All of Nerve's smart contracts are non-custodial - the developers do not have access to your funds.
The contracts have been audited by Certik; you can view the results of the audit here.
The contracts are in the process of being put under a 3/5 multisig for enhanced security. The five signatories are:
AureliusBTC, core developer
Socrates0x, core developer
Dovey Wan, Primitive Ventures
Dan Matuszewski, CMS Holdings
Arthur Cheong, DeFiance Capital