diff --git a/.npmignore b/.npmignore
new file mode 100644
index 0000000..f0a5ec8
--- /dev/null
+++ b/.npmignore
@@ -0,0 +1,5 @@
+/tests/
+/examples/
+/run-tests.js
+/.travis.yml
+/.npmignore
diff --git a/.travis.yml b/.travis.yml
index c1b06ae..bfd88d9 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -7,5 +7,3 @@ node_js:
   - "4.2"
   - "4.1"
   - "4.0"
-  - "0.10"
-  - "iojs"
diff --git a/BUILD.md b/BUILD.md
deleted file mode 100644
index 54cc874..0000000
--- a/BUILD.md
+++ /dev/null
@@ -1,36 +0,0 @@
-# Build instructions
-ng-annotate is written in ES6 constlet style and uses defs.js to transpile
-to ES5, via an optional build step, so that it can execute without the
-`--harmony` flag passed to node.
-
-The git repository contains the original constlet style source code as well
-as the build scripts. It does not contain build artefacts (transpiled or
-bundled source).
-
-The build scripts populates the `build/es5` directory.
-The NPM package contains a snapshot of the git repository at the time as
-well as `build/es5`. `package.json` refers to the transpiled version in
-`build/es5`, so there's no need to execute node with `--harmony` when
-running a `npm -g` installed `ng-annotate` from the command line or when
-doing a `require("ng-annotate")` of the same.
-
-If you clone the git repository then don't forget to also `npm install` the
-dependencies (see `package.json`).
-
-If you want to run ng-annotate in its original form (rather than
-transpiled), for instance if you're hacking on it, then just run the tool
-via `ng-annotate-harmony` (not a NPM exported binary but check the package
-root) or include it as a library via
-`require("ng-annotate/ng-annotate-main")`. This applies to a git clone just
-as well as the NPM package.
-
-`run-tests.js` is the test runner. Run it on the original source via
-`node --harmony run-tests.js` or `npm test`. The tests are run automatically
-in the build scripts.
-
-To build, `cd build` then run `./build.sh` for defs transpilation.
-`./clean.sh` removes the build artefacts.
-
-I use `prepare.sh` to prepare a release tarball for NPM publishing.
-
-Happy hacking!
diff --git a/CHANGES.md b/CHANGES.md
index 871d1f7..0610d64 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -1,3 +1,6 @@
+## UNRELEASED
+ * Require node>=4.0.0.
+
 ## v1.6.0 2017-05-28
  * Switch from tilde ~ dependencies to ^ caret dependencies.
 
diff --git a/build/build.sh b/build/build.sh
deleted file mode 100755
index a6874f5..0000000
--- a/build/build.sh
+++ /dev/null
@@ -1,28 +0,0 @@
-#!/bin/bash
-echo "beginning ng-annotate defs-build"
-rm -rf es5
-mkdir es5
-
-declare -a files=(generate-sourcemap.js lut.js ng-annotate.js ng-annotate-main.js nginject.js run-tests.js scope.js scopetools.js traverse.js optionals/angular-dashboard-framework.js)
-DEFS="../node_modules/.bin/defs"
-if [[ ! -f "$DEFS" ]]; then DEFS="../../../../node_modules/.bin/defs" ; fi
-if [[ ! -f "$DEFS" ]]; then DEFS="defs" ; fi
-
-for i in ${files[@]}
-do
-  echo "building $i with defs"
-  mkdir -p es5/$(dirname $i)
-  $DEFS ../$i > es5/$i
-done
-
-cp ng-annotate es5/
-
-echo "hard-coding version"
-node --harmony inline-version.js
-
-cd es5
-
-echo "running tests (in es5 mode i.e. without --harmony)"
-cp -r ../../tests .
