The recent DefHack: Resilience edition hackathon in Tallinn, Estonia was all about extendability. Builders and startups showed off interesting projects in areas like sustainability in defence, ideas that touch the everyday person and the average community and the role they play in defence. Signal jamming, civilian crisis response, thermal camouflage, and disinformation all took stage.
The 48-hour hackathon was organised by the Ministry of Defence of Estonia, the Estonian Business School and clean tech accelerator Beamline. The theme was resilience and start-ups and projects were to be “innovative solutions for material reuse, circular supply chain design, product redesign, and environmentally sustainable disposal methods in the defence sector.”
But in one significant way, it was not your typical hackathon: many of the 12 teams were preloaded with ideas and populated with members counting years of experience at dual-use companies.
(Disclosure: Resilience Media was a proud media partner of the event.)
Kodus, a platform to prepare civilians for wartime by training for ‘resilience’ among communities, caught the eye of Darkstar’s Kasper Gering.
“I especially liked this team as what they are doing is exactly right,” he said. “We already have our defence forces and our defence league with established roles for wartime, but what Kodus is doing is adding an extra layer on top, because we have lots of people who have a strong will to defend.”
He said that there was a study commissioned recently in Estonia where 62% of the population said they are willing to participate in defence activities. Specifically, 12% in direct military roles, 23% in supportive roles to military (e.g., rear-area support, logistics, etc.), and 26% in non-military defence activities (e.g., the medical field or organizing evacuations). Also, a whopping 82% of the population considers armed resistance necessary in the event of an attack. “So there really is an untapped resource,” he added.
Gering was joined on the jury by Major General Ilmar Tamm, Commander of the Estonian Defence League; Lieutenant Colonel Asso Treksler, Commander of the Logistics Battalion at the Estonian Defence Forces; and Mart Habakuk, Chancellor of Estonian Business School.
Jälle Technologies, the overall winners of the event, brought a very interesting project to life over the weekend. Already established in the climate tech space, Jälle recycles materials from batteries (the name means “again” in Estonian). Founded in 2023 the start-up recently raised a €2 million funding round that included funding from Kiilto Ventures and 2C Ventures, angel investment and grants from Enterprise Estonia (EIS) and the Environmental Investment Centre (KIK)
The EU is aiming for a 70% recycling efficiency to be achieved by recyclers of lithium-based batteries by 31 December 2030. Jälle Technologies is tackling the problem by transforming used batteries into reusable and sustainable metals and graphene-like materials.
During the hackathon, this graphene was used to prove its efficiency in reducing thermal energy detection when applied to clothing.
With its focus coating a piece of army apparel material, Jälle focused on four main categories: thermal camouflaging, electromagnetic interference, shielding, and strength of material. Impressing the jury with the initial results, they walked away with the top spoils which included €1,000 worth of legal advice, tickets to EstMil.tech 2026 and a plan to tackle the breathability of the coated material.
“We’ll be looking into actually electro spinning our carbon material into a fibre,” said Eriki Ani, the CEO.
Among the other projects under construction during the hackathon were Swiss drone company Avientus, which has developed a quiet electric drone aimed at delivering supplies to challenging areas.
Considering a move to Estonia to get involved in defence due to the Swiss neutrality laws, Avientus is now set up. Part of the second place prize they collected is office space in Tallinn.
Other notable projects included LessonLock, an offline reporting system that delivers lessons from the frontline; ResilientMesh, a dual-use, device-agnostic, low-cost, AI-driven mesh network for disaster or wartime environments; EDIE Estonian Defence Innovation Exchange for defence procurement; and Trinode Systems, which is building customized AI solutions to enhance decision-making, automate workflows, and improve operational efficiency.









