASE_INSTALL_LINE + ' '
     shimPkgNames.forEach(function (name) {
-      if (allShims[name].indexOf('/') === -1) {
-        console.log('installing from npm', name)
-        installLine += name + '@' + allShims[name]
+      let version = allShims[name]
+      if (!version) return
+      if (version.indexOf('/') === -1) {
+        if (argv.yarn) {
+          log('installing from yarn', name)
+        } else {
+          log('installing from npm', name)
+        }
+        installLine += name + '@' + version
       } else {
         // github url
-        console.log('installing from github', name)
-        installLine += allShims[name].match(/([^\/]+\/[^\/]+)$/)[1]
+        log('installing from github', name)
+        installLine += version.match(/([^\/]+\/[^\/]+)$/)[1]
       }
 
-      pkg.dependencies[name] = allShims[name]
+      pkg.dependencies[name] = version
       installLine += ' '
     })
 
     fs.writeFile(pkgPath, JSON.stringify(pkg, null, 2), function (err) {
       if (err) throw err
 
+      if (installLine.trim() === BASE_INSTALL_LINE) {
+        return finish()
+      }
+
+      log('installing:', installLine)
       proc.execSync(installLine, {
         cwd: process.cwd(),
         env: process.env,
@@ -152,17 +235,19 @@ function installShims (modulesToShim, done) {
 
       finish()
     })
-
-    console.log('installing:', installLine)
-    function finish () {
-      copyShim(done)
-    }
   })
+
+  function finish () {
+    copyShim(done)
+  }
 }
 
 function copyShim (cb) {
   fs.exists('./shim.js', function (exists) {
-    if (exists) return cb()
+    if (exists) {
+      log('not overwriting shim.js. For the latest version, see rn-nodeify/shim.js')
+      return cb()
+    }
 
     fs.readFile(path.join(__dirname, 'shim.js'), { encoding: 'utf8' }, function (err, contents) {
       if (err) return cb(err)
@@ -202,7 +287,7 @@ function fixPackageJSON (modules, file, overwrite) {
     }
 
     // if (shims[pkgJson.name]) {
-    //   console.log('skipping', pkgJson.name)
+    //   log('skipping', pkgJson.name)
     //   return
     // }
 
@@ -222,7 +307,7 @@ function fixPackageJSON (modules, file, overwrite) {
         depBrowser[p] = browser[p]
       } else {
         if (!overwrite && orgBrowser[p] !== browser[p]) {
-          console.log('not overwriting mapping', p, orgBrowser[p])
+          log('not overwriting mapping', p, orgBrowser[p])
         } else {
           depBrowser[p] = browser[p]
         }
@@ -230,12 +315,28 @@ function fixPackageJSON (modules, file, overwrite) {
     }
 
     modules.forEach(function (p) {
-      if (depBrowser[p] === false) {
-        console.log('removing browser exclude', file, p)
+      if (depBrowser[p] === false && browser[p] !== false) {
+        log('removing browser exclude', file, p)
         delete depBrowser[p]
       }
     })
 
+
+    const { main } = pkgJson
+    if (main) {
+      const alt = main.startsWith('./') ? main.slice(2) : './' + main
+      if (depBrowser[alt]) {
+        depBrowser[main] = depBrowser[alt]
+        log(`normalized "main" browser mapping in ${pkgJson.name}, fixed here: https://github.com/facebook/metro-bundler/pull/3`)
+        delete depBrowser[alt]
+      }
+    }
+
+    if (pkgJson.name === 'constants-browserify') {
+      // otherwise react-native packager chokes for some reason
+      delete depBrowser.constants
+    }
+
     if (!deepEqual(orgBrowser, depBrowser)) {
       pkgJson.browser = pkgJson['react-native'] = depBrowser
       delete pkgJson.browserify
@@ -249,7 +350,7 @@ function rethrow (err) {
 }
 
 function runHelp () {
-  console.log(function () {
+  log(function () {
     /*
     Usage:
         rn-nodeify --install dns,stream,http,https
@@ -260,9 +361,15 @@ function runHelp () {
         -h  --help                  show usage
         -e, --hack                  run package-specific hacks (list or leave blank to run all)
         -i, --install               install shims (list or leave blank to install all)
+        -o, --overwrite             updates installed packages if a newer version is available
+        -y, --yarn                  use yarn to install packages instead of npm (experimental)
 