-/usr/bin/env node run-tests.js
-echo "done self-build"
diff --git a/build/clean.sh b/build/clean.sh
deleted file mode 100755
index f922ec7..0000000
--- a/build/clean.sh
+++ /dev/null
@@ -1,4 +0,0 @@
-#!/bin/sh
-echo "cleaning build files"
-rm -rf es5 browser npm
-echo "done cleaning"
diff --git a/build/defs-config.json b/build/defs-config.json
deleted file mode 120000
index 9e007f5..0000000
--- a/build/defs-config.json
+++ /dev/null
@@ -1 +0,0 @@
-../defs-config.json
\ No newline at end of file
diff --git a/build/es5/ng-annotate b/build/es5/ng-annotate
deleted file mode 100755
index 22e0e09..0000000
--- a/build/es5/ng-annotate
+++ /dev/null
@@ -1,3 +0,0 @@
-#!/bin/sh
-echo "Error: ng-annotate has not been built.\nRetry after doing this: cd <ng-annotate-path>; npm install; cd build; ./build.sh"
-exit 1
diff --git a/build/es5/ng-annotate-main.js b/build/es5/ng-annotate-main.js
deleted file mode 100644
index db6a432..0000000
--- a/build/es5/ng-annotate-main.js
+++ /dev/null
@@ -1,2 +0,0 @@
-console.error("Error: ng-annotate has not been built.\nRetry after doing this: cd <ng-annotate-path>; npm install; cd build; ./build.sh");
-process.exit(1)
diff --git a/build/inline-version.js b/build/inline-version.js
deleted file mode 100644
index 8249e56..0000000
--- a/build/inline-version.js
+++ /dev/null
@@ -1,6 +0,0 @@
-const version = require("../package.json").version
-const fs = require("fs");
-
-const src = String(fs.readFileSync("es5/ng-annotate.js"));
-const dst = src.replace('require("./package.json").version', JSON.stringify(version));
-fs.writeFileSync("es5/ng-annotate.js", dst);
diff --git a/build/prepare.sh b/build/prepare.sh
deleted file mode 100755
index b223696..0000000
--- a/build/prepare.sh
+++ /dev/null
@@ -1,17 +0,0 @@
-#!/bin/sh
-cd ..
-rm -rf build/npm
-mkdir build/npm
-git archive fork -o build/npm/ng-annotate-patched.tar --prefix=ng-annotate-patched/
-cd build/npm
-tar xf ng-annotate-patched.tar && rm ng-annotate-patched.tar
-cd ng-annotate-patched/build
-./build.sh
-# delete build scripts
-rm *.sh *.js defs-config.json ng-annotate
-# delete .gitignore
-rm ../.gitignore
-# delete large test artifacts
-rm ../tests/angular.js ../build/es5/tests/angular.js
-cd ../..
-tar czf ng-annotate-patched.tgz ng-annotate-patched && rm -rf ng-annotate-patched
diff --git a/defs-config.json b/defs-config.json
deleted file mode 100644
index c6abf36..0000000
--- a/defs-config.json
+++ /dev/null
@@ -1,6 +0,0 @@
-{
-    "environments": ["node"],
-    "disallowVars": true,
-    "disallowDuplicated": true,
-    "disallowUnknownReferences": true
-}
diff --git a/build/ng-annotate b/ng-annotate
similarity index 100%
rename from build/ng-annotate
rename to ng-annotate
diff --git a/ng-annotate-harmony b/ng-annotate-harmony
deleted file mode 100755
index ed6c9ae..0000000
--- a/ng-annotate-harmony
+++ /dev/null
@@ -1,4 +0,0 @@
-#!/bin/sh
-rdlkf() { [ -L "$1" ] && (local lk="$(readlink "$1")"; local d="$(dirname "$1")"; cd "$d"; local l="$(rdlkf "$lk")"; ([[ "$l" = /* ]] && echo "$l" || echo "$d/$l")) || echo "$1"; }
