Most founders raise money to survive their first year. Mathis Büchi and Lino Teuteberg had already done something rarer: they had built a profitable company without outside capital. That company was Smallpdf, a humble tool for merging and compressing PDF files, and it taught two Swiss friends how little a good product needs to be flashy if it removes a daily irritation.
Then they moved to Germany and noticed another irritation, a far bigger one. Millions of people were owed money by the tax authorities and never claimed it, simply because the paperwork felt like a threat. Büchi later talked about seeing people lose money by avoiding their returns. The company's own account is that the two had years of friendship and shared projects behind them before deciding to take on a topic everyone dreads.
Still, the app kept growing in a seasonal business that peaks every spring.
They founded Taxfix in Berlin in 2016. The early product label, as one German outlet called it in 2016, was a friendly tax bot. The bet was simple: do not ask people for tax vocabulary, ask them plain questions and do the translating behind the scenes. For a country where tax software had long been built for accountants, that was a different tone.
What made investors lean in was the size of the unfiled pile. Index Ventures led a USD 65M Series C in 2020 and Neil Rimer joined the board. In September 2021 Büchi stepped back from the chief executive role to become chairman, and Martin Ott took over while Teuteberg kept shaping the product.
The next year looked like the dream. In April 2022 Taxfix raised USD 220M at a valuation above USD 1bn, joining Berlin's unicorn list. But the timing was brutal. As funding dried up, the company cut 120 jobs, about one fifth of staff, in May 2023, and headcount fell from over 500 to just over 300 across several rounds.
Still, the app kept growing in a seasonal business that peaks every spring. A third-party estimate puts 2024 revenue near USD 56.6M, though that figure is not company-confirmed.
The lesson is that the unglamorous edge counts. The founders who made PDFs simple earned the right to make taxes simple, and they did it with a reputation for profitable thinking. When money flooded in, the discipline they had learned from bootstrapping was the thing the company had to relearn.