     Please report bugs!  https://github.com/mvayngrib/rn-nodeify/issues
     */
   }.toString().split(/\n/).slice(2, -2).join('\n'))
   process.exit(0)
 }
+
+function log () {
+  console.log.apply(console, arguments)
+}
diff --git a/coreList.js b/coreList.js
index 71f2d1a..ebcf4c5 100644
--- a/coreList.js
+++ b/coreList.js
@@ -26,5 +26,7 @@ module.exports = [
   "url",
   "util",
   "net",
-  "vm"
+  "vm",
+  // note: tls doesn't have a shim
+  "tls"
 ]
diff --git a/package.json b/package.json
index 764bfca..b5d9f21 100644
--- a/package.json
+++ b/package.json
@@ -1,10 +1,15 @@
 {
   "name": "rn-nodeify",
-  "version": "7.0.1",
+  "repository": {
+    "type": "git",
+    "url": "https://github.com/mvayngrib/rn-nodeify.git"
+  },
+  "version": "8.2.0",
   "preferGlobal": true,
   "bin": "./cmd.js",
   "license": "MIT",
   "dependencies": {
+    "@yarnpkg/lockfile": "^1.0.0",
     "deep-equal": "^1.0.0",
     "findit": "^2.0.0",
     "fs-extra": "^0.22.1",
@@ -13,5 +18,12 @@
     "run-parallel": "^1.1.2",
     "semver": "^5.0.1",
     "xtend": "^4.0.0"
+  },
+  "scripts": {
+    "lint": "eslint --quiet --ignore-path .gitignore .",
+    "precommit": "npm run lint"
+  },
+  "devDependencies": {
+    "husky": "^0.14.3"
   }
 }
diff --git a/pkg-hacks.js b/pkg-hacks.js
index 2ddca82..f5d0991 100644
--- a/pkg-hacks.js
+++ b/pkg-hacks.js
@@ -5,6 +5,9 @@ var proc = require('child_process')
 var fs = require('fs-extra')
 var find = require('findit')
 var path = require('path')
+
+var localHackersFilename = '.rn-nodeify-hacks'
+var cwd = process.cwd()
 // var thisPkg = require('./package.json')
 
 // function loadDeps() {
@@ -26,14 +29,16 @@ var path = require('path')
 
 module.exports = function hackFiles (hacks) {
   var finder = find('./node_modules')
-  hacks = hacks || hackers.map(function (h) { return h.name })
+  hacks = hacks || getHackers(hackers).map(function (h) { return h.name })
 
   finder.on('file', function (file) {
-    if (!/\.(js|json)$/.test(file)
-      || /\/tests?\//.test(file)) {
+    if (!/\.(js|json)$/.test(file) ||
+      /\/tests?\//.test(file)) {
       return
     }
 
+    file = file.replace(/\\/g, path.posix.sep);
+
     var matchingHackers = hackers.filter(function (hacker) {
       return hacks.indexOf(hacker.name) !== -1 && hacker.regex.some(function (regex) {
         return regex.test(file)
@@ -60,7 +65,25 @@ module.exports = function hackFiles (hacks) {
   })
 }
 
+function getHackers(hackers) {
+  var allHacks = hackers
+  var localHacksFile = path.join(cwd, localHackersFilename)
+
+  try {
+    var localHacks = require(localHacksFile)
+
+    if (localHacks && localHacks.length) {
+      console.log('Loaded ' + localHacks.length + ' hacks from ' + localHacksFile)
+
+      allHacks = allHacks.concat(localHacks)
+    }
+  } catch (e) {
+    console.log('Not loading local hacks')
+  }
+
 