-DIR="$(dirname "$(rdlkf "$0")")"
-/usr/bin/env node --harmony "$DIR/ng-annotate.js" "$@"
diff --git a/package-lock.json b/package-lock.json
index 174d0f4..9c16a45 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -9,17 +9,6 @@
       "resolved": "https://registry.npmjs.org/acorn/-/acorn-5.1.2.tgz",
       "integrity": "sha512-o96FZLJBPY1lvTuJylGA9Bk3t/GKPPJG8H0ydQQl01crzwJgspa4AEIq/pVTXigmK0PHVQhiAtn8WMBLL9D2WA=="
     },
-    "align-text": {
-      "version": "0.1.4",
-      "resolved": "https://registry.npmjs.org/align-text/-/align-text-0.1.4.tgz",
-      "integrity": "sha1-DNkKVhCT810KmSVsIrcGlDP60Rc=",
-      "dev": true,
-      "requires": {
-        "kind-of": "3.2.2",
-        "longest": "1.0.1",
-        "repeat-string": "1.6.1"
-      }
-    },
     "alter": {
       "version": "0.2.0",
       "resolved": "https://registry.npmjs.org/alter/-/alter-0.2.0.tgz",
@@ -28,53 +17,6 @@
         "stable": "0.1.6"
       }
     },
-    "ast-traverse": {
-      "version": "0.1.1",
-      "resolved": "https://registry.npmjs.org/ast-traverse/-/ast-traverse-0.1.1.tgz",
-      "integrity": "sha1-ac8rg4bxnc2hux4F1o/jWdiJfeY=",
-      "dev": true
-    },
-    "breakable": {
-      "version": "1.0.0",
-      "resolved": "https://registry.npmjs.org/breakable/-/breakable-1.0.0.tgz",
-      "integrity": "sha1-eEp5eRWjjq0nutRWtVcstLuqeME=",
-      "dev": true
-    },
-    "camelcase": {
-      "version": "1.2.1",
-      "resolved": "https://registry.npmjs.org/camelcase/-/camelcase-1.2.1.tgz",
-      "integrity": "sha1-m7UwTS4LVmmLLHWLCKPqqdqlijk=",
-      "dev": true
-    },
-    "center-align": {
-      "version": "0.1.3",
-      "resolved": "https://registry.npmjs.org/center-align/-/center-align-0.1.3.tgz",
-      "integrity": "sha1-qg0yYptu6XIgBBHL1EYckHvCt60=",
-      "dev": true,
-      "requires": {
-        "align-text": "0.1.4",
-        "lazy-cache": "1.0.4"
-      }
-    },
-    "cliui": {
-      "version": "2.1.0",
-      "resolved": "https://registry.npmjs.org/cliui/-/cliui-2.1.0.tgz",
-      "integrity": "sha1-S0dXYP+AJkx2LDoXGQMukcf+oNE=",
-      "dev": true,
-      "requires": {
-        "center-align": "0.1.3",
-        "right-align": "0.1.3",
-        "wordwrap": "0.0.2"
-      },
-      "dependencies": {
-        "wordwrap": {
-          "version": "0.0.2",
-          "resolved": "https://registry.npmjs.org/wordwrap/-/wordwrap-0.0.2.tgz",
-          "integrity": "sha1-t5Zpu0LstAn4PVg8rVLKF+qhZD8=",
-          "dev": true
-        }
-      }
-    },
     "coffee-script": {
       "version": "1.12.7",
       "resolved": "https://registry.npmjs.org/coffee-script/-/coffee-script-1.12.7.tgz",
@@ -86,90 +28,18 @@
       "resolved": "https://registry.npmjs.org/convert-source-map/-/convert-source-map-1.5.0.tgz",
       "integrity": "sha1-ms1whRxtXf3ZPZKC5e35SgP/RrU="
     },
-    "decamelize": {
-      "version": "1.2.0",
