Bitcoin Multi-Sig Wallet Engineer (Freelance, PSBT/Descriptor Focus)

Evoke Solutions is the UK's first Bitcoin treasury consultancy for HNWIs and SMEs. We deliver secure, non-custodial, multi sig wallet setups with inheritance, governance, and risk controls baked in.

We're now building a simple interface to abstract away technical complexity for clients. Think: 2 of 3 wallet builder + Trezor integration + recovery test flow + PDF governance export.

We need a Bitcoin native engineer with real PSBT experience, who can help us build the first version of this product fast, clean, and secure.

• 2 of 3 wallet creation flow (with descriptors + address validation)
• Hardware wallet integration (Trezor via WebUSB or HWI)
• PSBT signing coordination (offline + online flows)
• Recovery simulation and signing UX
• Exportable PDF of wallet structure & governance model
• Optional lightweight admin dashboard to track setups

• BitcoinJS, Specter, Sparrow or Electrum experience
• PSBTs, Miniscript, or descriptor based wallet design
• Familiarity with multi sig coordination and hardware signing
• Clean UX thinking - we're not trying to build a bloated dashboard
• Bonus: experience with similar wallet projects

• Fee Range: £8,000 - £14,000 ($10,000 - $18,000 USD)
• Engagement: 8-12 weeks freelance (extension possible)
• Paid in fiat