diff --git a/lib/index-api.js b/lib/index-api.js
index 7f0ad9a95..06fbfa3d1 100644
--- a/lib/index-api.js
+++ b/lib/index-api.js
@@ -15,9 +15,10 @@ let validate_name = Middleware.validate_name;
 let validate_pkg = Middleware.validate_package;
 
 module.exports = function(config, auth, storage) {
-  let app = express.Router();
-  let can = Middleware.allow(auth);
-  let notify = Notify.notify;
+  /* eslint new-cap:off */
+  const app = express.Router();
+  const can = Middleware.allow(auth);
+  const notify = Notify.notify;
 
   // validate all of these params as a package name
   // this might be too harsh, so ask if it causes trouble
@@ -124,6 +125,23 @@ module.exports = function(config, auth, storage) {
     */
     const respShouldBeArray = req.path.endsWith('/since');
     res.set('Date', 'Mon, 10 Oct 1983 00:12:48 GMT');
+    const check_finish = function() {
+      if (!received_end) {
+        return;
+      }
+      if (processing_pkgs) {
+        return;
+      }
+      if (response_finished) {
+        return;
+      }
+      response_finished = true;
+      if (respShouldBeArray) {
+        res.end(']\n');
+      } else {
+        res.end('}\n');
+      }
+    };
 
     if (respShouldBeArray) {
       res.write('[');
@@ -172,19 +190,6 @@ module.exports = function(config, auth, storage) {
       received_end = true;
       check_finish();
     });
-
-    function check_finish() {
-      if (!received_end) return;
-      if (processing_pkgs) return;
-      if (response_finished) return;
-
-      response_finished = true;
-      if (respShouldBeArray) {
-        res.end(']\n');
-      } else {
-        res.end('}\n');
-      }
-    }
   });
 
   // placeholder 'cause npm require to be authenticated to publish
@@ -216,13 +221,6 @@ module.exports = function(config, auth, storage) {
         token: token,
       });
     } else {
-      if (typeof(req.body.name) !== 'string' || typeof(req.body.password) !== 'string') {
-        if (typeof(req.body.password_sha)) {
-          return next( Error[422]('your npm version is outdated\nPlease update to npm@1.4.5 or greater.\nSee https://github.com/rlidwka/sinopia/issues/93 for details.') );
-        } else {
-          return next( Error[422]('user/password is not found in request (npm issue?)') );
-        }
-      }
       auth.add_user(req.body.name, req.body.password, function(err, user) {
         if (err) {
           if (err.status >= 400 && err.status < 500) {
@@ -252,8 +250,10 @@ module.exports = function(config, auth, storage) {
     });
   });
 
-  function tag_package_version(req, res, next) {
-    if (typeof(req.body) !== 'string') return next('route');
+  const tag_package_version = function(req, res, next) {
+    if (typeof(req.body) !== 'string') {
+      return next('route');
+    }
 
     let tags = {};
     tags[req.params.tag] = req.body;
@@ -262,7 +262,7 @@ module.exports = function(config, auth, storage) {
       res.status(201);
       return next({ok: 'package tagged'});
     });
-  }
+  };
 
   // tagging a package
   app.put('/:package/:tag',
@@ -292,8 +292,7 @@ module.exports = function(config, auth, storage) {
     });
   });
 
-  app.post('/-/package/:package/dist-tags',
-      can('publish'), media('application/json'), expect_json,
+  app.post('/-/package/:package/dist-tags', can('publish'), media('application/json'), expect_json,
       function(req, res, next) {
     storage.merge_tags(req.params.package, req.body, function(err) {
       if (err) return next(err);
@@ -302,8 +301,7 @@ module.exports = function(config, auth, storage) {
     });
   });
 
-  app.put('/-/package/:package/dist-tags',
-      can('publish'), media('application/json'), expect_json,
+  app.put('/-/package/:package/dist-tags', can('publish'), media('application/json'), expect_json,
       function(req, res, next) {
     storage.replace_tags(req.params.package, req.body, function(err) {
       if (err) return next(err);
@@ -312,8 +310,7 @@ module.exports = function(config, auth, storage) {
     });
   });
 
