Senior Software Engineer - Pay & Safety

Cacheflow; San Francisco (CA); On-site; USD 130,000 - 160,000; Full time

Benefits offered by this job

Equity in a fast-growing company

401(k) match

Paid parental leave

Medical, dental, and vision benefits

$2,000 learning stipend

Job summary

Handshake is seeking a Senior Software Engineer in San Francisco to own payout and money movement systems. The ideal candidate has over 5 years of experience in high-stakes software engineering, with solid skills in payment systems and backend development using Ruby on Rails and PostgreSQL. Responsibilities include building Trust & Safety tools and leading engineering practices. Attractive perks offered include equity, comprehensive health benefits, and professional development stipends.

Qualifications

• 5+ years of professional software engineering experience in high-stakes domains.
• Ability to design highly reliable, zero-downtime systems.
• Deep proficiency in relational databases and schema evolution.

Responsibilities

• Design and build payout systems supported by Payment Service Providers.
• Build the Trust & Safety stack for fraud screening and audits.
• Lead schema design and migrations across Postgres.

Skills

Software engineering experience

System design fundamentals

Proficiency with PostgreSQL

Backend skills in Ruby on Rails

Experience with React

Communication and stakeholder management

Mentoring engineers

Tools

Ruby on Rails

TypeScript/Node

PostgreSQL

Temporal

Stripe

Job description

About the Role

As a Senior Software Engineer on the Pay squad, you'll own the systems that move money to Handshake AI's global fellow workforce. That includes earnings calculation, payout generation, Stripe-backed disbursement, and the operator tooling that runs every pay cycle. You'll also be helping us build out a much more sophisticated Trust & Safety surface area: KYC and identity verification, sanctions and fraud screening, and time‑tracking audit systems that catch suspicious activity throughout Handshake AI.

This is a role for engineers who treat reliability, auditability, and resilience as first‑class design constraints. Pay can't go down. Ban decisions can't be silent. Webhooks can't be lost. You'll set the bar for how these systems are designed, deployed, and verified. Our work spans across microservices and integrations with payment and trust and safety providers.

What You’ll Do

• Design and build payout and money‑movement systems on top of Payment Service Providers, including onboarding, KYC, country and payout‑method support, webhook reconciliation, retries, and rate‑limit handling, with zero‑downtime rollout and full auditability for every state change.
• Build out a robust and flexible payment and incentives platform that powers how fellows are compensated, rewarded, and retained across every project we run.
• Build the Trust & Safety stack: KYC and re‑verification flows, sanctions and fraud screening, ban and suspicious‑account state transitions, and time‑tracking audits over activity, time confirmations, and pay rates.
• Own operator tooling, including the Pay admin dashboard, ledger, and operations that let our ops team run pay weeks safely.
• Lead end‑to‑end on schema design, migrations, and backfills across Postgres and design rollouts that are safe to deploy.
• Set the bar for engineering practices on the squad through system design reviews, incident response, runbooks, and observability, and mentor other engineers through code review and architectural guidance.

What We’re Looking For

• 5+ years of professional software engineering experience, with meaningful time spent owning production systems where correctness and uptime matter (payments, fintech, identity, fraud, infrastructure, or similar high‑stakes domains).
• Strong system design fundamentals for highly reliable, zero‑downtime, auditable, and resilient systems: expand‑contract migrations, idempotency, retries and backoff, dual‑writes and backfills, append‑only audit logs, and reconciliation jobs.
• Deep proficiency with relational databases (PostgreSQL), data modeling, and schema evolution under load. You can defend why a given state is or isn’t reachable.
• Strong backend skills in Ruby on Rails and/or TypeScript/Node, and willingness to work fluently across both.
• Comfort in React for operator and fellow‑facing UI.
• Experience designing and operating asynchronous workflows (Temporal, Sidekiq, or similar) and integrating with third‑party APIs that fail in interesting ways (Stripe, Deel, Hubstaff, or equivalents).
• Track record of leading technical projects end‑to‑end in ambiguous environments, with a bias toward shipping behind feature flags and verifying in production.
• Excellent communication and stakeholder management. You can partner with Ops, Finance, Legal, and Compliance and translate their requirements into system invariants.
• Track record of mentoring engineers and raising the engineering bar on a team.

Nice to Have

• Prior experience building production payments, payout, or money‑movement systems
• Background in Trust & Safety, fraud, KYC/AML, sanctions screening, or identity verification at scale.
• Experience with event sourcing, change‑data‑capture, or audit‑log architectures where every state change is reconstructable.
• Experience operating comparable workflow orchestrators for long‑running, idempotent business processes.
• Experience with regulated or compliance‑driven workstreams (1099‑NEC issuance, OFAC, GDPR/data deletion, SOC 2 controls).

Perks

Ownership: Equity in a fast‑growing company

Financial Wellness: 401(k) match, competitive compensation, financial coaching

Family Support: Paid parental leave, fertility benefits, parental coaching

Wellbeing: Medical, dental, and vision, mental health support, $500 wellness stipend

Growth: $2,000 learning stipend, ongoing development

Office: Commuting support, free lunch, and gym in our SF office

Time Off: Flexible PTO, 15 holidays + 2 flex days

Connection: Team outings & referral bonuses