Senior Software Engineer | Cosmos Core Developer
2020 - PRESENTRegen Network- Maintained the Cosmos SDK, a framework powering the $100B Cosmos blockchain ecosystem, as a core protocol developer.
- Led two working groups of four people on introducing features on the Cosmos SDK, from design and specification to implementation, quality assurance, and release.
- Refactored the 200K-line Cosmos SDK by introducing Protobuf as the default encoding while maintaining backward compatibility.
Technologies: Blockchain, Go, Cosmos, TypeScript, Docker, DApps, Protobuf, CryptocurrencySoftware Engineer
2017 - 2020Parity Technologies- Headed the development of a proof-of-concept crypto wallet running a Polkadot light client in WebAssembly inside the browser.
- Refactored Polkadot.js (100,000 lines of code), the official TypeScript SDK on top of Polkadot and Substrate, into a more modular architecture with dynamically-generated TypeScript typings.
- Created and launched Fether, the first Ethereum wallet on top of a light client, totaling 5,000 downloads after one year.
- Designed and completed Light.js, a high-level reactive library optimized for light clients and an alternative to Web3.js.
- Presented talks about Web3.js, DApp development, and light clients.
- Cooperated with security firms on auditing the Polkadot.js codebase.
- Integrated the low-level in-house codec, SCALE codec, into the Polkadot.js codebase.
Technologies: DApps, TypeScript, Ethereum, Parity Polkadot, Rust, Blockchain, WebAssembly, React, Open Source, Web3.js, Chrome Extensions, Kubernetes, Smart Contracts, Substrates, Electron, DockerFull-stack Developer
2017 - 2017Eighttails- Led the development of a RESTful Express server that connected to the Ethereum blockchain using web3.js.
- Architected and developed an innovative one-click, cryptographically-secure login flow using the MetaMask extension. See the associated article on Toptal Blog: Toptal.com/ethereum/one-click-login-flows-a-metamask-tutorial.
- Wrote tests that covered 98% of the codebase and set up a git-based continuous integration using CircleCI, which deployed staging and production versions to AWS.
- Built the front-end web app skeleton using React and Redux and delegated further front-end development to a junior developer.
Technologies: Amazon Web Services (AWS), MongoDB, React, Node.js, Web3.js, Ethereum, DApps, Blockchain, TypeScript, CSS3, PostgreSQLFull-stack Developer
2017 - 2017Fieldbook- Emphasized UX by paying extra attention to details, as UX is one of Fieldbook's strengths.
- Participated in the team-wide project of shipping version 2.0 of the product, working under high pressure for the whole month preceding the launch.
- Collaborated with the product owner, developers, and QA engineers in an agile environment.
- Wrote at least one line of test for each line of code.
Technologies: MongoDB, PostgreSQL, Express.js, Backbone.js, REST APIs, MySQLLead iOS Engineer
2017 - 2017Zelos (via Toptal)- Reorganized the code by introducing the Ducks architecture for Redux, increasing the readability and maintainability of the codebase.
- Transitioned from REST API calls to GraphQL queries, optimizing network payloads, especially for low-bandwidth mobile phones.
- Created a customizable three-part screen component for an innovative UX, with a new way of navigating between screens.
Technologies: GraphQL, Redux, React Native, MobXLead Front-end Engineer
2016 - 2016MonBanquet- Completely redesigned the landing page—resulting in a 30% conversion rate increase.
- Built from scratch, the back-office led to a huge productivity boost compared to the previous Trello-based system.
- Assembled build tools (Gulp, Jenkins) to automate and optimize website building, testing, and deployment.
- Conducted A/B testing on landing page features to obtain the highest conversion rate.
Technologies: AngularSoftware Engineer
2014 - 2014Feedly- Created from scratch a Chrome extension for bookmarking; it was rated five stars and used by 250,000 users in the Google Chrome Store.
- Led the development of the Feedly macOS app. While the app itself consisted only of a WebView wrapper over the main website, I implemented multiple features for a native-like user experience.
- Built a prototype of SimpleFollow.org—an easy way to add RSS feeds to your favorite news aggregator.
- Worked closely with the designers to implement new UI/UX features on the main page feedly.com.
Technologies: Django, Objective-C, JavaScript, Chrome Extensions, HTML5Cloud Computing Intern
2013 - 2013IBM- Conceived and implemented tailored IaaS solutions for client companies such as Danone and Gemalto using VMware.
- Optimized the virtual machine creation process, reducing the VM installation time from eight hours to 45 minutes.
- Created a UI for following in real-time the VM creation process.
- Documented the VM creation tool usage guide in detail, both for end-users and developers.
Technologies: JavaScript, Perl, VMwareLinux Adminstrator
2011 - 2013VIA Centrale Réseaux- Oversaw the whole network at the university campus with 6,000 connected devices.
- Managed a five-person team on a Linux server administration (Apache, Postfix, BIND, and virtualization).
- Built from scratch the local Facebook of the university, using Symfony 2, PostgreSQL, and jQuery; it had 3,000 daily active users.
- Launched an ICEcast radio streaming platform for the university.
Technologies: Virtualization, Linux Server Administration, Linux