-  app.delete('/-/package/:package/dist-tags',
-      can('publish'), media('application/json'),
+  app.delete('/-/package/:package/dist-tags', can('publish'), media('application/json'),
       function(req, res, next) {
     storage.replace_tags(req.params.package, {}, function(err) {
       if (err) return next(err);
@@ -325,6 +322,79 @@ module.exports = function(config, auth, storage) {
   // publishing a package
   app.put('/:package/:_rev?/:revision?', can('publish'), media('application/json'), expect_json, function(req, res, next) {
     let name = req.params.package;
+    let metadata;
+    const create_tarball = function(filename, data, cb) {
+      let stream = storage.add_tarball(name, filename);
+      stream.on('error', function(err) {
+        cb(err);
+      });
+      stream.on('success', function() {
+        cb();
+      });
+
+      // this is dumb and memory-consuming, but what choices do we have?
+      stream.end(new Buffer(data.data, 'base64'));
+      stream.done();
+    };
+
+    const create_version = function(version, data, cb) {
+      storage.add_version(name, version, data, null, cb);
+    };
+
+    const add_tags = function(tags, cb) {
+      storage.merge_tags(name, tags, cb);
+    };
+
+    const after_change = function(err, ok_message) {
+      // old npm behaviour
+      if (metadata._attachments == null) {
+        if (err) return next(err);
+        res.status(201);
+        return next({ok: ok_message, success: true});
+      }
+
+      // npm-registry-client 0.3+ embeds tarball into the json upload
+      // https://github.com/isaacs/npm-registry-client/commit/e9fbeb8b67f249394f735c74ef11fe4720d46ca0
+      // issue https://github.com/rlidwka/sinopia/issues/31, dealing with it here:
+
+      if (typeof(metadata._attachments) !== 'object'
+      || Object.keys(metadata._attachments).length !== 1
+      || typeof(metadata.versions) !== 'object'
+      || Object.keys(metadata.versions).length !== 1) {
+        // npm is doing something strange again
+        // if this happens in normal circumstances, report it as a bug
+        return next( Error[400]('unsupported registry call') );
+      }
+
+      if (err && err.status != 409) {
+        return next(err);
+      }
+
+      // at this point document is either created or existed before
+      const t1 = Object.keys(metadata._attachments)[0];
+      create_tarball(Path.basename(t1), metadata._attachments[t1], function(err) {
+        if (err) {
+          return next(err);
+        }
+
+        const t2 = Object.keys(metadata.versions)[0];
+        metadata.versions[t2].readme = metadata.readme != null ? String(metadata.readme) : '';
+        create_version(t2, metadata.versions[t2], function(err) {
+          if (err) {
+             return next(err);
+          }
+
+          add_tags(metadata['dist-tags'], function(err) {
+            if (err) {
+              return next(err);
+            }
+            notify(metadata, config);
+            res.status(201);
+            return next({ok: ok_message, success: true});
+          });
+        });
+      });
+    };
 
     if (Object.keys(req.body).length == 1 && Utils.is_object(req.body.users)) {
       // 501 status is more meaningful, but npm doesn't show error message for 5xx
@@ -332,7 +402,7 @@ module.exports = function(config, auth, storage) {
     }
 
     try {
-      var metadata = Utils.validate_metadata(req.body, name);
+      metadata = Utils.validate_metadata(req.body, name);
     } catch(err) {
       return next( Error[422]('bad incoming package data') );
     }
@@ -346,77 +416,14 @@ module.exports = function(config, auth, storage) {
         after_change(err, 'created new package');
       });
     }
-
-    function after_change(err, ok_message) {
-      // old npm behaviour
-      if (metadata._attachments == null) {
-        if (err) return next(err);
-        res.status(201);
-        return next({ok: ok_message, success: true});
-      }
-
-      // npm-registry-client 0.3+ embeds tarball into the json upload
-      // https://github.com/isaacs/npm-registry-client/commit/e9fbeb8b67f249394f735c74ef11fe4720d46ca0
-      // issue #31, dealing with it here:
-
-      if (typeof(metadata._attachments) !== 'object'
-      || Object.keys(metadata._attachments).length !== 1
-      || typeof(metadata.versions) !== 'object'
-      || Object.keys(metadata.versions).length !== 1) {
-        // npm is doing something strange again
-        // if this happens in normal circumstances, report it as a bug
-        return next( Error[400]('unsupported registry call') );
-      }
-
-      if (err && err.status != 409) return next(err);
-
-      // at this point document is either created or existed before
-      let t1 = Object.keys(metadata._attachments)[0];
-      create_tarball(Path.basename(t1), metadata._attachments[t1], function(err) {
-        if (err) return next(err);
-
-        let t2 = Object.keys(metadata.versions)[0];
-        metadata.versions[t2].readme = metadata.readme != null ? String(metadata.readme) : '';
-        create_version(t2, metadata.versions[t2], function(err) {
-          if (err) return next(err);
-
-          add_tags(metadata['dist-tags'], function(err) {
-            if (err) return next(err);
-            notify(metadata, config);
-            res.status(201);
-            return next({ok: ok_message, success: true});
-          });
-        });
-      });
-    }
-
-    function create_tarball(filename, data, cb) {
-      let stream = storage.add_tarball(name, filename);
-      stream.on('error', function(err) {
-        cb(err);
-      });
-      stream.on('success', function() {
-        cb();
-      });
-
-      // this is dumb and memory-consuming, but what choices do we have?
-      stream.end(new Buffer(data.data, 'base64'));
-      stream.done();
-    }
-
-    function create_version(version, data, cb) {
-      storage.add_version(name, version, data, null, cb);
-    }
-
-    function add_tags(tags, cb) {
-      storage.merge_tags(name, tags, cb);
-    }
-  });
+});
 
