Senior Python Backend Engineer - Finance

Why Fulfil
Fulfil is a technical founder-led, bootstrapped company in our 11th year of operations. We're a small team of exceptional engineers powering millions of orders for brands like HexClad, Ridge Wallet, and Caraway. No red tape. No product managers. No layers of approval. You'll own systems where accuracy is non-negotiable and ship to production in your first two weeks.

You'll work directly with our Product Support team, who talk to merchants daily. They bring you real problems, you propose solutions, you ship. No PRDs. No one translating customer pain through three layers of abstraction.

At a large company, senior engineers attend meetings. Here, you'll architect financial systems, ship them yourself, and see CFOs trust their books because of your code.

The Team
Finance owns accounting, reconciliation, revenue recognition, and financial integrations. Mission: books close on time with transactions posted automatically. We serve controllers and CFOs processing millions in monthly revenue.

A Typical Week

• Monday: Lead design review for multi-currency consolidation. A merchant with 5 countries needs to close books across entities. Design the data model and posting rules.
• Tuesday: Build the consolidation engine. Test against production data from a merchant doing $10M/month across USD, EUR, GBP.
• Wednesday: Call with a merchant's CFO. Walk through revenue recognition requirements for their new subscription line. Translate to technical spec.
• Thursday: Code review for two SDE-IIs on bank reconciliation. Guide them on partial matches and split transactions.
• Friday: Ship multi-currency consolidation. Watch a merchant run their first consolidated close in minutes instead of days.

What You'll Own

• Financial posting architecture: rules engine, multi-currency, consolidation
• Reconciliation reliability and matching accuracy
• Bank and gateway integration framework
• Technical direction (with Product Lead)
• Mentoring engineers

What We're Looking For

• 4-6 years building backend systems
• Experience with financial systems, fintech, or accounting software preferred
• Expert Python, complex business logic
• Deep PostgreSQL: transactions, isolation levels, data integrity
• Meticulous testing discipline
• Clear communication with finance professionals

Tech Stack
Python PostgreSQL Redis Celery SQLAlchemy Kubernetes pytest Claude Code

Hiring Process

• Initial interview — Experience with financial systems
• Live coding — Real-time problem solving
• Interview loop — Architecture, domain expertise, bar raiser
• Bootcamp — Even senior engineers start in Product Support to learn how merchants use Fulfil