
Dominik Krížo
Verified Expert in Engineering
Software Developer
Likavka, Žilina Region, Slovakia
Toptal member since August 9, 2021
Dominik is an elite blockchain security researcher and bounty hunter with consistent top placements in audit competitions and high-value bug bounties on Immunefi. Specializing in Solana and Rust-based protocols, he has identified critical vulnerabilities across DeFi platforms, smart contracts, and blockchain infrastructure. His transition from blockchain development to security research provides unique insight into both building and breaking protocols.
Portfolio
Experience
- Algorithms - 12 years
- Solidity - 5 years
- Smart Contracts - 5 years
- Rust - 5 years
- Object-oriented Programming (OOP) - 5 years
- Ethereum Smart Contracts - 5 years
- Security Research - 3 years
- Blockchain - 3 years
Preferred Environment
Visual Studio Code (VS Code), MacOS
The most amazing...
...discovery was uncovering a high-severity exploit in a major liquid staking protocol that would have eliminated millions in revenue daily.
Work Experience
Blockchain Security Researcher
Naaka Studio
- Secured 1st place in competitive audits across multiple platforms, including Cantina, Sherlock, Hacken, and Hats Finance, consistently ranking in top positions against global security researchers.
- Identified critical vulnerabilities in major DeFi protocols, including AAVE, Reserve, Tensor, and cross-chain infrastructure worth billions in total value locked.
- Conducted 10+ private security reviews for protocols across Solana, Ethereum, Substrate, and ink! ecosystems through collaborations with Spearbit, Zenith, and Sherlock.
- Uncovered critical bugs through bug bounty programs, preventing potential exploits in production protocols handling significant user funds.
Head of Engineering
727 Ventures
- Oversaw grant deliveries of our infrastructure products and managed developers working on our products.
- Developed an application that transpiles Solidity code into ink! code.
- Spoke at the sub0 developer conference about our infrastructure products.
- Led the auditing team during the auditing of an ink! smart contract application of an NFT marketplace based on the Aleph Zero blockchain.
- Provided support to users learning more about ink! smart contracts ecosystem.
- Conducted an audit of a decentralized exchange based on the Aleph Zero blockchain and ink! smart contract language.
Collaboration Lead
Supercolony
- Led a collaboration between my company and partner company, including project and partnership management.
- Worked on transforming a lending platform from Solidity to ink!.
- Led developers in the development, testing, and delivery of two applications.
Senior Blockchain Engineer
Supercolony
- Worked on transforming a big decentralized exchange from Solidity language to ink! WASM smart contract language on Rust.
- Made a huge contribution to OpenBrush, the standard library for ink! WASM smart contracts on Rust.
- Came up with and created Sol2Ink, a transpiler based on Rust, which transpiles Solidity code to ink! code.
Android Developer
DOXXbet & K-BET, sro
- Participated in transforming legacy codebase from Java to Kotlin.
- Took part in transforming an old UI to a new UI that's more user-friendly.
- Wrote code for transferring user data from app to server and vice versa via REST API.
Programmer
PROSOFT spol s.r.o.
- Developed an application used by the Slovak national railway company to manage employees' attendance and issue and verify travel tickets.
- Wrote unit tests for features and fixed bugs found by the unit tests.
- Played a key role in delivering the MVP of the application on time to the customer for testing without any critical issues. This required working many extra hours.
- Wrote back end for the application server to synchronize user local data with the server in Jakarta EE, utilizing Java server module.
Programmer
PROSOFT spol s.r.o.
- Developed an Android app, written in C++ using Qt, that engine drivers in railway companies use to track their work, including what they did on their shift, note if something went wrong in their train, and keep track of train inventory.
- Worked on the front end of the Android application, using QML.
- Connected the front end with database data by writing SQL queries based on technical analysis done by the analyst.
Experience
Sol2Ink – Solidity Code Transpiler to ink!
https://github.com/727-Ventures/sol2inkOpenBrush - ink! Smart Contract Library
https://github.com/727-Ventures/openbrush-contractsAndroid Betting App
https://www.doxxbet.sk/skAndroid App for Slovak National Railway Company
Utilizing Advanced Data Structures
https://github.com/coreggon11/data-structures-2/tree/mainThe first project focused on RAM efficiency, applying a K-Dimensional tree to determine how many keys each node had. Nodes were then compared by the key based on the level of the actual node being compared. The second project focused on storing large amounts of data, for example, in databases, so it aimed at disk efficiency using extensible hashing. Data was stored in the structure with keys, which were translated to hash and stored in the corresponding blocks in memory. If the blocks were full, they were stored in a congesting file.
School Project for Swapping Courses Between Students
Education
Bachelor's Degree in Informatics
University of Žilina - Žilina, Slovakia
Skills
Libraries/APIs
Node.js, REST APIs, RxJava, jQuery, React
Tools
Android Studio, Git, GitLab, Jira, Gradle, GitHub, Slack, Jenkins, Redmine, Unity 5, Java Application Servers, CMake
Languages
C++, Java 8, Kotlin, Solidity, Java, C#, UML, Rust, TypeScript, SQL, JavaScript, QML, C#.NET, PHP, CSS, Assembly
Frameworks
Android SDK, Parity Polkadot, Qt, Dagger, Unity, Unity3D
Paradigms
Agile, Scrum, Unit Testing, Mobile Development, Object-oriented Programming (OOP), Refactoring, Management, Model View ViewModel (MVVM), REST
Platforms
Windows, Android, Blockchain, Ethereum, Mobile, MacOS, Firebase, Visual Studio Code (VS Code), Java EE (Jakarta EE), Linux, Docker, Web
Storage
JSON, MySQL, SQLite, Oracle SQL, Sybase, Databases, Relational Databases
Other
OOP Designs, Algorithms, Data Structures, Bug Fixes, Crypto, Mobile App Development, Coroutines, Back-end, Decentralized Finance (DeFi), CI/CD Pipelines, Large-scale Projects, Lambda Functions, Programming, Full-stack, Debugging, Smart Contracts, Ethereum Smart Contracts, Cryptocurrency, Architecture, Non-fungible Tokens (NFT), Minimum Viable Product (MVP), Gaming, ERC-20, ERC-721, Mobile Apps, WebAssembly (Wasm), Audits, Security Research, Bug Bounty Program, Web Development, APIs, Game Development, Client/Server Networking, Artificial Intelligence (AI), Machine Learning, Multithreading
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