-      "resolved": "https://registry.npmjs.org/decamelize/-/decamelize-1.2.0.tgz",
-      "integrity": "sha1-9lNNFRSCabIDUue+4m9QH5oZEpA=",
-      "dev": true
-    },
-    "defs": {
-      "version": "1.1.1",
-      "resolved": "https://registry.npmjs.org/defs/-/defs-1.1.1.tgz",
-      "integrity": "sha1-siYJ8sehG6ej2xFoBcE5scr/qdI=",
-      "dev": true,
-      "requires": {
-        "alter": "0.2.0",
-        "ast-traverse": "0.1.1",
-        "breakable": "1.0.0",
-        "esprima-fb": "15001.1001.0-dev-harmony-fb",
-        "simple-fmt": "0.1.0",
-        "simple-is": "0.2.0",
-        "stringmap": "0.2.2",
-        "stringset": "0.2.1",
-        "tryor": "0.1.2",
-        "yargs": "3.27.0"
-      }
-    },
     "diff": {
       "version": "2.2.3",
       "resolved": "https://registry.npmjs.org/diff/-/diff-2.2.3.tgz",
       "integrity": "sha1-YOr9DSjukG5Oj/ClLBIpUhAzv5k=",
       "dev": true
     },
-    "esprima-fb": {
-      "version": "15001.1001.0-dev-harmony-fb",
-      "resolved": "https://registry.npmjs.org/esprima-fb/-/esprima-fb-15001.1001.0-dev-harmony-fb.tgz",
-      "integrity": "sha1-Q761fsJujPI3092LM+QlM1d/Jlk=",
-      "dev": true
-    },
     "find-line-column": {
       "version": "0.5.2",
       "resolved": "https://registry.npmjs.org/find-line-column/-/find-line-column-0.5.2.tgz",
       "integrity": "sha1-2wAjj/hoVRoYLnShA0FtKVqYyMo=",
       "dev": true
     },
-    "invert-kv": {
-      "version": "1.0.0",
-      "resolved": "https://registry.npmjs.org/invert-kv/-/invert-kv-1.0.0.tgz",
-      "integrity": "sha1-EEqOSqym09jNFXqO+L+rLXo//bY=",
-      "dev": true
-    },
-    "is-buffer": {
-      "version": "1.1.5",
-      "resolved": "https://registry.npmjs.org/is-buffer/-/is-buffer-1.1.5.tgz",
-      "integrity": "sha1-Hzsm72E7IUuIy8ojzGwB2Hlh7sw=",
-      "dev": true
-    },
-    "kind-of": {
-      "version": "3.2.2",
-      "resolved": "https://registry.npmjs.org/kind-of/-/kind-of-3.2.2.tgz",
-      "integrity": "sha1-MeohpzS6ubuw8yRm2JOupR5KPGQ=",
-      "dev": true,
-      "requires": {
-        "is-buffer": "1.1.5"
-      }
-    },
-    "lazy-cache": {
-      "version": "1.0.4",
-      "resolved": "https://registry.npmjs.org/lazy-cache/-/lazy-cache-1.0.4.tgz",
-      "integrity": "sha1-odePw6UEdMuAhF07O24dpJpEbo4=",
-      "dev": true
-    },
-    "lcid": {
-      "version": "1.0.0",
-      "resolved": "https://registry.npmjs.org/lcid/-/lcid-1.0.0.tgz",
-      "integrity": "sha1-MIrMr6C8SDo4Z7S28rlQYlHRuDU=",
-      "dev": true,
-      "requires": {
-        "invert-kv": "1.0.0"
-      }
-    },
-    "longest": {
-      "version": "1.0.1",
-      "resolved": "https://registry.npmjs.org/longest/-/longest-1.0.1.tgz",
-      "integrity": "sha1-MKCy2jj3N3DoKUoNIuZiXtd9AJc=",
-      "dev": true
-    },
     "minimist": {
       "version": "0.0.10",
       "resolved": "https://registry.npmjs.org/minimist/-/minimist-0.0.10.tgz",
@@ -184,30 +54,6 @@
         "wordwrap": "0.0.3"
       }
     },
