The World Federation One Stop Fiqh

Ruling 2186

It is not allowed to give on hire a minor (ṣaghīr) who does not have a guardian without authorisation from a jurist (mujtahid).3 As for someone who does not have access to a jurist, he can obtain authorisation from a dutiful (ʿādil) believer and give the child on hire.

3 A mujtahid is a person who has attained the level of ijtihād, qualifying him to be an authority in Islamic law. Ijtihād is the process of deriving Islamic laws from authentic sources.