Staff Engineer - FinTech Platform & AI Payments

Polymer; New York (NY); Remote; USD 220,000 - 250,000; Full time

Job summary

Eli is hiring a Staff Engineer to own systems where money moves, AI-driven decisions, and platform reliability. You will ship code weekly, set technical direction, and work closely with cofounders to mature a production-grade payments platform.

This role is based in New York with the option for fully remote work within the US, and is open to US residents only. You'll own critical components—ledger, decisioning, and tooling—while mentoring teammates and shaping how engineering scales as the

Qualifications

• 8+ years building production software and responsible for a system in production.
• Staff-level scope or equivalent impact: led the design of a system others build on and stayed accountable for it in production.
• Deep TypeScript on the backend (Bun, Node, Next.js, tRPC, Prisma or similar) and solid relational database skills in MySQL or Postgres: schema design, query plans, migrations.
• A track record of taking on work outside your assigned lane and finishing it.

Responsibilities

• Set technical direction for money movement, decisioning, and platform evolution; write designs for others to implement.
• Own end-to-end product: determine processors, contractors, and admins needs and ensure production readiness.
• Define AI decisions that move money: verification, eligibility checks, fraud detection; decide model vs rule vs human and measure outcomes.
• Maintain ledger accuracy and reconciliation with bank records; ensure audit readiness and cent-level precision.
• Improve internal tool stack by consolidating systems into in-house tools for operations and configurations.
• Oversee platform and production: CI speed, test-health, backups, migrations, alerts, and root-cause fixes.

Skills

Production software experience

Staff-level scope

Deep TypeScript backend

Relational databases (MySQL/Postgres)

Tools

Temporal

dbt

Snowflake

Docker

Pulumi

Vercel

Datadog

Sentry

Claude Code

Job description

Eli is hiring a Staff Engineer to own systems where money moves, AI-driven decisions, and platform reliability. You will ship code weekly, set technical direction, and work closely with cofounders to mature a production-grade payments platform.

This role is based in New York with the option for fully remote work within the US, and is open to US residents only. You'll own critical components—ledger, decisioning, and tooling—while mentoring teammates and shaping how engineering scales as the