-    "os-locale": {
-      "version": "1.4.0",
-      "resolved": "https://registry.npmjs.org/os-locale/-/os-locale-1.4.0.tgz",
-      "integrity": "sha1-IPnxeuKe00XoveWDsT0gCYA8FNk=",
-      "dev": true,
-      "requires": {
-        "lcid": "1.0.0"
-      }
-    },
-    "repeat-string": {
-      "version": "1.6.1",
-      "resolved": "https://registry.npmjs.org/repeat-string/-/repeat-string-1.6.1.tgz",
-      "integrity": "sha1-jcrkcOHIirwtYA//Sndihtp15jc=",
-      "dev": true
-    },
-    "right-align": {
-      "version": "0.1.3",
-      "resolved": "https://registry.npmjs.org/right-align/-/right-align-0.1.3.tgz",
-      "integrity": "sha1-YTObci/mo1FWiSENJOFMlhSGE+8=",
-      "dev": true,
-      "requires": {
-        "align-text": "0.1.4"
-      }
-    },
     "simple-fmt": {
       "version": "0.1.0",
       "resolved": "https://registry.npmjs.org/simple-fmt/-/simple-fmt-0.1.0.tgz",
@@ -243,36 +89,10 @@
       "resolved": "https://registry.npmjs.org/tryor/-/tryor-0.1.2.tgz",
       "integrity": "sha1-gUXkynyv9ArN48z5Rui4u3W0Fys="
     },
-    "window-size": {
-      "version": "0.1.4",
-      "resolved": "https://registry.npmjs.org/window-size/-/window-size-0.1.4.tgz",
-      "integrity": "sha1-+OGqHuWlPsW/FR/6CXQqatdpeHY=",
-      "dev": true
-    },
     "wordwrap": {
       "version": "0.0.3",
       "resolved": "https://registry.npmjs.org/wordwrap/-/wordwrap-0.0.3.tgz",
       "integrity": "sha1-o9XabNXAvAAI03I0u68b7WMFkQc="
-    },
-    "y18n": {
-      "version": "3.2.1",
-      "resolved": "https://registry.npmjs.org/y18n/-/y18n-3.2.1.tgz",
-      "integrity": "sha1-bRX7qITAhnnA136I53WegR4H+kE=",
-      "dev": true
-    },
-    "yargs": {
-      "version": "3.27.0",
-      "resolved": "https://registry.npmjs.org/yargs/-/yargs-3.27.0.tgz",
-      "integrity": "sha1-ISBUaTFuk5Ex1Z8toMbX+YIh6kA=",
-      "dev": true,
-      "requires": {
-        "camelcase": "1.2.1",
-        "cliui": "2.1.0",
-        "decamelize": "1.2.0",
-        "os-locale": "1.4.0",
-        "window-size": "0.1.4",
-        "y18n": "3.2.1"
-      }
     }
   }
 }
diff --git a/package.json b/package.json
index 3b512c3..ca874b2 100644
--- a/package.json
+++ b/package.json
@@ -2,7 +2,7 @@
   "name": "ng-annotate-patched",
   "version": "1.6.0",
   "description": "add, remove and rebuild angularjs dependency injection annotations",
-  "main": "build/es5/ng-annotate-main.js",
+  "main": "ng-annotate-main.js",
   "repository": {
     "type": "git",
     "url": "https://github.com/bluetech/ng-annotate-patched.git"
@@ -22,7 +22,6 @@
   },
   "devDependencies": {
     "coffee-script": "^1.10.0",
-    "defs": "^1.1.1",
     "diff": "^2.2.1",
     "find-line-column": "^0.5.2"
   },
@@ -38,9 +37,9 @@
     "transformation"
   ],
   "scripts": {
-    "test": "node --harmony run-tests"
+    "test": "node run-tests"
   },
-  "bin": "./build/es5/ng-annotate",
+  "bin": "./ng-annotate",
   "author": "Olov Lassus <olov.lassus@gmail.com>",
   "license": "MIT"
 }