Senior Backend Developer

Qasa; Stockholms kommun; On-site; SEK 900,000 - 1,100,000; Full time

Benefits offered by this job

Central Stockholm office

Generous wellness grant

Equipment provided

Open Friday afterwork

Collaborative culture

Job summary

Qasa, the leading rental platform in Sweden, is seeking a senior Ruby backend developer to shape the platform used by thousands across the Nordics. You design and build our scalable backend system in Ruby on Rails, working closely with product, design and other engineers to deliver features end-to-end and maintain APIs and internal services.

You will contribute to architectural decisions, take ownership from idea to production, and mentor junior colleagues.

Qualifications

• 10+ years of backend experience with Ruby/Rails or similar OO languages.
• Strong grasp of system design and scalable architectures.
• Commitment to maintainable and readable code over clever abstractions.
• Experience building libraries for internal use when needed.

Responsibilities

• Design and build a scalable backend system in Ruby on Rails.
• Collaborate with product, design and engineers to deliver features end-to-end.
• Improve and maintain APIs and internal services.
• Contribute to architectural decisions and technical direction.
• Take ownership from idea to production and mentor juniors.

Skills

Ruby

Ruby on Rails

Backend design

Code quality

Tools

Postgres

Redis

ElasticSearch

GoodJob

Minitest

Inertia+React

GitHub

AWS

Honeybadger

Job description

• Postgres, Redis, ElasticSearch, GoodJob

Let's shape the future of renting together.

Qasa is a fast-growing scale-up transforming the rental housing market across the Nordics. Since launching in 2014, we’ve been focused on making renting easier, safer, and more accessible for both landlords and tenants. What started as a small startup is now the leading rental platform in Sweden— and we’re just getting started. We’re expanding across the Nordics with a highly skilled, driven team passionate about building a product that makes a real difference in people’s lives. If you’re excited about having a meaningful impact on a product that helps people find and rent homes, one of life’s most essential needs, then you might be the person we’re looking for.

Who we are

We’re now looking for another senior Ruby backend developer to join our team and help shape the platform behind the rental experience for thousands of people across the Nordics.

What will you do

• Design and build our scalable backend system in Ruby on Rails
• Work closely with product, design, and other engineers to deliver features end-to-end
• Improve and maintain our API and internal services
• Contribute to architectural decisions and technical direction
• Take ownership of your work, from idea to production
• Mentor and inspire junior colleagues

What you have

• 10+ years of backend experience, preferably with Ruby and Ruby on Rails (or similar object-oriented languages like Python)
• A solid grasp of system design and architectural principles
• The ability to structure clean, modular, and scalable codebases
• A strong preference for writing maintainable, understandable code over clever abstractions
• Confidence in building libraries for internal use, when off-the-shelf libs fall short

Who you are

You’re humble, collaborative, and thoughtful — someone who sees software development as a team sport. You don’t guard “your” code and are always ready to pair up, share ideas, and iterate together. You take pride in delivering quality work, but never at the expense of others. You thrive in a fast-moving environment, learn quickly, and enjoy challenging yourself. You’re driven to get things done — not because of pressure or competition, but because you care about your work’s impact. You value clear communication, kind feedback, and supporting your teammates. The right mindset and a strong cultural fit are more important than checking every box on a tech list. If that sounds like you, you’ll feel right at home here. You’re self-driven and comfortable taking initiative, whether that means improving an existing system, suggesting a better approach, or picking up something that needs doing. You care about progress and quality, and you enjoy helping move both the product and the team forward.

Why Qasa?

• A supportive and ambitious team that cares about what we’re building
• A real product solving real problems — used by people every day
• Flexible work: join us in our bright, modern office at Medborgarplatsen in central Stockholm
• Competitive salary and benefits
• A chance to make a meaningful impact in a growing company

Tech stack

• Ruby 4.0
• Rails 8.1
• Minitest, Inertia+React
• Postgres, Redis, ElasticSearch, GoodJob
• GitHub, AWS, Honeybadger

Hiring process

• Initial screening call – a brief conversation about your background, experience, and what you’re looking for (~30 minutes)
• Technical interview with the Hiring Manager – a deeper dive into your technical experience, including hands-on pairing (~1.5 hours, on-site)
• Culture interview with our CTO and our CPO – a discussion of values, collaboration, and how we work together (~1 hour, on-site)
• Offer and reference checks

Perks And Benefits

• Central location – Right in the middle of Södermalm in Stockholm. This is a place for you to find working peace without ever being more than one elevator ride away from the pulse of the city.
• Generous wellness grant – We provide you with a generous wellness grant (Friskvårdsbidrag). If you feel good, the company feels good. Simple as that.
• All equipment you need – We supply you with quality equipment when you work with us. Let us know what you need to thrive, and we will get it for you.
• Open door afterwork – On Fridays, we get together for a beer or two. Feel free to invite friends!
• Collaborative Community – We work and play together. We help each other to reach our goals. Together we are stronger.