+  return allHacks
+}
 
 // loadDeps(hackFiles)
 
@@ -135,10 +158,18 @@ var hackers = [
   {
     name: 'rn-bundler',
     regex: [
-      /react\-packager\/src\/bundler\/bundle\.js/i
+      /react\-(?:native\/)?packager\/src\/bundler\/bundle\.js$/i,
+      /react\-(?:native\/)?packager\/src\/JSTransformer\/worker\/minify\.js$/i,
+      /metro\/src\/JSTransformer\/worker\/minify\.js$/i,
+      /metro-minify-uglify\/src\/minifier\.js$/i,
     ],
     hack: function (file, contents) {
-      var fixed = contents.replace(/(fromString: true,)(\s+)(outSourceMap)/, '$1$2mangle:false,$2$3')
+      if (contents.indexOf('mangle:false') !== -1) return
+
+      var fixed = contents
+        .replace('mangle: { toplevel: true }', 'mangle:false')
+        .replace(/(\s+)(fromString: true,)/, '$1$2$1mangle:false,')
+
       return contents === fixed ? null : fixed
     }
   },
@@ -160,7 +191,7 @@ var hackers = [
     regex: [
       /webtorrent\/lib\/fs-storage\.js/
     ],
-    hack: function(file, contents) {
+    hack: function (file, contents) {
       if (isInReactNative(file)) return
 
       var fixed = contents.replace(/fs\.existsSync\([^\)]*\)/g, 'false')
@@ -174,7 +205,7 @@ var hackers = [
     ],
     hack: function (file, contents) {
       var fixed = contents.replace(/typeof\ FileReaderSync \!\=\= \'undefined\'/, 'false')
-      return contents === fixed ? null  : fixed
+      return contents === fixed ? null : fixed
     }
   },
   {
@@ -221,12 +252,13 @@ var hackers = [
     regex: [
       /levelup\/lib\/util\.js$/
     ],
-    hack: function(file, contents) {
+    hack: function (file, contents) {
       if (isInReactNative(file)) return
 
       var fixed = contents
       fixed = fixed.replace("require('../package.json').devDependencies.leveldown", "'1.0.0'")
       fixed = fixed.replace("require('leveldown/package').version", "'1.0.0'")
+      fixed = fixed.replace("require('leveldown/package.json').version", "'1.0.0'")
       fixed = fixed.replace("require('leveldown')", "null")
 
       // var bad = '\'leveldown'
@@ -253,7 +285,7 @@ var hackers = [
     regex: [
       /level-jobs\/package\.json$/
     ],
-    hack: function(file, contents) {
+    hack: function (file, contents) {
       if (isInReactNative(file)) return
 
       var pkg
@@ -421,7 +453,7 @@ var hackers = [
     regex: [
       /bytewise\/bytewise\.js$/
     ],
-    hack: function(file, contents) {
+    hack: function (file, contents) {
       if (isInReactNative(file)) return
 
       var fixed = contents
@@ -509,7 +541,18 @@ var hackers = [
 
       return contents.replace(/_crypto\s+=\s+\(\s+g\.crypto\s+\|\|\s+g.msCrypto\s+\|\|\s+require\('crypto'\)\s+\)/, hack)
     }
-  }
+  },
+  {
+    name: 'version',
+    regex: [/pbkdf2/],
+    hack: function (file, contents) {
+      if (isInReactNative(file)) return
+
+      var fixed = contents.replace('process.version', '"' + process.version + '"')
+
+      return contents === fixed ? null : fixed
+    }
+  },
 ]
 
 function rewireMain (pkg) {
@@ -517,8 +560,7 @@ function rewireMain (pkg) {
     var main = pkg.browser || './index.js'
     pkg.browser = {}
     pkg.browser[pkg.main] = main
-  }
-  else if (typeof pkg.browser === 'undefined') {
+  } else if (typeof pkg.browser === 'undefined') {
     pkg.browser = {}
   }
 }
diff --git a/readme.md b/readme.md
index c0b105f..eb61253 100644
--- a/readme.md
+++ b/readme.md
@@ -2,6 +2,22 @@
 
 Run after npm install and you can use node core modules and npm modules that use them in your React Native app.
 