   // unpublishing an entire package
   app.delete('/:package/-rev/*', can('publish'), function(req, res, next) {
     storage.remove_package(req.params.package, function(err) {
-      if (err) return next(err);
+      if (err) {
+        return next(err);
+      }
       res.status(201);
       return next({ok: 'package removed'});
     });
@@ -425,7 +432,9 @@ module.exports = function(config, auth, storage) {
   // removing a tarball
   app.delete('/:package/-/:filename/-rev/:revision', can('publish'), function(req, res, next) {
     storage.remove_tarball(req.params.package, req.params.filename, req.params.revision, function(err) {
-      if (err) return next(err);
+      if (err) {
+        return next(err);
+      }
       res.status(201);
       return next({ok: 'tarball removed'});
     });
@@ -433,9 +442,8 @@ module.exports = function(config, auth, storage) {
 
   // uploading package tarball
   app.put('/:package/-/:filename/*', can('publish'), media('application/octet-stream'), function(req, res, next) {
-    let name = req.params.package;
-
-    let stream = storage.add_tarball(name, req.params.filename);
+    const name = req.params.package;
+    const stream = storage.add_tarball(name, req.params.filename);
     req.pipe(stream);
 
     // checking if end event came before closing
diff --git a/lib/index-web.js b/lib/index-web.js
index 3c2c92644..91866f064 100644
--- a/lib/index-web.js
+++ b/lib/index-web.js
@@ -14,6 +14,7 @@ let validate_name = Middleware.validate_name;
 let validate_pkg = Middleware.validate_package;
 
 module.exports = function(config, auth, storage) {
+  /* eslint new-cap:off */
   let app = express.Router();
   let can = Middleware.allow(auth);
 
diff --git a/lib/local-fs.js b/lib/local-fs.js
index 2d1908236..6a5de6f67 100644
--- a/lib/local-fs.js
+++ b/lib/local-fs.js
@@ -1,3 +1,5 @@
+/* eslint prefer-spread: "off" */
+
 'use strict';
 
 const fs = require('fs');
@@ -5,24 +7,25 @@ const Error = require('http-errors');
 const mkdirp = require('mkdirp');
 const Path = require('path');
 const MyStreams = require('./streams');
+const locker = require('./file-locking');
 
-function FSError(code) {
-  let err = Error(code);
+const fSError = function(code) {
+  const err = Error(code);
   err.code = code;
   return err;
-}
+};
 
-let locker = require('./file-locking');
+const tempFile = function(str) {
+  return `${str}.tmp${String(Math.random()).substr(2)}`;
+};
 
-function tempFile(str) {
-  return str + '.tmp' + String(Math.random()).substr(2);
-}
-
-function renameTmp(src, dst, _cb) {
-  function cb(err) {
-    if (err) fs.unlink(src, function() {});
+const renameTmp = function(src, dst, _cb) {
+   const cb = function(err) {
+    if (err) {
+      fs.unlink(src, function() {});
+    }
     _cb(err);
-  }
+  };
 
   if (process.platform !== 'win32') {
     return fs.rename(src, dst, cb);
@@ -33,11 +36,13 @@ function renameTmp(src, dst, _cb) {
   let tmp = tempFile(dst);
   fs.rename(dst, tmp, function(err) {
     fs.rename(src, dst, cb);
-    if (!err) fs.unlink(tmp, () => {});
+    if (!err) {
+      fs.unlink(tmp, () => {});
+    }
   });
-}
+};
 
