Writer · Smart Contract Auditor · Kyiv
Khrystyna Marchenko
A Ukrainian smart contract auditor based in Kyiv. The better part of a decade reviewing DeFi protocols and writing reports that were sometimes read in time.
About
Khrystyna "Khrys" Marchenko is a Ukrainian smart contract auditor based in Kyiv. She has spent the better part of a decade auditing DeFi protocols, cross-chain bridges, and the financial primitives stacked on top of them. Before crypto, she wrote Java for European banks; she does not consider this a coincidence.
Her work has informed post-mortems at protocols she will not name and methodology notes at firms she will not name either. She prefers to let the reports speak for themselves.
She has lived in Kyiv through the full course of the war. Continuity is a record of the working life she has continued through it — and of the city, the conversations, and the losses that have surrounded it. The book is forthcoming.
Career
Smart contract auditor with eight years in Web3, preceded by three years of enterprise Java in banking. Focus on Ethereum and EVM-compatible chains: DeFi protocols, cross-chain bridges, lending markets, and the assorted financial primitives glued together on top of them.
Practice
Independent auditor since 2023, working through audit collectives and contests. Earlier: a senior auditor role at a Kyiv firm; before that, a stealth Web3 startup; before that, backend Java on a long engagement with a European private bank.
Approach
Manual review, exploit prototyping, fuzzing, symbolic execution, light formal verification. A strong preference for high-rigor written reports over the marketing-grade kind.
Education
MSc in Software Engineering and BSc in Computer Science from Igor Sikorsky Kyiv Polytechnic Institute. Thesis on static analysis of concurrent programs — useful priming, in retrospect, for Solidity.
Languages
Ukrainian (native), Russian (native), English (C1), Polish (working), German (rusty).
Book
Writing
The pieces I post are the things I can say in print that I cannot say in a client deliverable. They are about how crypto actually works under the hood — which is to say, how the people who build it actually behave when no one is watching, and how the math holds up only as long as the people do.
A few things this is not. It is not investment advice; I would be embarrassed to give any. It is not a chronicle of "the space," which is large enough now that no one person can chronicle it honestly. It is not, despite appearances, cynical — I still think the cryptography is beautiful. The social layer is the part I keep writing about.
— Khrys
Support
If anything here has been useful to you, the addresses below are open. Tips are not solicited; they are appreciated when offered.
0xfB778Efd06275516272B525BC61BC1116a5eb632
bc1qaq4rgd8kj7eczeef3yawm2h9mrcqtecfp8cvdl
Contact
For correspondence: Khrystyna@alphaseeq.com. I read everything and reply to roughly one in three messages, mostly because of bandwidth and slightly out of principle.
If you are a journalist: I am not your source. If you are a founder whose protocol I have audited: please do not try to guess.