+## What is solves
+
+If your project has no non-React-Native dependencies, you don't need this module, and you should just check out ['./shims.js'](./shims.js) for the core node modules to use individually.
+
+However, with bigger projects that don't reimplement every wheel from scratch, somewhere in your dependency tree, something uses a core node module. I found myself building this because in my React Native app, I wanted to use [bitcoinjs-lib](https://github.com/bitcoinjs/bitcoinjs-lib), [levelup](https://github.com/Level/levelup), [bittorrent-dht](https://github.com/feross/bittorrent-dht), and lots of fun crypto. If that sounds like you, keep reading.
+
+## What it does
+
+`rn-nodeify --install`
+installs shims for core node modules, see ['./shims.js'](./shims.js) for the current mappings. It recurses down `node_modules` and modifies all the `package.json`'s in there to add/update the `browser` and `react-native` fields. It sounds scary because it is. However, it does work.
+
+`rn-nodeify --hack`
+Now that you're scared, I should also mention that there are some package-specific hacks (see ['./pkg-hacks.js'](./pkg-hacks.js)), for when the React Native packager choked on something that Webpack and Browserify swallowed.
+
+If you're looking for a saner approach, check out [ReactNativify](https://github.com/philikon/ReactNativify). I haven't tested it myself, but I think [philikon](https://github.com/philikon) will be happy to help.
+
 ## Usage
 
 ```bash
@@ -11,8 +27,8 @@ rn-nodeify <options>
 ## Options
 
 ```
---install     install node core shims (default: install all), fix the "browser" 
-              (later "react-native") fields in the package.json's of dependencies
+--install     install node core shims (default: install all), fix the "browser"
+              and "react-native" fields in the package.json's of dependencies
 --hack        hack individual packages that are known to make the React Native packager choke
 ```
 
@@ -48,6 +64,12 @@ rn-nodeify will create a `shim.js` file in your project root directory. The firs
 import './shim'
 ```
 
+Some shims may require linking libraries, be sure to run `react-native link` after installing new shims if you run into problems.
+
+### Local hacks
+
+You can create your own local hacks by adding a file named `.rn-nodeify-hacks` on your cwd path. This file should `export` a javascript array with the same syntax as the `hackers` variable in the `pkg-hacks.js` file. You can use this functionality to extend the the `--hack` capabilities of this package.
+
 ### Example Apps / Workflows
 
