

Amaury Martiny
Verified Expert in Engineering
Full-stack Developer
Amaury is a certified senior Toptal blockchain engineer, working as a protocol developer on the Cosmos SDK. Previously, he spent three years focusing on core development on Polkadot, Substrate, and Ethereum. Amaury is interested in entrepreneurship and has worked for startups of various sizes. He reads a variety of subjects, such as mathematics, history, and philosophy, in his spare time.
Portfolio
Experience
Availability
Preferred Environment
Blockchain, Parity Polkadot, Cosmos, Ethereum
The most amazing...
...project I've built was a mobile app that got featured on NBC and BBC with 100k+ users. It was built in one weekend!
Work Experience
Senior Software Engineer | Cosmos Core Developer
Regen 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.
Software Engineer
Parity 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.
Full-stack Developer
Eighttails
- 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.
Full-stack Developer
Fieldbook
- 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.
Lead iOS Engineer
Zelos (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.
Lead Front-end Engineer
MonBanquet
- 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.
Software Engineer
Feedly
- 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.
Cloud Computing Intern
IBM
- 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.
Linux Adminstrator
VIA 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.
Experience
Sh**t! I Smoke
https://shootismoke.appTechnologies: React Native
Reacher
https://reacher.emailFeedly Mini
In The Loop
My group won first prize at the hackathon.
Skills
Languages
JavaScript, HTML5, CSS3, TypeScript, Go, GraphQL, Rust
Frameworks
Redux, Next.js, Electron, Parity Polkadot, React Native
Libraries/APIs
MobX, Node.js, React, Web3.js, REST APIs, RxJS, Protobuf
Tools
Git
Platforms
Blockchain, Ethereum, Linux, Docker, Kubernetes
Other
DApps, Chrome Extensions, Cryptocurrency, Open Source, Smart Contracts, Cosmos, Substrate, WebAssembly
Storage
MongoDB, PostgreSQL, MySQL
Education
Master of Science (Double) Degree in Computer Science
Wrocław University of Science and Technology - Wrocław, Poland
Master of Engineering (Double) Degree in Engineering and Management
Ecole Centrale Paris - Paris, France
Certifications
Machine Learning Course Certification
Stanford University via Coursera