Ukrainian accelerator Defence Builder has started accepting applications for the fourth batch for developers of defense technologies and dual-use solutions. The program is designed for ten teams that will prepare their developments for scaling for four months under the guidance of the military, experts and investors.
Ukrainian accelerator Defence Builder has started accepting applications for the fourth batch for developers of defense technologies and dual-use solutions. The program is designed for ten teams that will prepare their developments for scaling for four months under the guidance of the military, experts and investors.
The accelerator team told AIN that the application deadline is October 30, 2026, and the course will start in November.
Developers from any country in the world who have a ready-made working prototype of the TRL 4+ level — from software and individual components to complex systems — can participate in the program. In Batch 4.0, priority will be given to projects in the areas of multi-layered protection against air threats (including CABs), persistent communications and navigation, autonomous drones, robotic complexes and modules for existing platforms.
The training will be held in a hybrid format in Ukrainian and English. The program consists of military and business tracks. Within the military block, teams will test solutions together with more than 30 military units. The business part includes consultations from more than 80 experts in unit economics, intellectual property, exports and capital raising with access to a network of more than 100 investors. Also, this batch will feature a separate AI track for R&D and operations.
Each selected company will receive a starting grant in exchange for a minority stake, and based on the results of the work, it will be able to attract additional funds from partners. Among the mentors of the fourth set are Oleksandr Kharkovets, commander of the ground robotic complexes battalion of the 93rd Kholodny Yar brigade, DeepState co-founder Roman Pohoriliy, CEO Buntar Aerospace Ivan Kaunov, and former head of the NATO DIANA program Vijay Sekhara.
Earlier, in the spring of 2026, Defence Builder, founded by Sigma Software, KSE and Buntar Aerospace, announced its expansion from an accelerator to a full-fledged Defense Tech ecosystem. In addition to educational programs, it included its own $5 million venture fund, DB Fund, as well as areas of market analytics, deal support, due diligence and corporate governance.
Since its launch in 2024, the accelerator has graduated three batches of 24 companies from Ukraine, Estonia, Denmark, Canada, and the UK, raising a total of over $650,000 in grant funding. Following Demo Day 3.0 in June 2026, the most successful DefTech teams received up to $65,000 in support from the ecosystem and partners.
