diff --git a/index.d.ts b/index.d.ts
new file mode 100644
index 0000000..41b2399
--- /dev/null
+++ b/index.d.ts
@@ -0,0 +1,73 @@
+// TypeScript Version: 2.4
+/// <reference types="node" />
+
+declare namespace requireDirectory {
+    /**
+     * @description function that checks path for whitelisting/blacklisting
+     * @param path path of required module
+     * @returns true if path have to be whitelisted/blacklisted, false otherwise
+     */
+    type CheckPathFn = (path: string) => boolean;
+
+    interface RequireDirectoryResult<T> {
+        /**
+         * @description module itself or hash of modules in subdirectory with name of this directory
+         */
+        [index: string]: RequireDirectoryResult<T> | T;
+    }
+    interface RequireDirectoryOptions<T, U = T> {
+        /**
+         * @description array of file extensions that will be included in resulting hash as modules
+         * @default "['js', 'json', 'coffee']"
+         */
+        extensions?: string[];
+        /**
+         * @description option to include subdirectories
+         * @default true
+         */
+        recurse?: boolean;
+        /**
+         * @description RegExp or function for whitelisting modules
+         * @default undefined
+         */
+        include?: RegExp | CheckPathFn;
+        /**
+         * @description RegExp or function for blacklisting modules
+         * @default undefined
+         */
+        exclude?: RegExp | CheckPathFn;
+        /**
+         * @description function for renaming modules in resulting hash
+         * @param name name of required module
+         * @returns transformed name of module
+         * @default "change nothing"
+         */
+        rename?(name: string): string;
+        /**
+         * @description function that will be called for each required module
+         * @param obj required module
+         * @returns transformed module OR nothing (in second case module itself will be added to hash)
+         * @default "change nothing"
+         */
+        visit?(obj: T): U | void;
+    }
+
+    /**
+     * @description default options that is used for "require-directory" module
+     */
+    const defaults: RequireDirectoryOptions<any>;
+}
+
+/**
+ * @description function for requiring directory content as hash of modules
+ * @param m module for which has will be created
+ * @param path path to directory, if you want to build hash for another one (default to __dirname)
+ * @param options object with options for require-directory call
+ * @returns hash of modules in specified directory
+ */
+declare function requireDirectory<T, U>(
+    m: NodeModule,
+    path?: string | requireDirectory.RequireDirectoryOptions<T, U>,
+    options?: requireDirectory.RequireDirectoryOptions<T, U>): requireDirectory.RequireDirectoryResult<U>;
+
+export = requireDirectory;
diff --git a/package-lock.json b/package-lock.json
new file mode 100644
index 0000000..fdb1a70
--- /dev/null
+++ b/package-lock.json
@@ -0,0 +1,407 @@
+{
+  "name": "require-directory",
+  "version": "2.1.1",
+  "lockfileVersion": 1,
+  "requires": true,
+  "dependencies": {
+    "@types/node": {
+      "version": "8.0.20",
+      "resolved": "https://registry.npmjs.org/@types/node/-/node-8.0.20.tgz",
+      "integrity": "sha512-MnB7YEpmLUyEWRVRhKpRs4swwqITnY8BcVFPoTuCl99SCplI/lLUiU5vcJ/OANDqwkpdIg0pDEM38K22KQT2RA==",
+      "dev": true
+    },
