diff --git a/.gitignore b/.gitignore
index c5bbe22..c8ba63b 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,4 +1,5 @@
 coverage
 test/home/.config
+test/home/builds
 .nyc_output
 node_modules/
diff --git a/README.md b/README.md
index 0faaa07..2a5a258 100644
--- a/README.md
+++ b/README.md
@@ -39,6 +39,8 @@ gcr - a gitlab ci runner
       -s, --strictSSL             enable/disable strict ssl
       -n, --npm                   run npm install/test if no commands are present
       -k, --keypath <path>        specify path to rsa key
+      -s, --shell <path>          specify path to shell e.g. /bin/bash
+      -sf, --shellFlag <flag>     set the flag to run commands on your shell e.g. -c
       -C, --sslcert <path>        enable/disable strict ssl
       -K, --sslkey <path>         run npm install/test if no commands are present
       -A, --cacert <path>         specify path to rsa key
diff --git a/bin/cmd.js b/bin/cmd.js
index 130d498..3f59c6e 100755
--- a/bin/cmd.js
+++ b/bin/cmd.js
@@ -22,6 +22,8 @@ var gcr = require('../lib/gcr')
                 , strictSSL: Boolean
                 , timeout: Number
                 , keypath: path
+                , shell: path
+                , shellFlag: String
                 , sslcert: path
                 , sslkey: path
                 , cacert: path
@@ -35,6 +37,8 @@ var gcr = require('../lib/gcr')
                 , s: ['--strictSSL']
                 , T: ['--timeout']
                 , k: ['--keypath']
+                , s: ['--shell']
+                , f: ['--shellFlag']
                 , C: ['--sslcert']
                 , K: ['--sslkey']
                 , A: ['--cacert']
diff --git a/bin/usage.txt b/bin/usage.txt
index be53180..5c97c0d 100644
--- a/bin/usage.txt
+++ b/bin/usage.txt
@@ -16,6 +16,8 @@ gcr - a gitlab ci runner
       -s, --strictSSL             enable/disable strict ssl
       -n, --npm                   run npm install/test if no commands are present
       -k, --keypath <path>        specify path to rsa key
+      -s, --shell <path>          specify path to shell e.g. /bin/bash
+      -sf, --shellFlag <flag>     set the flag to run commands on your shell e.g. -c
       -C, --sslcert <path>        enable/disable strict ssl
       -K, --sslkey <path>         run npm install/test if no commands are present
       -A, --cacert <path>         specify path to rsa key
diff --git a/lib/build.js b/lib/build.js
index 36592af..fc4314f 100644
--- a/lib/build.js
+++ b/lib/build.js
@@ -188,7 +188,12 @@ Build.prototype.runCommand = function(cmd, dir, cb) {
   log.verbose('[builder]', 'cmd', cmd)
   this.append(`\n${cmd}\n`)
 
-  const child = spawn('/bin/sh', ['-c', fixedCmd.join(' ')], opts)
+  const child = spawn(
+    gcr.config.get('shell')
+    , [gcr.config.get('shellFlag')
+    , fixedCmd.join(' ')]
+    , opts
+  )
   var timedout = false
   var timer = setTimeout(() => {
     timedout = true
diff --git a/lib/config.default.js b/lib/config.default.js
index af02855..75c8b9a 100644
--- a/lib/config.default.js
+++ b/lib/config.default.js
@@ -24,5 +24,16 @@ module.exports = function(parsed) {
   o.strictSSL = parsed.hasOwnProperty('strictSSL')
               ? parsed.strictSSL
               : true
+
+  o.shell = parsed.shell
+    ? parsed.shell
+    : isWin
+    ? 'C:\\Windows\\System32\\cmd.exe'
+    : '/bin/bash'
+  o.shellFlag = parsed.shellFlag
+    ? parsed.shellFlag
+    : isWin
+    ? '/C'
+    : '-c'
   return o
 }
diff --git a/lib/gcr.js b/lib/gcr.js
index 20997b9..a2038e6 100644
--- a/lib/gcr.js
+++ b/lib/gcr.js
@@ -57,6 +57,12 @@ gcr.load = function(opts, cb) {
     if (opts.keypath) {
       nconf.set('keypath', opts.keypath)
     }
+    if (opts.shell) {
+      nconf.set('shell', opts.shell)
+    }
+    if (opts.shellFlag) {
+      nconf.set('shellFlag', opts.shellFlag)
+    }
     if (opts.sslcert) {
       nconf.set('sslcert', opts.sslcert)
     }
diff --git a/test/gcr.js b/test/gcr.js
index c4d5be3..64c90cf 100644
--- a/test/gcr.js
+++ b/test/gcr.js
@@ -29,8 +29,10 @@ test('setup', (t) => {
 })
 
 test('gcr', (t) => {
+  var home = require('os-homedir')()
+
   t.type(gcr, EE)
-  t.equal(gcr.root, path.join(HOME, '.config'), 'gcr.root is correct')
+  t.equal(gcr.root, path.join(home, '.config'), 'gcr.root is correct')
   t.equal(gcr.loaded, false, 'gcr.loaded is false')
   t.equal(gcr.version, require('../package').version, 'gcr.version is correct')
   t.ok(gcr.hasOwnProperty('utils'), 'hasOwnProperty(utils)')
@@ -59,6 +61,19 @@ test('load', (t) => {
   })
 })
 
+test('shell selection', (t) => {
+  t.plan(2)
+  t.match(gcr.config.get('shell')
+    , /cmd\.exe$|\/bash$/
+    , 'Shell is either cmd.exe or /bin/bash'
+  )
+
+  t.match(gcr.config.get('shellFlag')
+    , /[-/][cC]/
+    , 'Shell Flag is either -c or /C'
+  )
+})
+
 test('build and run with clone', (t) => {
   t.plan(11)
   const build = Build({
@@ -79,7 +94,7 @@ test('build and run with clone', (t) => {
   t.ok(build.hasOwnProperty('opts'), 'hasOwnProperty(opts)')
   t.ok(build.hasOwnProperty('output'), 'hasOwnProperty(output)')
   t.ok(build.hasOwnProperty('projectDir'), 'hasOwnProperty(projectDir)')
-  t.equal(build.projectDir, '/tmp/gcr-builds/project-1')
+  t.equal(build.projectDir, path.join('/', 'tmp', 'gcr-builds', 'project-1'))
   t.equal(build.state, 'waiting')
 
   const orig = build.update
@@ -117,7 +132,7 @@ test('build and run with fetch', (t) => {
   t.ok(build.hasOwnProperty('opts'), 'hasOwnProperty(opts)')
   t.ok(build.hasOwnProperty('output'), 'hasOwnProperty(output)')
   t.ok(build.hasOwnProperty('projectDir'), 'hasOwnProperty(projectDir)')
-  t.equal(build.projectDir, '/tmp/gcr-builds/project-2')
+  t.equal(build.projectDir, path.join('/', 'tmp', 'gcr-builds', 'project-2'))
   t.equal(build.state, 'waiting')
 
   const updateOrig = gcr.client.updateBuild