-function write(dest, data, cb) {
+const write = function(dest, data, cb) {
   let safe_write = function(cb) {
     let tmpname = tempFile(dest);
     fs.writeFile(tmpname, data, function(err) {
@@ -56,18 +61,19 @@ function write(dest, data, cb) {
       cb(err);
     }
   });
-}
-
-function write_stream(name) {
-  let stream = MyStreams.uploadTarballStream();
+};
 
+const write_stream = function(name) {
+  const stream = MyStreams.uploadTarballStream();
   let _ended = 0;
   stream.on('end', function() {
     _ended = 1;
   });
 
   fs.exists(name, function(exists) {
-    if (exists) return stream.emit('error', FSError('EEXISTS'));
+    if (exists) {
+      return stream.emit('error', fSError('EEXISTS'));
+    }
 
     let tmpname = name + '.tmp-'+String(Math.random()).replace(/^0\./, '');
     let file = fs.createWriteStream(tmpname);
@@ -75,7 +81,7 @@ function write_stream(name) {
     stream.pipe(file);
 
     stream.done = function() {
-      function onend() {
+      const onend = function() {
         file.on('close', function() {
           renameTmp(tmpname, name, function(err) {
             if (err) {
@@ -86,7 +92,7 @@ function write_stream(name) {
           });
         });
         file.destroySoon();
-      }
+      };
       if (_ended) {
         onend();
       } else {
@@ -112,9 +118,9 @@ function write_stream(name) {
     });
   });
   return stream;
-}
+};
 
-function read_stream(name, stream, callback) {
+const read_stream = function(name, stream, callback) {
   let rstream = fs.createReadStream(name);
   rstream.on('error', function(err) {
     stream.emit('error', err);
@@ -133,31 +139,37 @@ function read_stream(name, stream, callback) {
     rstream.close();
   };
   return stream;
-}
+};
 
-function create(name, contents, callback) {
+const create = function(name, contents, callback) {
   fs.exists(name, function(exists) {
-    if (exists) return callback( FSError('EEXISTS') );
+    if (exists) {
+      return callback( fSError('EEXISTS') );
+    }
     write(name, contents, callback);
   });
-}
+};
 
-function update(name, contents, callback) {
+const update = function(name, contents, callback) {
   fs.exists(name, function(exists) {
-    if (!exists) return callback( FSError('ENOENT') );
+    if (!exists) {
+      return callback( fSError('ENOENT') );
+    }
     write(name, contents, callback);
   });
-}
+};
 
-function read(name, callback) {
+const read = function(name, callback) {
   fs.readFile(name, callback);
-}
+};
 
 module.exports.read = read;
 
 module.exports.read_json = function(name, cb) {
   read(name, function(err, res) {
-    if (err) return cb(err);
+    if (err) {
+      return cb(err);
+    }
 
     let args = [];
     try {
@@ -171,14 +183,18 @@ module.exports.read_json = function(name, cb) {
 
 module.exports.lock_and_read = function(name, cb) {
   locker.readFile(name, {lock: true}, function(err, res) {
-    if (err) return cb(err);
+    if (err) {
+      return cb(err);
+    }
     return cb(null, res);
   });
 };
 
 module.exports.lock_and_read_json = function(name, cb) {
   locker.readFile(name, {lock: true, parse: true}, function(err, res) {
-    if (err) return cb(err);
+    if (err) {
+      return cb(err);
+    }
     return cb(null, res);
   });
 };
diff --git a/package.json b/package.json
index 8823b44f5..72c296b10 100644
--- a/package.json
+++ b/package.json
@@ -81,7 +81,8 @@
     "build-docker:rpi": "docker build -f Dockerfile.rpi -t verdaccio:rpi ."
   },
   "engines": {
-    "node": ">=4.6.1"
+    "node": ">=4.6.1",
+    "npm" : ">=2.15.9" 
   },
   "preferGlobal": true,
   "publishConfig": {