+    "balanced-match": {
+      "version": "1.0.0",
+      "resolved": "https://registry.npmjs.org/balanced-match/-/balanced-match-1.0.0.tgz",
+      "integrity": "sha1-ibTRmasr7kneFk6gK4nORi1xt2c=",
+      "dev": true
+    },
+    "brace-expansion": {
+      "version": "1.1.8",
+      "resolved": "https://registry.npmjs.org/brace-expansion/-/brace-expansion-1.1.8.tgz",
+      "integrity": "sha1-wHshHHyVLsH479Uad+8NHTmQopI=",
+      "dev": true,
+      "requires": {
+        "balanced-match": "1.0.0",
+        "concat-map": "0.0.1"
+      }
+    },
+    "cli": {
+      "version": "1.0.1",
+      "resolved": "https://registry.npmjs.org/cli/-/cli-1.0.1.tgz",
+      "integrity": "sha1-IoF1NPJL+klQw01TLUjsvGIbjBQ=",
+      "dev": true,
+      "requires": {
+        "exit": "0.1.2",
+        "glob": "7.1.2"
+      }
+    },
+    "commander": {
+      "version": "2.3.0",
+      "resolved": "https://registry.npmjs.org/commander/-/commander-2.3.0.tgz",
+      "integrity": "sha1-/UMOiJgy7DU7ms0d4hfBHLPu+HM=",
+      "dev": true
+    },
+    "concat-map": {
+      "version": "0.0.1",
+      "resolved": "https://registry.npmjs.org/concat-map/-/concat-map-0.0.1.tgz",
+      "integrity": "sha1-2Klr13/Wjfd5OnMDajug1UBdR3s=",
+      "dev": true
+    },
+    "console-browserify": {
+      "version": "1.1.0",
+      "resolved": "https://registry.npmjs.org/console-browserify/-/console-browserify-1.1.0.tgz",
+      "integrity": "sha1-8CQcRXMKn8YyOyBtvzjtx0HQuxA=",
+      "dev": true,
+      "requires": {
+        "date-now": "0.1.4"
+      }
+    },
+    "core-util-is": {
+      "version": "1.0.2",
+      "resolved": "https://registry.npmjs.org/core-util-is/-/core-util-is-1.0.2.tgz",
+      "integrity": "sha1-tf1UIgqivFq1eqtxQMlAdUUDwac=",
+      "dev": true
+    },
+    "date-now": {
+      "version": "0.1.4",
+      "resolved": "https://registry.npmjs.org/date-now/-/date-now-0.1.4.tgz",
+      "integrity": "sha1-6vQ5/U1ISK105cx9vvIAZyueNFs=",
+      "dev": true
+    },
+    "debug": {
+      "version": "2.2.0",
+      "resolved": "https://registry.npmjs.org/debug/-/debug-2.2.0.tgz",
+      "integrity": "sha1-+HBX6ZWxofauaklgZkE3vFbwOdo=",
+      "dev": true,
+      "requires": {
+        "ms": "0.7.1"
+      }
+    },
+    "diff": {
+      "version": "1.4.0",
+      "resolved": "https://registry.npmjs.org/diff/-/diff-1.4.0.tgz",
+      "integrity": "sha1-fyjS657nsVqX79ic5j3P2qPMur8=",
+      "dev": true
+    },
+    "dom-serializer": {
+      "version": "0.1.0",
+      "resolved": "https://registry.npmjs.org/dom-serializer/-/dom-serializer-0.1.0.tgz",
+      "integrity": "sha1-BzxpdUbOB4DOI75KKOKT5AvDDII=",
+      "dev": true,
+      "requires": {
+        "domelementtype": "1.1.3",
+        "entities": "1.1.1"
+      },
+      "dependencies": {
+        "domelementtype": {
+          "version": "1.1.3",
+          "resolved": "https://registry.npmjs.org/domelementtype/-/domelementtype-1.1.3.tgz",
+          "integrity": "sha1-vSh3PiZCiBrsUVRJJCmcXNgiGFs=",
+          "dev": true
+        },
+        "entities": {
+          "version": "1.1.1",
+          "resolved": "https://registry.npmjs.org/entities/-/entities-1.1.1.tgz",
+          "integrity": "sha1-blwtClYhtdra7O+AuQ7ftc13cvA=",
+          "dev": true
+        }
+      }
+    },
+    "domelementtype": {
+      "version": "1.3.0",
+      "resolved": "https://registry.npmjs.org/domelementtype/-/domelementtype-1.3.0.tgz",