 * the [react-native-crypto](https://github.com/mvayngrib/react-native-crypto) package has an example workflow for using crypto in a React Native app
@@ -88,3 +110,8 @@ copied from [react-native-crypto](https://github.com/mvayngrib/react-native-cryp
 - when installing a package from git, the postinstall hook isn't triggered, run it manually instead (`npm run postinstall`)
 - restart the react-native packager after installing a module!
 - removing the packager cache helps as well sometimes (`rm -fr $TMPDIR/react-*`)
+- rn-nodeify currently uses `npm` to install shims. PRs are welcome to make it compatible with `yarn`
+- use `npm@3`. `npm@5` has some issues that cause `node_modules` to disappear. See:
+  - https://github.com/mvayngrib/rn-nodeify/issues/42
+  - https://github.com/infinitered/ignite/issues/1101
+  - https://github.com/npm/npm/issues/16839
diff --git a/shim.js b/shim.js
index ac5eb5a..65d986e 100644
--- a/shim.js
+++ b/shim.js
@@ -20,40 +20,3 @@ process.env['NODE_ENV'] = isDev ? 'development' : 'production'
 if (typeof localStorage !== 'undefined') {
   localStorage.debug = isDev ? '*' : ''
 }
-
-if (require('./package.json').dependencies['react-native-crypto']) {
-  const algos = require('browserify-sign/algos')
-  if (!algos.sha256) {
-    algos.sha256 = {
-      "sign": "ecdsa",
-      "hash": "sha256",
-      "id": new Buffer("")
-    }
-  }
-
-  if (typeof window === 'object') {
-    const wCrypto = window.crypto = window.crypto || {}
-    wCrypto.getRandomValues = wCrypto.getRandomValues || getRandomValues
-  }
-
-  const crypto = require('crypto')
-  const randomBytes = crypto.randomBytes
-  crypto.randomBytes = function (size, cb) {
-    if (cb) return randomBytes.apply(crypto, arguments)
-
-    const arr = new Buffer(size)
-    getRandomValues(arr)
-    return arr
-  }
-
-  crypto.getRandomValues = crypto.getRandomValues || getRandomValues
-
-  function getRandomValues (arr) {
-    // console.warn('WARNING: generating insecure psuedorandom number')
-    for (var i = 0; i < arr.length; i++) {
-      arr[i] = Math.random() * 256 | 0
-    }
-
-    return arr
-  }
-}
diff --git a/shims-browserify.js b/shims-browserify.js
index 7c201e0..5952ae2 100644
--- a/shims-browserify.js
+++ b/shims-browserify.js
@@ -4,7 +4,7 @@ module.exports = {
   "buffer": "^3.0.0",
   "inherits": "~2.0.1",
   "console-browserify": "^1.1.0",
-  "constants-browserify": "~0.0.1",
+  "constants-browserify": "^1.0.0",
   "crypto-browserify": "~3.2.6",
   "dns.js": "^1.0.1",
   "domain-browser": "~1.1.0",
@@ -27,6 +27,6 @@ module.exports = {
   "url": "~0.10.1",
   "util": "~0.10.1",
   "utp": "0.0.8",
-  "react-native-tcp": "^2.0.4",
+  "react-native-tcp": "^3.2.1",
   "vm-browserify": "~0.0.1"
 }
diff --git a/shims.js b/shims.js
index b295c4d..3c9c99b 100644
--- a/shims.js
+++ b/shims.js
@@ -1,12 +1,13 @@
 module.exports = {
+  "bluebird-q": "latest",
   "assert": "^1.1.1",
   "browserify-zlib": "~0.1.4",
   "buffer": "^4.9.1",
   "inherits": "^2.0.1",
   "console-browserify": "^1.1.0",
-  "constants-browserify": "~0.0.1",
-  "react-native-crypto": "^2.0.0",
-  "react-native-randombytes": "^2.1.0",
+  "constants-browserify": "^1.0.0",
+  "react-native-crypto": "^2.1.0",
+  "react-native-randombytes": "^3.0.0",
   "dns.js": "^1.0.1",
   "domain-browser": "^1.1.1",
   "events": "^1.0.0",
@@ -18,7 +19,7 @@ module.exports = {
   "punycode": "^1.2.4",
   "querystring-es3": "~0.2.0",
   "react-native-level-fs": "^3.0.0",
-  "react-native-udp": "^1.2.0",
+  "react-native-udp": "^2.1.0",
   "readable-stream": "1.0.33",
   // "stream-browserify": "substack/stream-browserify#fa56e68",
   "stream-browserify": "^1.0.0",
@@ -27,6 +28,6 @@ module.exports = {
   "tty-browserify": "0.0.0",
   "url": "~0.10.1",
   "util": "~0.10.3",
-  "react-native-tcp": "^2.0.4",
+  "react-native-tcp": "^3.2.1",
   "vm-browserify": "0.0.4"
 }