title: Unable to install bcrypt on Digital Ocean node.js instance
body: <p>I'm trying to use bcrypt for hashing passwords in a MEAN stack application. I'm hosting this on and Ubuntu 14 instance on Digital ocean and though my applicaiton runs fine locally, I'm getting a 502 bad gateway error from the server and I've narrowed the cause down to bcrypt. </p>
  
  <p>I'm trying to install bcrypt on to a Digital Ocean node.js instance and get the following error:</p>
  
  <pre><code>root@mydomain:~# npm install -g bcrypt
  -
  &gt; bcrypt@1.0.1 install /usr/lib/node_modules/bcrypt
  &gt; node-pre-gyp install --fallback-to-build
  
  node-pre-gyp ERR! Tried to download: https://github.com/kelektiv/node.bcrypt.js/releases/download/v1.0.1/bcrypt_lib-v1.0.1-node-v46-linux-x64.tar.gz 
  node-pre-gyp ERR! Pre-built binaries not found for bcrypt@1.0.1 and node@4.4.3 (node-v46 ABI) (falling back to source compile with node-gyp) 
  gyp WARN EACCES user "root" does not have permission to access the dev dir "/root/.node-gyp/4.4.3"
  gyp WARN EACCES attempting to reinstall using temporary dev dir "/usr/lib/node_modules/bcrypt/.node-gyp"
  make: Entering directory `/usr/lib/node_modules/bcrypt/build'
  make: *** No rule to make target `../.node-gyp/4.4.3/include/node/common.gypi', needed by `Makefile'.  Stop.
  make: Leaving directory `/usr/lib/node_modules/bcrypt/build'
  gyp ERR! build error 
  gyp ERR! stack Error: `make` failed with exit code: 2
  gyp ERR! stack     at ChildProcess.onExit (/usr/lib/node_modules/npm/node_modules/node-gyp/lib/build.js:276:23)
  gyp ERR! stack     at emitTwo (events.js:87:13)
  gyp ERR! stack     at ChildProcess.emit (events.js:172:7)
  gyp ERR! stack     at Process.ChildProcess._handle.onexit (internal/child_process.js:200:12)
  gyp ERR! System Linux 3.13.0-85-generic
  gyp ERR! command "/usr/bin/nodejs" "/usr/lib/node_modules/npm/node_modules/node-gyp/bin/node-gyp.js" "build" "--fallback-to-build" "--module=/usr/lib/node_modules/bcrypt/lib/binding/bcrypt_lib.node" "--module_name=bcrypt_lib" "--module_path=/usr/lib/node_modules/bcrypt/lib/binding"
  gyp ERR! cwd /usr/lib/node_modules/bcrypt
  gyp ERR! node -v v4.4.3
  gyp ERR! node-gyp -v v3.3.1
  gyp ERR! not ok 
  node-pre-gyp ERR! build error 
  node-pre-gyp ERR! stack Error: Failed to execute '/usr/bin/nodejs /usr/lib/node_modules/npm/node_modules/node-gyp/bin/node-gyp.js build --fallback-to-build --module=/usr/lib/node_modules/bcrypt/lib/binding/bcrypt_lib.node --module_name=bcrypt_lib --module_path=/usr/lib/node_modules/bcrypt/lib/binding' (1)
  node-pre-gyp ERR! stack     at ChildProcess.&lt;anonymous&gt; (/usr/lib/node_modules/bcrypt/node_modules/node-pre-gyp/lib/util/compile.js:83:29)
  node-pre-gyp ERR! stack     at emitTwo (events.js:87:13)
  node-pre-gyp ERR! stack     at ChildProcess.emit (events.js:172:7)
  node-pre-gyp ERR! stack     at maybeClose (internal/child_process.js:827:16)
  node-pre-gyp ERR! stack     at Process.ChildProcess._handle.onexit (internal/child_process.js:211:5)
  node-pre-gyp ERR! System Linux 3.13.0-85-generic
  node-pre-gyp ERR! command "/usr/bin/nodejs" "/usr/lib/node_modules/bcrypt/node_modules/.bin/node-pre-gyp" "install" "--fallback-to-build"
  node-pre-gyp ERR! cwd /usr/lib/node_modules/bcrypt
  node-pre-gyp ERR! node -v v4.4.3
  node-pre-gyp ERR! node-pre-gyp -v v0.6.30
  node-pre-gyp ERR! not ok 
  Failed to execute '/usr/bin/nodejs /usr/lib/node_modules/npm/node_modules/node-gyp/bin/node-gyp.js build --fallback-to-build --module=/usr/lib/node_modules/bcrypt/lib/binding/bcrypt_lib.node --module_name=bcrypt_lib --module_path=/usr/lib/node_modules/bcrypt/lib/binding' (1)
  npm ERR! Linux 3.13.0-85-generic
  npm ERR! argv "/usr/bin/nodejs" "/usr/bin/npm" "install" "-g" "bcrypt"
  npm ERR! node v4.4.3
  npm ERR! npm  v2.15.1
  npm ERR! code ELIFECYCLE
  
  npm ERR! bcrypt@1.0.1 install: `node-pre-gyp install --fallback-to-build`
  npm ERR! Exit status 1
  npm ERR! 
  npm ERR! Failed at the bcrypt@1.0.1 install script 'node-pre-gyp install --fallback-to-build'.
  npm ERR! This is most likely a problem with the bcrypt package,
  npm ERR! not with npm itself.
  npm ERR! Tell the author that this fails on your system:
  npm ERR!     node-pre-gyp install --fallback-to-build
  npm ERR! You can get information on how to open an issue for this project with:
  npm ERR!     npm bugs bcrypt
  npm ERR! Or if that isn't available, you can get their info via:
  npm ERR! 
  npm ERR!     npm owner ls bcrypt
  npm ERR! There is likely additional logging output above.
  
  npm ERR! Please include the following file with any support request:
  npm ERR!     /root/npm-debug.log
  </code></pre>