Our mission
Built after losing funds to a chain-mismatch drain we should have been able to prevent.
CEO & Co-Founder
Ozcan Aytas
Before Defimec, Ozcan built payment and transaction-routing infrastructure for early-stage fintech companies in Istanbul and across Europe — the kind of work where failure modes and verification logic are the whole job. That background is precisely what Defimec applies to the signing layer: treat every RPC response as untrusted input until proven otherwise.
By 2019 he was trading seriously across Ethereum and emerging L2 ecosystems. In 2021 a stale RPC on an Arbitrum config triggered the chain-mismatch drain that started the company. "Nothing in the signing path verified the chain before asking the hardware device to sign. The wallet couldn't know. The Ledger couldn't know. That was the gap." That observation is the entire product.
He runs Defimec from Levent, Istanbul — Buyukdere Caddesi, the street that houses most of Turkey's active financial infrastructure. Four people. No outside money.
The team
Small by design
Bootstrapped means lean. Four people — close to the protocol layer and to the traders using it. No management layer between an engineer and the problem.
Mert Kaplan
Head of Engineering
Selin Yıldız
Protocol Engineer
Arda Çelik
Product Designer
How we work
Three things we don't compromise on
Verifiable
Don't trust, verify. The same principle that drives the product — RPC health, chain ID, calldata integrity — drives how we run the company. No marketing claims we can't technically back up.
Minimal
One signing surface. Not a wallet. Not a DEX aggregator. Not an NFT marketplace. The product scope is deliberately narrow because the narrow problem is the important one to solve correctly.
Independent
Bootstrapped since 2021. No investor pressure to "growth hack" our way to false metrics. Pricing is set to sustain a small team in Istanbul, not to chase an ARR target on a VC timeline. The product roadmap is driven by trader problems — not by what makes a good deck slide.
Join the team
We hire rarely. When we do, it's for this.
Roles close to the protocol layer — signing relay internals, RPC health probe logic, or the kind of UX that makes a hardware-signing workflow feel like it has no friction at all. If that's the work you want to do, write to Ozcan directly. No recruiters.
Contact Ozcan directly