Senior Backend Engineer, ZeroDev Wallet

At Offchain Labs, you'll join the Developer Platform team building KMS, the key-management and signing service behind ZeroDev's embedded, non-custodial wallets. You'll own production Go services and the cryptographic recovery and trust-model systems that power smart-account wallets developers integrate directly into their applications. This is security-critical infrastructure with a high review bar and external security audits, where end users retain control of their keys while KMS security orchestrates wallet creation, authentication and signing.

What you'll do

• Build and operate Go services that power wallet creation, authentication, and signing at scale
• Design and implement key recovery and the committee trust model, using distributed key generation and secret sharing to keep the service non-custodial, with recovery authority split across independent committees so no single party holds a user's key
• Reconstruct and operate on key material under hardware isolation and remote attestation using Trusted Execution Environments
• Implement user-facing authentication methods (passkeys / WebAuthn, OAuth, OTP, sessions, 2FA) and integrate with a third-party signing provider, including authorization flows, scoped credentials, and quorum / consensus approvals
• Write design docs and decision records, work directly with external security auditors, and turn a high review bar into shipped code
• Operate production services on Kubernetes, including observability and alerting, secrets and certificate management, on-call, and compliance controls such as sanctions screening and PII-safe handling

What you bring

• Strong backend engineering experience shipping and operating production services in Go (or an adjacent systems language and willing to go deep in Go)
• Security-first mindset: you naturally think about threat models, blast radius and key custody, and write code that holds up to security-critical review
• Understanding of applied cryptography fundamentals such as public-key cryptography, signatures and key management, and ability to reason about how they apply to production systems (you do not need to be a cryptographer)
• Solid grounding in distributed systems and API design, comfortable reasoning about idempotency, failure modes and clean service boundaries
• Operational experience with production infrastructure, Kubernetes, observability and incident response
• Clear written communication skills, able to explain technical decisions through design docs and decision records, and work effectively in a collaborative, review-heavy environment

Nice to have

• Experience with Trusted Execution Environments (TEE) such as AWS Nitro Enclaves, Intel SGX / TDX or similar
• Threshold cryptography / MPC, including DKG, FROST or other threshold signatures, verifiable secret sharing or resharing
• Account abstraction, including ERC-4337, EIP-7702, smart accounts or embedded / non-custodial wallets
• Custody or signing infrastructure such as Turnkey or Fireblocks, either as an integrator or builder
• HSMs, YubiKey / PIV or secure-element integrations
• Third-party security audits and driving remediation through to completion
• Authentication technologies such as WebAuthn / passkeys and OAuth / OIDC, or experience with the Go crypto ecosystem

What we offer

• Remote-first global workforce with a New York office
• Professional reimbursement program (industry conference attendance, certifications, and more)
• Medical, dental and vision coverage (US and some other countries)
• 401k retirement plan with company match (US only)
• Wellness stipend
• Home office setup and ergonomic equipment program

About Offchain Labs

Offchain Labs built the Arbitrum stack that powers Arbitrum One, the most widely adopted Ethereum scaling solution today. The Arbitrum ecosystem includes hundreds of projects and dApps, with over 100 teams using Offchain technology to build their own Arbitrum chains. Major players such as Robinhood, BlackRock, Ethena Labs, Securitize, Aave, and Apechain use the Arbitrum stack. Offchain is backed by $124 million in funding and has demonstrated consistent execution with billions in secured value, thousands of supported projects, and infrastructure processing millions of transactions.