diff --git a/ci-services/codeship.js b/ci-services/codeship.js
new file mode 100644
index 00000000..2a3271d5
--- /dev/null
+++ b/ci-services/codeship.js
@@ -0,0 +1,95 @@
+const relative = require('require-relative')
+const gitHelpers = require('../lib/git-helpers')
+
+const env = process.env
+const pkg = relative('./package.json')
+
+/**
+ * Generates repoSlug from user set `GH_ORG` env var and Codeship set
+ * `CI_REPO_NAME`. Fails back to extracting from `package.json`.repository.url
+ */
+function getRepoSlug () {
+  if (env.GH_ORG) {
+    return `${env.GH_ORG}/${env.CI_REPO_NAME}`
+  }
+  let re = /github\.com[:/]([^/]+\/[^/\.]+)/g // eslint-disable-line no-useless-escape
+  let result
+  if (typeof pkg.repository === 'string') {
+    result = re.exec(pkg.repository)
+  } else if (typeof pkg.repository.url === 'string') {
+    result = re.exec(pkg.repository.url)
+  }
+  if (result && result[1]) {
+    return result[1]
+  }
+  console.warn('Failed to extract repoSlug from package.json, pushes will probably fail.')
+  console.warn('Set repository.url with the repo GitHub url in package.json.')
+  return env.CI_REPO_NAME
+}
+
+/**
+ * Should update the `package-lock.json`
+ */
+function shouldUpdate () {
+  let re = /^(chore|fix)\(package\): update [^ ]+ to version.*$/mi
+  return re.test(env.CI_COMMIT_MESSAGE)
+}
+
+module.exports = {
+  // The GitHub repo slug
+  repoSlug: getRepoSlug(),
+  // The name of the current branch
+  branchName: env.CI_BRANCH,
+  // Is this the first push on this branch
+  // i.e. the Greenkeeper commit
+  firstPush: shouldUpdate(),
+  // Is this a regular build (use tag: ^greenkeeper/)
+  correctBuild: shouldUpdate(),
+  // Should the lockfile be uploaded from this build (use tag: ^greenkeeper/)
+  uploadBuild: shouldUpdate(),
+  commitNum: gitHelpers.getNumberOfCommitsOnBranch(env.CI_BRANCH),
+  realFirstPush: gitHelpers.getNumberOfCommitsOnBranch(env.CI_BRANCH) === 1
+}
+
+/*
+Example `codeship-steps.yml`:
+```yml
+- name: "Greenkeeper: install greenkeeper-lockfile"
+  tag: ^greenkeeper/
+  service: app
+  command: npm i -g greenkeeper-lockfile
+- name: "Greenkeeper: update lockfile"
+  tag: ^greenkeeper/
+  service: app
+  command: greenkeeper-lockfile-update
+- name: Test
+  service: app
+  command: npm run codeship-test
+- name: "Greenkeeper: pushing lockfile"
+  tag: ^greenkeeper/
+  service: app
+  command: greenkeeper-lockfile-upload
+```
+
+`repository` key in `package.json` or GH_ORG with the org name is required, as there's no way to
+get it from the ENV vars that Codeship sets.
+`package.json`:
+```
+{
+  ...
+  "repository": "https://github.com/org/repo.git"
+  },
+  ...
+}
+```
+```
+{
+  ...
+  "repository": {
+    "type": "git",
+    "url": "https://github.com/org/repo.git"
+  },
+  ...
+}
+```
+*/
diff --git a/ci-services/tests.js b/ci-services/tests.js
index 65d33724..c223a7da 100644
--- a/ci-services/tests.js
+++ b/ci-services/tests.js
@@ -8,5 +8,6 @@ module.exports = {
   jenkins: () => env.JENKINS_URL !== undefined,
   travis: () => env.TRAVIS === 'true',
   wercker: () => env.WERCKER === 'true',
+  codeship: () => env.CI_NAME === 'codeship',
   bitrise: () => env.CI === 'true' && env.BITRISE_BUILD_NUMBER !== ''
 }