+      "integrity": "sha1-sXrtguirWeUt2cGbF1bg/BhyBMI=",
+      "dev": true
+    },
+    "domhandler": {
+      "version": "2.3.0",
+      "resolved": "https://registry.npmjs.org/domhandler/-/domhandler-2.3.0.tgz",
+      "integrity": "sha1-LeWaCCLVAn+r/28DLCsloqir5zg=",
+      "dev": true,
+      "requires": {
+        "domelementtype": "1.3.0"
+      }
+    },
+    "domutils": {
+      "version": "1.5.1",
+      "resolved": "https://registry.npmjs.org/domutils/-/domutils-1.5.1.tgz",
+      "integrity": "sha1-3NhIiib1Y9YQeeSMn3t+Mjc2gs8=",
+      "dev": true,
+      "requires": {
+        "dom-serializer": "0.1.0",
+        "domelementtype": "1.3.0"
+      }
+    },
+    "entities": {
+      "version": "1.0.0",
+      "resolved": "https://registry.npmjs.org/entities/-/entities-1.0.0.tgz",
+      "integrity": "sha1-sph6o4ITR/zeZCsk/fyeT7cSvyY=",
+      "dev": true
+    },
+    "escape-string-regexp": {
+      "version": "1.0.2",
+      "resolved": "https://registry.npmjs.org/escape-string-regexp/-/escape-string-regexp-1.0.2.tgz",
+      "integrity": "sha1-Tbwv5nTnGUnK8/smlc5/LcHZqNE=",
+      "dev": true
+    },
+    "exit": {
+      "version": "0.1.2",
+      "resolved": "https://registry.npmjs.org/exit/-/exit-0.1.2.tgz",
+      "integrity": "sha1-BjJjj42HfMghB9MKD/8aF8uhzQw=",
+      "dev": true
+    },
+    "fs.realpath": {
+      "version": "1.0.0",
+      "resolved": "https://registry.npmjs.org/fs.realpath/-/fs.realpath-1.0.0.tgz",
+      "integrity": "sha1-FQStJSMVjKpA20onh8sBQRmU6k8=",
+      "dev": true
+    },
+    "glob": {
+      "version": "7.1.2",
+      "resolved": "https://registry.npmjs.org/glob/-/glob-7.1.2.tgz",
+      "integrity": "sha512-MJTUg1kjuLeQCJ+ccE4Vpa6kKVXkPYJ2mOCQyUuKLcLQsdrMCpBPUi8qVE6+YuaJkozeA9NusTAw3hLr8Xe5EQ==",
+      "dev": true,
+      "requires": {
+        "fs.realpath": "1.0.0",
+        "inflight": "1.0.6",
+        "inherits": "2.0.3",
+        "minimatch": "3.0.4",
+        "once": "1.4.0",
+        "path-is-absolute": "1.0.1"
+      }
+    },
+    "growl": {
+      "version": "1.9.2",
+      "resolved": "https://registry.npmjs.org/growl/-/growl-1.9.2.tgz",
+      "integrity": "sha1-Dqd0NxXbjY3ixe3hd14bRayFwC8=",
+      "dev": true
+    },
+    "htmlparser2": {
+      "version": "3.8.3",
+      "resolved": "https://registry.npmjs.org/htmlparser2/-/htmlparser2-3.8.3.tgz",
+      "integrity": "sha1-mWwosZFRaovoZQGn15dX5ccMEGg=",
+      "dev": true,
+      "requires": {
+        "domelementtype": "1.3.0",
+        "domhandler": "2.3.0",
+        "domutils": "1.5.1",
+        "entities": "1.0.0",
+        "readable-stream": "1.1.14"
+      }
+    },
+    "inflight": {
+      "version": "1.0.6",
+      "resolved": "https://registry.npmjs.org/inflight/-/inflight-1.0.6.tgz",
+      "integrity": "sha1-Sb1jMdfQLQwJvJEKEHW6gWW1bfk=",
+      "dev": true,
+      "requires": {
+        "once": "1.4.0",
+        "wrappy": "1.0.2"
+      }
+    },
+    "inherits": {
+      "version": "2.0.3",
+      "resolved": "https://registry.npmjs.org/inherits/-/inherits-2.0.3.tgz",
+      "integrity": "sha1-Yzwsg+PaQqUC9SRmAiSA9CCCYd4=",
+      "dev": true
+    },
+    "isarray": {
+      "version": "0.0.1",
+      "resolved": "https://registry.npmjs.org/isarray/-/isarray-0.0.1.tgz",
+      "integrity": "sha1-ihis/Kmo9Bd+Cav8YDiTmwXR7t8=",
+      "dev": true
+    },
+    "jade": {
+      "version": "0.26.3",
