Senior Backend Engineer - Scale FinTech (AI-Driven)

0to9 AB (publ); Stockholms kommun; On-site; SEK 669,600 - 892,800; Full time

Job summary

0to9 AB (publ) is seeking a Senior Engineer to join their team in Stockholms kommun, Sweden. In this role, you will shape the architecture and own critical technical decisions while building scalable infrastructure. Your experience in SaaS and startup environments will help you thrive in this fast-paced, early-stage company.

If you're looking to contribute to a product being designed from scratch with significant growth potential across Europe, we want to hear from you.

Qualifications

• Senior backend developer with experience from SaaS or high-growth companies.
• Comfortable in startup environments with fast pace and broad ownership.
• Prioritizes product and simplicity over flashy technology.

Responsibilities

• Shape architecture and own technical decisions.
• Build infrastructure that scales.
• Utilize AI tools in workflow.

Skills

Python

SQL/Postgres

HTMX

AWS core services

AI tools (Cursor, Claude Code, Copilot)

Job description

0to9 AB (publ) is seeking a Senior Engineer to join their team in Stockholms kommun, Sweden. In this role, you will shape the architecture and own critical technical decisions while building scalable infrastructure. Your experience in SaaS and startup environments will help you thrive in this fast-paced, early-stage company.

If you're looking to contribute to a product being designed from scratch with significant growth potential across Europe, we want to hear from you.