Software Engineer - Wallets

Stack

Responsibilities

• ▹Own the architecture of Rain's wallet infrastructure: secure, scalable systems for custody, key management, transaction signing, authorization and recovery
• ▹Design flexible signing infrastructure supporting MPC, HSMs, secure enclaves, TEEs and emerging cryptographic approaches without fragmented systems
• ▹Build and evolve wallet systems across multiple account models: EOAs, smart contract wallets, account abstraction, ERC-4337, embedded wallets and multichain infrastructure
• ▹Define the boundaries between cryptography and wallet orchestration: how keys, signing authority, transaction policies, permissions and authorization interact
• ▹Architect security-critical key management systems: key generation, distributed key generation, storage, rotation, backup, recovery and hardware-backed isolation
• ▹Build highly available signing and transaction infrastructure that securely controls high-value customer assets with developer-friendly APIs
• ▹Set the technical direction for wallet security: threat modeling, policy engines, secrets management, account recovery, authentication and programmable authorization
• ▹Make foundational build-vs-buy decisions across cryptography, custody, wallet and security infrastructure

Requirements

• ▹Deep expertise in one or more areas of wallet, custody, cryptography or security infrastructure, with strong distributed systems and architecture fundamentals
• ▹Experience designing or building production wallet, custody, signing or key management systems, particularly for high-value assets
• ▹Strong knowledge of applied cryptography: MPC, threshold cryptography, threshold signatures, distributed key generation, ECDSA, EdDSA, secure multiparty computation
• ▹Experience with HSMs, secure enclaves, TEEs, confidential computing or hardware-backed key isolation
• ▹Strong understanding of modern wallet and blockchain account architecture: EOAs, smart contract wallets, account abstraction, ERC-4337, transaction orchestration, multichain systems
• ▹Experience designing authentication, authorization, policy, permissions, recovery or secrets-management systems where security and correctness are critical
• ▹Track record of high-leverage architectural decisions in complex distributed systems, weighing tradeoffs across security, reliability, developer experience and extensibility
• ▹Ability to form strong technical opinions, communicate tradeoffs clearly and own architecture from first principles through production

Soft skills

What we offer

• ▹Unlimited time off (minimum of 10 days required)
• ▹Flexible working: from home, an office or both
• ▹Home workspace stipend for new team members
• ▹For US employees, 95% of health, dental and vision costs covered and 90% for dependents, plus company-subsidized life insurance
• ▹401(k) with 4% company match
• ▹Equity option plan for everyone
• ▹Monthly health and wellness stipend
• ▹In-office meals covered with a DoorDash credit
• ▹Team and company offsites, domestic and international

About the company

Rain is the global stablecoin payments platform for enterprises, neobanks, platforms, developers and AI agents. As a Visa and Mastercard Principal Member it issues cards that work at more than 175 million merchant locations in over 220 countries and territories, and it closed a $250M Series C in January 2026.