Backend Software Engineer (Senior/Staff)

Dualentry; Warszawa; Remote; PLN 365,000 - 604,000; Full time

Job summary

A fast-growing AI startup is seeking a Senior/Staff Backend Engineer to design and build core systems. This remote role involves owning backend execution, building APIs, and collaborating with cross-functional teams. Candidates should have 8+ years in backend engineering, strong skills in Python, PostgreSQL, and experience in high-growth settings. Competitive salary and equity options available.

Benefits

Base Salary: $100K–$165K USD

Equity: ~$50K USD

15 PTO days + 12 public holidays

Visa sponsorship option for relocation

High autonomy and long-term upside

Qualifications

• 8+ years of experience in backend engineering.
• Proven track record in high-growth environments.
• Strong skills in PostgreSQL, SQL, ORMs, migrations.

Responsibilities

• Own end-to-end execution for backend systems.
• Build APIs and services handling complex logic.
• Collaborate with product and frontend engineering.

Skills

Backend engineering

Python

CI/CD

PostgreSQL

API design

English (C1+)

Tools

AWS

FastAPI

Flask

Django

Job description

Why This Role Matters Now

Since launching 18 months ago, we’ve raised $100M with backing from Lightspeed, Khosla, and Google Ventures. We got there by moving incredibly fast and hiring the best and brightest talent. To accelerate that momentum, we’re growing our team. Come and join us at one of NYC’s fastest-growing startups and have an impact on our product from day one.

As our Senior/Staff Backend Engineer, you’ll design and build core systems end-to-end, architect real-time business-critical workflows, and ship production-ready features daily. This is an intense, hands‑on role with full ownership.

You’ll be joining at an early and defining moment. Your work will directly shape our product, customers, and trajectory.

📍Location: Remote - this role is available across all EU/LATAM countries with overlap for the US ET timezone (NYC HQ)

About DualEntry

Founded in 2024, DualEntry is one of NYC’s fastest-growing AI startups.

DualEntry is changing the future of finance. Our AI-native ERP lets teams achieve more in less time. $5M-ARR businesses and NYSE-listed companies trust DualEntry to automate away busywork and fuel their growth with powerful reporting and insights. We’re making the one-person finance team a reality and putting the pain of legacy ERPs from the 1990s in the past.

We operate with urgency and ownership. We move fast.

Where you'll create impact

• You’ll own end-to-end execution for backend systems and infrastructure
• You’ll build APIs, services, and real-time systems handling complex accounting logic
• You’ll collaborate with founders, product, and frontend engineering to turn complex workflows into secure, performant systems
• You’ll design, implement, and ship production-ready features at high speed
• You’ll manage data migrations, scaling challenges, external integrations, and end-to-end reliability
• You’ll drive measurable outcomes that accelerate DualEntry’s product velocity and stability

What sets you up for success

• 8+ years of experience in backend engineering
• Proven track record in high-growth, high-ownership environments
• Deep expertise in Python and modern frameworks (FastAPI, Flask, or Django)
• Strong skills in PostgreSQL, SQL, ORMs, migrations, and schema design
• Experience with AWS or comparable cloud infrastructure
• Strong API design and testing experience
• Understanding of CI/CD, deployment, and production readiness
• Ability to manage complex systems with evolving requirements
• Fluent English (C1+) with clear communication

Why you’ll thrive here

• 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 culture
• High-trust environment with high expectations
• Ambitious mission

Benefits

• Base Salary: $100K–$165K USD
• Equity: ~$50K USD
• Contract type: B2B
• Remote-first team - the fastest team you will have ever worked with
• Time Off: 15 PTO days + 12 public holidays
• Visa sponsorship option for relocation to NYC within 2+ years
• Early-stage role with high autonomy and real long-term upside

If you’re excited by fast-paced building, ownership, and the chance to define the future of finance technology, we’d love to hear from you!

At DualEntry, we believe great products come from diverse teams. We’re an equal opportunity employer, and we’re committed to a culture where everyone feels included, supported, and able to do their best work.