A Swedish fintech that lets anyone invest in individual stocks, guided by algorithms instead of guesswork. We were their engineering team before they had one.
Founded in 2014 by Nanna Stranne, Mai Thai and Carl Lindberg, Sigmastocks was a fintech startup with a sharp idea and no developers: use algorithms and big data so anyone can invest in individual stocks without being an expert. Long-term, transparent, fair. What they did not have yet was a team to build it.
That is where we came in. We ran a workshop to map the users, the constraints and the real challenges, then built the first prototype from the roadmap that came out of it. We are one of Scandinavia’s most experienced Ruby on Rails teams, so Rails was the natural choice: a tailored product we could sharpen in tight iterations.
Together with Sigmastocks we built the system that handles customer data and works out each user's monthly savings, and integrated it with Nordnet so buying stocks took a few clicks, not an afternoon. For a young company without in-house developers, we were the team that turned the idea into a product.
Users could build their own portfolio from Sigmastocks’ mathematical models. The new platform took the customer base from 300 to 2,500 paying users in under two years, growing 20% a month.
The founders went on to be named Sweden’s top finance talents by Veckans Affärer in 2018, and in 2025 Avanza acquired Sigmastocks to build out its digital discretionary management. We built the first version of the platform, on Ruby on Rails, JavaScript, HTML5 and CSS3.
“Varvet helped us rebuild our web and has contributed with web development since. We are very satisfied with the collaboration and especially pleased with the work provided.”
Mai and Nanna took Sigmastocks from a sharp idea to thousands of customers, and eventually an acquisition by Avanza. We were proud to build the first version with them, and grateful to have been part of the start.
Want to know more about this project or how we work, contact Jon.
We were Sigmastocks' engineering team before they had one. Tell us what you're building.
