turnkey

Short definition from Wiktionary

Adjective

1. 1
   Ready to use without further assembly or test; supplied in a state that is ready to turn on and operate (typically refers to an assembly that is outsourced for manufacture).

Noun

1. 1
   A system that is supplied ready to switch on and operate.
2. 2
   A warder or jailer; a keeper of the keys in a prison.

Verb

1. 1
   To supply a turnkey product; to supply something fully assembled and ready to use.