The op-ed by the Director of the Defence Builder Accelerator describes the checks the accelerator runs with teams during selection and the programme, and which Batch 4.0 participants will work through from November.
Yana Shkvarovska, Director of the Defence Builder Accelerator, has published an op-ed on LB.ua on what a defence-tech team should verify before it commits months of development to a product. The text grew out of the first workshop of Validated & Fundable, a series Defence Builder runs together with European Defense Tech, and out of a case from the selection for Batch 3.0.
In that case, a team came to the accelerator with a solution it had started building as volunteers, when units had a real need for it. By the third year of the full-scale war the team wanted to grow, but an assessment of its work and of the market showed that this product had limited room to develop. Defence Builder looked at the team’s technical expertise and the problems it could still solve, discussed options with the founders and military experts, and proposed a different direction that matched current needs. The team changed its product focus, went through the initial stages of development and, at the time of writing, was testing first samples with the military and potential integrators.
The op-ed turns that experience into a sequence of checks. The first is to start with the problem rather than the technology: ask military users to describe a specific recent case from start to finish, and hear from several people, because a commander, an operator and a repair workshop each see a different part of the system. The second is to weigh the evidence, since a manufacturer’s claim, a demo, feedback from a unit and an independent assessment carry different weight, and a mention in a catalogue or participation in a programme proves nothing on its own. The third is to count the full cost of use: deployment, training, spare parts, repair and integration with the systems a unit already runs come on top of the price. The fourth is to know who decides, because the person who uses a product, the person who integrates it and the person who approves the purchase value different things. The fifth is to record, alongside the hypothesis, the conditions under which it would prove wrong, and to check the direction before development rather than after it.
Each of these checks is built into the accelerator programme. Batch 4.0 teams test their products with active military units and receive direct feedback from operators. Test results are documented in full, so a team leaves with evidence that procurement bodies and investors can rely on. In the venture track, teams work through unit economics and procurement pathways with mentors and meet procurement officers, investors and defence operators. More than 30 mentors with defence and venture backgrounds help teams test their hypotheses and change focus when needs change, as the team described in the op-ed did.
Batch 4.0 is open to companies with a working prototype, from pre-seed to Series A, in UAS, counter-UAS, C2, EW and situational awareness. Applications close on 30 October 2026, and the programme starts in November.
Programme details: https://defencebuilder.com/batch4
Apply: https://defencebuilder.com/batch4-application-form
