Roman is available for hire
Hire RomanRoman Cirier
Verified Expert in Engineering
React Developer
Location
Beijing, China
Toptal Member Since
August 17, 2022
Roman has conceptualized and developed many applications from ideas into products, and he was a lead developer on an application similar to Discord. He is passionate about programming robust architecture for applications, working mainly with React, React Native, and Node.js in TypeScript. He designs user-friendly interfaces with smooth animations. Roman's industry experience is backed by a dual master's degree in computer science and engineering.
Portfolio
Mayoo
Node.js, NestJS, PostgreSQL, Microservices, React, React Native, TypeScript...
Snoop Media
React Native, TypeScript, Expo, Styled-components, React Apollo, GraphQL...
sGuiding
React Native, TypeScript, Redux, Axios, Location Tracking, Audio, Sentry...
Experience
Availability
Part-time
Preferred Environment
Jira, Visual Studio Code (VS Code), MacOS, GitHub
The most amazing...
...product I've developed is Lanslot, a social app for gamers ranked among France's top 10 social media apps for iOS and Android.
Work Experience
Architect | Full-stack Developer
2023 - 2024
Mayoo
- Designed the architecture of the project, the data models, and programs with their technologies.
- Developed a REST API from scratch with microservices in Node.js, NestJS, Prisma, and TypeScript.
- Built a mobile application from scratch with React Native and TypeScript.
- Created a web application from scratch with React and TypeScript.
- Dockerized and deployed the applications with automatic pipelines.
Technologies: Node.js, NestJS, PostgreSQL, Microservices, React, React Native, TypeScript, Deployment, DigitalOcean, Expo, Prisma, CSS, HTML5, User Interface (UI)
Front-end Developer
2022 - 2023
Snoop Media
- Developed new screens for the application with high performances and a clean codebase split into components using the Atomic Design methodology.
- Developed a real-time messaging screen with a custom bidirectional infinite list. Organized the architecture to share the common code between the chat and the comments. Integrated standard chat features such as editing, deleting, and liking.
- Integrated new, generic components that are fully customizable, strongly typed, and with tests.
- Developed new features for the dashboard made in React, such as charts using ApexCharts.js to visualize the application metrics and other pages to manage the product.
- Developed a brand new discovery part of the application organized with tabs containing sections of items, combined with a search area for complementary needs. Worked on maintaining good performances while having to display that amount of data.
- Fixed issues on existing features, responsiveness, architecture design, and animation performances as the application were getting ready to be released for the beta.
- Integrated analytics frameworks such as Firebase Analytics, UXCam, and Amplitude. Built a common interface for them to speed up the integration.
- Worked on optimizing the cache to improve the loading time.
- Integrated basic mobile application features such as custom in-app notifications.
Technologies: React Native, TypeScript, Expo, Styled-components, React Apollo, GraphQL, UI Animation, Redux, Context API, Figma, Mobile App Development, Sentry, Responsive, Android, iOS, Clean Architecture, Atomic Design, Mobile Apps, Segment, Firebase Analytics, Amplitude, UXCam, Realtime, WebSockets, Docker, Amazon Web Services (AWS), Mobile, ApexCharts.js, React, Web & Mobile Applications, Full-stack Development, Full-stack, Cross-platform, API Integration, App Development, Cross-platform App Development, Mobile Architecture, Jest, Architecture, Mobile Development, User Interface (UI)
Mobile Developer
2022 - 2022
sGuiding
- Created a React Native application from scratch in TypeScript with Redux, Axios, and other dependencies.
- Developed a map using the Google Maps SDK to display the sites and itineraries around the user's location.
- Created a step-by-step mode to visit the different sites of an itinerary, showing the itinerary to follow on the map and playing the site's audio whenever the user arrives.
- Developed a service to play audio guides, regardless of whether the app is in the background or foreground.
- Built a background service that searches and plays audio of sites near the user without taking any specific action.
- Created screens to discover or browse through the sites, itineraries, packages, and other related features.
- Developed basic features, including authentication, app settings, and caching.
Technologies: React Native, TypeScript, Redux, Axios, Location Tracking, Audio, Sentry, Google Maps SDK, Mobile App Development, Mobile Apps, Front-end Development, Audio Streaming, Mobile, Cross-platform, API Integration, App Development, REST APIs, Cross-platform App Development, Mobile Architecture, Architecture, Mobile Development, Google Maps, User Interface (UI)
Mobile Developer
2022 - 2022
Bloomflow
- Implemented a business card scanner with text recognition using Google's ML Kit.
- Updated the application framework and dependencies and fixed crashes and broken features.
- Reworked the UI and navigation flow of multiple screens to add a company and other design updates in the application.
- Developed a swipe animation for switching screens to provide a better user experience.