+      "resolved": "https://registry.npmjs.org/jade/-/jade-0.26.3.tgz",
+      "integrity": "sha1-jxDXl32NefL2/4YqgbBRPMslaGw=",
+      "dev": true,
+      "requires": {
+        "commander": "0.6.1",
+        "mkdirp": "0.3.0"
+      },
+      "dependencies": {
+        "commander": {
+          "version": "0.6.1",
+          "resolved": "https://registry.npmjs.org/commander/-/commander-0.6.1.tgz",
+          "integrity": "sha1-+mihT2qUXVTbvlDYzbMyDp47GgY=",
+          "dev": true
+        },
+        "mkdirp": {
+          "version": "0.3.0",
+          "resolved": "https://registry.npmjs.org/mkdirp/-/mkdirp-0.3.0.tgz",
+          "integrity": "sha1-G79asbqCevI1dRQ0kEJkVfSB/h4=",
+          "dev": true
+        }
+      }
+    },
+    "jshint": {
+      "version": "2.9.5",
+      "resolved": "https://registry.npmjs.org/jshint/-/jshint-2.9.5.tgz",
+      "integrity": "sha1-HnJSkVzmgbQIJ+4UJIxG006apiw=",
+      "dev": true,
+      "requires": {
+        "cli": "1.0.1",
+        "console-browserify": "1.1.0",
+        "exit": "0.1.2",
+        "htmlparser2": "3.8.3",
+        "lodash": "3.7.0",
+        "minimatch": "3.0.4",
+        "shelljs": "0.3.0",
+        "strip-json-comments": "1.0.4"
+      }
+    },
+    "lodash": {
+      "version": "3.7.0",
+      "resolved": "https://registry.npmjs.org/lodash/-/lodash-3.7.0.tgz",
+      "integrity": "sha1-Nni9irmVBXwHreg27S7wh9qBHUU=",
+      "dev": true
+    },
+    "lru-cache": {
+      "version": "2.7.3",
+      "resolved": "https://registry.npmjs.org/lru-cache/-/lru-cache-2.7.3.tgz",
+      "integrity": "sha1-bUUk6LlV+V1PW1iFHOId1y+06VI=",
+      "dev": true
+    },
+    "minimatch": {
+      "version": "3.0.4",
+      "resolved": "https://registry.npmjs.org/minimatch/-/minimatch-3.0.4.tgz",
+      "integrity": "sha512-yJHVQEhyqPLUTgt9B83PXu6W3rx4MvvHvSUvToogpwoGDOUQ+yDrR0HRot+yOCdCO7u4hX3pWft6kWBBcqh0UA==",
+      "dev": true,
+      "requires": {
+        "brace-expansion": "1.1.8"
+      }
+    },
+    "minimist": {
+      "version": "0.0.8",
+      "resolved": "https://registry.npmjs.org/minimist/-/minimist-0.0.8.tgz",
+      "integrity": "sha1-hX/Kv8M5fSYluCKCYuhqp6ARsF0=",
+      "dev": true
+    },
+    "mkdirp": {
+      "version": "0.5.1",
+      "resolved": "https://registry.npmjs.org/mkdirp/-/mkdirp-0.5.1.tgz",
+      "integrity": "sha1-MAV0OOrGz3+MR2fzhkjWaX11yQM=",
+      "dev": true,
+      "requires": {
+        "minimist": "0.0.8"
+      }
+    },
+    "mocha": {
+      "version": "2.5.3",
+      "resolved": "https://registry.npmjs.org/mocha/-/mocha-2.5.3.tgz",
+      "integrity": "sha1-FhvlvetJZ3HrmzV0UFC2IrWu/Fg=",
+      "dev": true,
+      "requires": {
+        "commander": "2.3.0",
+        "debug": "2.2.0",
+        "diff": "1.4.0",
+        "escape-string-regexp": "1.0.2",
+        "glob": "3.2.11",
+        "growl": "1.9.2",
+        "jade": "0.26.3",
+        "mkdirp": "0.5.1",
+        "supports-color": "1.2.0",
+        "to-iso-string": "0.0.2"
+      },
+      "dependencies": {
+        "glob": {
+          "version": "3.2.11",
+          "resolved": "https://registry.npmjs.org/glob/-/glob-3.2.11.tgz",
+          "integrity": "sha1-Spc/Y1uRkPcV0QmH1cAP0oFevj0=",
+          "dev": true,
+          "requires": {
+            "inherits": "2.0.3",
+            "minimatch": "0.3.0"
+          }
+        },
+        "minimatch": {
+          "version": "0.3.0",
