Our V4 API version is currently available as Beta! It means that V3 will still be supported and remain unchanged for now, but be aware that the following changes are in V4:
/projects/:search (use: /projects?search=x)iid filter has been removed from projects/:id/issuesprojects/:id/merge_requests?iid[]=x&iid[]=y array filter has been renamed to iidsprojects/merge_request/:id have been removed (use: projects/merge_requests/:id)expires_atprojects/:id/keys have been removed (use projects/:id/deploy_keys)