Note: The job is a remote job and is open to candidates in USA. Offchain is a pioneer in blockchain scalability and security, transforming how the world interacts with decentralized applications. They are seeking a Senior Software Engineer for their Developer Platform team to build and maintain key-management services that ensure secure wallet creation and signing processes.
Responsibilities
- The Developer Platform team builds KMS, the key-management and signing service behind ZeroDev's embedded wallets (smart-account / account-abstraction wallets that app developers drop into their products). It is non-custodial: end users control their keys, and the service orchestrates secure creation, authentication, and signing on top of a third-party signing provider. This is security-critical infrastructure, externally audited, with a high review bar. You will own backend services and the cryptographic recovery and trust-model machinery around them on a small, high-ownership team, and help grow the platform from interactive consumer wallets toward programmatic and automated signing and programmable transaction policy
- Go backend services that broker wallet creation, authentication, and signing at scale
- Key recovery and the committee trust model: distributed key generation and secret sharing that keep the service non-custodial, with recovery authority split across independent committees so no single party ever holds a user's key
- Trusted Execution Environments: reconstructing and operating on key material under hardware isolation and remote attestation
- Authentication and signing-provider integration: the user-facing auth methods that gate signing (passkeys / WebAuthn, OAuth, OTP, sessions, 2FA), and integrating with a third-party signing provider (authorization and policy flows, scoped credentials, quorum / consensus approvals)
- Security review and hardening: writing design docs and decision records, working directly with external security auditors, and turning a high review bar into shipped code
- Production operations on Kubernetes: observability and alerting, secrets and certificate management, on-call, and the compliance controls the domain requires (sanctions screening, PII-safe handling)
Skills
- A strong backend engineer who has shipped and operated production services in Go (or an adjacent systems language and is eager to go deep in Go)
- Security-first by default: you reason about threat models, blast radius, and key custody as a habit, and you write code that holds up to security-critical review
- Comfortable with applied-cryptography fundamentals (public-key crypto, signatures, key management). You do not need to be a cryptographer, but you can reason about it and learn fast
- Solid on distributed systems and API design: idempotency, failure modes, and clean service boundaries
- Operationally mature: Kubernetes, observability, and incident response are not foreign to you
- Clear written communicator (design docs, decision records) who thrives in a collaborative, review-heavy culture
- TEE experience (AWS Nitro Enclaves, Intel SGX / TDX, or similar): attestation, enclave key handling, reproducible enclave builds
- Threshold cryptography / MPC in practice: DKG, FROST or other threshold signatures, verifiable secret sharing, resharing
- Account abstraction: ERC-4337, EIP-7702, smart-account or embedded / non-custodial wallet experience
- Built on or integrated a custody / signing provider (Turnkey, Fireblocks, or similar), or built one
- HSM / YubiKey / PIV / secure-element integration
- Been on the receiving end of a third-party security audit and driven the remediation
- WebAuthn / passkeys, OAuth / OIDC, and the Go crypto ecosystem
Benefits
- Remote-first global workforce + NY office
- Annual company offsite + team onsites
- Professional reimbursement program (facilitates industry conference attendance, certifications, and more)
- Medical, dental & vision coverage (US + some other countries)
- 401k retirement plan + company match (US only)
- Wellness stipend
- Home office set up / ergonomic equipment program
Company Overview
Company H1B Sponsorship