On September 21, 16 startups took the stage at Constructor University in Bremen for the fourth Constructor Start Demo Day. They were selected from more than 2,100 applications across 70+ countries, with 35 companies entering the latest cohort before the field narrowed to the final 16.
By the end of the day, PolaSight, The Lithium Company and Hi Holo had each received a $100,000 investment from Constructor Capital. The winners reflected the technical range of the cohort, spanning medical imaging, battery restoration and AI.
Demo Day closed an eight-week program combining mentoring, business development and investor feedback. Constructor Start is designed to help early-stage teams move from an idea or early product toward an investable company. For Constructor Capital, it also brings technical founders into the fund's orbit earlier than a conventional fundraising process.
Built for deep tech
Constructor Capital has been involved in the program from the beginning as lead sponsor and co-organizer. Dr. Matthias Winter, Managing Director and General Partner, said the decision to build a dedicated accelerator rather than rely on an external program was deliberate.
“We didn't want to partner with somebody because we wanted to have something specific. There are very few programs focused on deep tech, so we made Constructor Start specific to deep tech and want to attract great entrepreneurs and business builders into the program.”
Dr. Matthias Winter, Managing Director and General Partner at Constructor Capital
That specialization matters because deep-tech companies rarely follow the same commercialization path. A software startup can test distribution while its product changes quickly. A medtech company may need clinical evidence and regulatory planning. A photonics or quantum startup can move through years of technical milestones before a commercial system is ready.
Constructor Start is built around that gap between technical promise and commercial readiness. Constructor Capital team members mentor participating companies, contribute to fundraising sessions, join the jury and help evaluate startups for further mentorship and investment. The wider Constructor ecosystem adds access to university researchers, technical experts and industry contacts.
Marie Lepske, General Partner at Constructor Capital, said the earliest investment decisions are less about expecting a finished business and more about whether the core building blocks are credible.
“In early stages, we look first of all at the team, the potential of the technology and whether there is a clear intellectual property position,” Marie said. “We also look at the potential of the go-to-market strategy and whether there is a clear path for the team to execute it before the next funding round.”
Marie Lepske, General Partner at Constructor Capital
The same technical focus was visible at Demo Day. Marie Lepske presented “Quantum Momentum 2.0,” followed by a panel on quantum computing, bringing academic, technology and investment perspectives into the same program as the startup pitches.
A longer view of potential investments
For Constructor Capital, Constructor Start also functions as a sourcing channel. Dr. Valentino Jadriško, Senior Associate at the fund, said the program creates a chance to assess companies through repeated interaction rather than a small number of investment meetings.
“One part of making our job successful is sourcing and finding good companies, and Constructor Start helps with that,” Valentino said. “We get the chance to work with founders for a longer period, see the progress they make and then decide whether we want to invest.”
That additional context actually matters in deep tech. Diligence is not limited to determining whether science works. Investors also need to understand the route to a commercial product, which milestones reduce the largest risks, what capabilities are still missing from the team and what the next round of capital is expected to unlock.
Constructor Start also widens the network around participating companies. During the program, Constructor Capital introduces founders to other VCs, technical experts and companies in its portfolio or pipeline that may be relevant partners. Marie Lepske said the wider network includes co-investors, entrepreneurs and mentors who may also become interested in participating companies.
Constructor Capital has already invested in companies from previous Constructor Start cohorts. Marie said the fund is also considering several companies from earlier cohorts that did not win at Demo Day, in some cases at later stages.
For founders, Constructor Start provides a concentrated environment for testing the commercial case around technically complex products and building investor relationships. For Constructor Capital, it creates an earlier view of companies that fit its investment focus and more evidence on how the teams behind them execute.
Applications are now open for Constructor Start Batch 5, a global, equity-free 10-week program for DeepTech and Software founders. Participants work with investors, technology executives and domain experts to validate their market, sharpen their commercialization and go-to-market strategy, build a path to pilots and early customers, and become investment-ready. Selected teams also gain access to Constructor University’s research and industry ecosystem, with funding opportunities, including investment opportunity from Constructor Capital.
We look forward to seeing you in Bremen.
