Senior/Staff Backend Engineer (London, Hybrid)

DualEntry is building the OS for finance.

Every business needs a financial system of record, yet the world's largest fintech market ($220B+) still runs on software from the 1990s. DualEntry's AI-native ERP automates accounting from data entry to close, so finance teams move faster, spend less and incur less risk.

In just 2 years we've raised $100M+ from Lightspeed, Khosla Ventures, Contrary and Google Ventures and earned the trust of customers from $5M ARR to publicly traded companies.

We hire outliers - people who have achieved difficult things, in their careers or beyond. You'll find leaders, colleagues who've competed at the highest levels of sport, performed on Broadway, trained with UFC champions and founded the country’s largest Python community.

• Build!

• Design backend systems and APIs (Python preferred) that run real-time, business-critical accounting logic

• Ship features end to end - architecture, CI/CD, testing, monitoring, and beyond

• Integrate third-party tools and external systems, proactively managing edge cases and risk

• Hardcore work ethic and high agency

• 5+ years in backend engineering (language agnostic)

• Deep experience with complex business logic products

• Strong database skills: PostgreSQL, SQL, ORMs, migrations, schema design

• Experience deploying on AWS (or similar), with solid CI/CD and production-readiness fundamentals

• Bonus: Python and a modern web framework (FastAPI, Flask, or Django)

• Significant equity ownership in one of the top AI companies in the world

• You’re joining early and will grow with DualEntry

• Your feedback shapes the product directly

• High-speed, high-trust environment with high expectations

   

• Ignacio shaped the baseline of our integration framework from scratch in a single weekend, then spent most weekends - while coordinating the team - shipping what was never on the roadmap: webhooks, a search engine for millions of transactions, and Puma itself. Pure initiative, compounding.

• Marcin took a non-existent tax structure and built it end to end, setting the north star for how the team keeps improving it on top of it; modular and robust, always setting the bar for the rest.

• Puhiza grew her team from one to full capacity, while owning our integration framework end to end; scaling it to support migrations, integrations, and bank connections. The queen of I/O on our platform.

• Danylo took ownership of our bank connection engine end to end and rebuilt it from scratch.

   

• Pragmatic: you like to move forward and make decisions based in reality (not theory). We don't debate if Cassandra has the most theoretical scalability - we use Postgres until it breaks

• Hard working: 'You can work long, hard, or smart, but [here] you can't choose two out of three' - Jeff Bezos.

• Curious: you love to learn, are highly curious about new frameworks and solutions to engineering problems

• Fast-moving: you deploy daily, iterate quickly, and never wait for permission

   

• Equity: £40,000 - £70,000

• Base salary: £130,000 - £220,000

• Private medical insurance through Freedom Elite

• Mental health support (Talkspace)

• Fertility support (Carrot)

• Group life insurance (Allianz)

• Workplace pension through Penfold (with salary sacrifice option)

• Flexible PTO (28 days, including public holidays)

• Home internet, co-working space & office setup support

• Unlimited AI token usage

• AI skills development & enablement

• Learning & development budget for courses, certifications & language learning

• Visa sponsorship and relocation support for a move to NYC (after 2 years' tenure)

• In-person team meetups (our last ones: Lisbon, Vienna, Warsaw, Cyprus and more!)

“Join us to fix the boring, think the hard, and build the impossible, so we become the most robust engineering platform for accounting the world has ever seen.”

Ignacio Brasca, Head of Engineering at DualEntry