Senior Engineer Till Aoto

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

About AOTO

AOTO is a Swedish fintech company building a digital operating system for car dealers, combining inventory financing, automated bookkeeping and digital services like leasing, warranties and insurance in one platform. The goal is simple: help car dealers make faster, smarter decisions and maximise their buy and sell potential.

We're in an exciting early stage as part of the 0TO9 ecosystem, building the product from scratch with clear ambitions to expand across Europe. This role is central to getting us there.

The Role

We're looking for a Senior Engineer who thinks beyond code. You'll shape architecture, own technical decisions and build infrastructure that scales. You're curious, pragmatic and you know that the right technology isn't always the one that looks best on a CV.

What we work with:

• Python and SQL/Postgres
• HTMX
• AWS core services

Who you are

• Senior backend developer with experience from SaaS or high‑growth companies
• You're comfortable in startup environments, fast pace, broad ownership and constant change don't scare you
• You think about the product, not just code, and take responsibility beyond your own tasks
• You prefer simplicity and technology that works over flashy technology that impresses
• You actively use AI tools in your daily workflow (Cursor, Claude Code, Copilot or similar), this isn't a nice to have, it's a must

Why AOTO?

• Join early and help shape a product that's being built from the ground up
• Your decisions actually matter, no layers, no bureaucracy
• Work closely with CEO Marc Blomberg and CTO Henrik Lagercratz
• Grow with the company as we expand into new European markets

Find out more at aoto.se, we'd love to hear from you!