+          "resolved": "https://registry.npmjs.org/minimatch/-/minimatch-0.3.0.tgz",
+          "integrity": "sha1-J12O2qxPG7MyZHIInnlJyDlGmd0=",
+          "dev": true,
+          "requires": {
+            "lru-cache": "2.7.3",
+            "sigmund": "1.0.1"
+          }
+        }
+      }
+    },
+    "ms": {
+      "version": "0.7.1",
+      "resolved": "https://registry.npmjs.org/ms/-/ms-0.7.1.tgz",
+      "integrity": "sha1-nNE8A62/8ltl7/3nzoZO6VIBcJg=",
+      "dev": true
+    },
+    "once": {
+      "version": "1.4.0",
+      "resolved": "https://registry.npmjs.org/once/-/once-1.4.0.tgz",
+      "integrity": "sha1-WDsap3WWHUsROsF9nFC6753Xa9E=",
+      "dev": true,
+      "requires": {
+        "wrappy": "1.0.2"
+      }
+    },
+    "path-is-absolute": {
+      "version": "1.0.1",
+      "resolved": "https://registry.npmjs.org/path-is-absolute/-/path-is-absolute-1.0.1.tgz",
+      "integrity": "sha1-F0uSaHNVNP+8es5r9TpanhtcX18=",
+      "dev": true
+    },
+    "readable-stream": {
+      "version": "1.1.14",
+      "resolved": "https://registry.npmjs.org/readable-stream/-/readable-stream-1.1.14.tgz",
+      "integrity": "sha1-fPTFTvZI44EwhMY23SB54WbAgdk=",
+      "dev": true,
+      "requires": {
+        "core-util-is": "1.0.2",
+        "inherits": "2.0.3",
+        "isarray": "0.0.1",
+        "string_decoder": "0.10.31"
+      }
+    },
+    "shelljs": {
+      "version": "0.3.0",
+      "resolved": "https://registry.npmjs.org/shelljs/-/shelljs-0.3.0.tgz",
+      "integrity": "sha1-NZbmMHp4FUT1kfN9phg2DzHbV7E=",
+      "dev": true
+    },
+    "sigmund": {
+      "version": "1.0.1",
+      "resolved": "https://registry.npmjs.org/sigmund/-/sigmund-1.0.1.tgz",
+      "integrity": "sha1-P/IfGYytIXX587eBhT/ZTQ0ZtZA=",
+      "dev": true
+    },
+    "string_decoder": {
+      "version": "0.10.31",
+      "resolved": "https://registry.npmjs.org/string_decoder/-/string_decoder-0.10.31.tgz",
+      "integrity": "sha1-YuIDvEF2bGwoyfyEMB2rHFMQ+pQ=",
+      "dev": true
+    },
+    "strip-json-comments": {
+      "version": "1.0.4",
+      "resolved": "https://registry.npmjs.org/strip-json-comments/-/strip-json-comments-1.0.4.tgz",
+      "integrity": "sha1-HhX7ysl9Pumb8tc7TGVrCCu6+5E=",
+      "dev": true
+    },
+    "supports-color": {
+      "version": "1.2.0",
+      "resolved": "https://registry.npmjs.org/supports-color/-/supports-color-1.2.0.tgz",
+      "integrity": "sha1-/x7R5hFp0Gs88tWI4YixjYhH4X4=",
+      "dev": true
+    },
+    "to-iso-string": {
+      "version": "0.0.2",
+      "resolved": "https://registry.npmjs.org/to-iso-string/-/to-iso-string-0.0.2.tgz",
+      "integrity": "sha1-TcGeZk38y+Jb2NtQiwDG2hWCVdE=",
+      "dev": true
+    },
+    "wrappy": {
+      "version": "1.0.2",
+      "resolved": "https://registry.npmjs.org/wrappy/-/wrappy-1.0.2.tgz",
+      "integrity": "sha1-tSQ9jz7BqjXxNkYFvA0QNuMKtp8=",
+      "dev": true
+    }
+  }
+}
diff --git a/package.json b/package.json
index 25ece4b..0d45fc1 100644
--- a/package.json
+++ b/package.json
@@ -11,6 +11,7 @@
   ],
   "homepage": "https://github.com/troygoode/node-require-directory/",
   "main": "index.js",
+  "types": "index.d.ts",
   "repository": {
     "type": "git",
     "url": "git://github.com/troygoode/node-require-directory.git"
@@ -30,6 +31,7 @@
     "node": ">=0.10.0"
   },
   "devDependencies": {
+    "@types/node": "^8.0.20",
     "jshint": "^2.6.0",
     "mocha": "^2.1.0"
   },