Technologies: React Native, Redux, OCR, ML Kit, Sentry, Fastlane, Loopback, JavaScript, Mobile App Development, Mobile Apps, Styled-components, Front-end Development, Mobile, Cross-platform, App Development, REST APIs, Cross-platform App Development, Swift, Mobile Development, User Interface (UI)
Lead Mobile Developer
2020 - 2022
Lanslot
- Led the development and release of the application in stores and designed features with the product owner and lead back-end developer.
- Developed vocal channels (VoIP using WebRTC), real-time chat (using WebSockets), and dynamic feed (a simple implementation of server-side rendering).
- Managed and reviewed developers' code and assisted in developing new features.
- Developed a robust architecture with a caching system to share common data between screens and optimized the network calls.
- Created a clean and organized structure for the application with a UI library full of customizable components.
- Developed smooth animations and transitions, running at 60 frames per second on low-end devices.
- Developed end-to-end tests to avoid regression on new releases.
Technologies: React Native, TypeScript, GitLab CI/CD, Firebase, WebRTC, GraphQL, React Apollo, WebSockets, Fastlane, CodePush, Redux, Java, Objective-C, Jira, Adobe Experience Design (XD), Lottie, Mobile App Development, Mobile Apps, E2E Testing, Styled-components, Front-end Development, Mobile, Web & Mobile Applications, Cross-platform, API Integration, App Development, Cross-platform App Development, Mobile Architecture, Jest, APIs, Architecture, Mobile Development, Detox, VoIP, User Interface (UI)
Web Developer
2020 - 2020
EDGCo
- Developed a calendar mode for EchoApp to visualize and organize tasks over time.
- Optimized data flow in Redux-Saga and, more generally, over the entire application and through each screen.
- Refactored the web application to be responsive to different screen sizes.
- Developed new features to organize and regroup tasks, such as workspaces and tags.
Technologies: React, TypeScript, Redux, Docker, Front-end Development, Web Development, API Integration, App Development, REST APIs, Redux Thunk, HTML5
Full-stack Developer
2019 - 2020
EDGCo
- Developed new features for CryptoBot, such as manual trading between wallets on different platforms and buying and selling cryptocurrencies.
- Created new charts and graphs for the web application to analyze the performance.
- Optimized the Node.js programs in charge of synchronizing the price of the market.
- Developed new features for creating and adding a bot on the web application.
- Built a new Node.js program to handle notifications and added desktop notification settings to the web application.
Technologies: Node.js, React, TypeScript, Docker, Redux, WebSockets, Redis, Full-stack Development, Front-end Development, Back-end Development, Full-stack, API Integration, App Development, APIs, REST APIs, Redux Thunk
Full-stack Developer
2019 - 2019
EDGCo
- Developed Ostyle from scratch—a web application with responsive designs where users can select different styles of clothes and customize them.
- Developed a REST API using Strapi with a database.
- Built a process for users to buy and pay for items in their cart (using Stripe) and then generate orders.
Technologies: React, Redux, TypeScript, Node.js, PostgreSQL, Stripe, Docker, Front-end Development, Full-stack Development, Back-end Development, Full-stack, API Integration, App Development, APIs, REST APIs, Stripe Payments, Redux Thunk
Experience
Kleos
https://apps.apple.com/be/app/6443931092Kleos is a fitness application to plan and log your workouts and analyze your progress through your journey. I used this project to learn new skills and try architectures and dependencies.
ACCOMPLISHMENTS
• Designed elegant interfaces on Figma, matching with a theme I created.
• Developed the applications with React Native and Expo.
• Built the application with Watermelon DB (based on SQLite) to store all workout data.
• Developed complex animations and transitions with Reanimated and SKIA.
• Designed the store's pages and descriptions and released the application.
ACCOMPLISHMENTS
• Designed elegant interfaces on Figma, matching with a theme I created.
• Developed the applications with React Native and Expo.
• Built the application with Watermelon DB (based on SQLite) to store all workout data.
• Developed complex animations and transitions with Reanimated and SKIA.
• Designed the store's pages and descriptions and released the application.
React Native Bottom Modal
https://github.com/Nazort/react-native-bottom-modal-scrollableA bottom modal component I developed using React Native Gesture Handler and React Native Reanimated 2. I developed this for some of my own projects and made it available on npm. I expanded my animation capabilities while developing this project.
Emoleaks
Emoleaks is an application to help content producers test their media (such as ads) on groups of testers using AI. On the web application, the tester can watch the content while being analyzed by an AI to detect the emotions felt so that the producer can know if the content creates the desired effect on potential customers before publishing the content. I mainly worked on the API and the web application of the product.
Skills
Languages
JavaScript, TypeScript, GraphQL, SQL, CSS, HTML5, C, C++, C#, Java, Objective-C, Swift
Frameworks
React Native, Redux, Realtime, Detox, NestJS, Express.js, Loopback, Jest
Libraries/APIs
Node.js, React, Redux-Saga, Context API, REST APIs, Google Maps, WebRTC, Google Maps SDK, Stripe, Skia, ApexCharts.js
Paradigms
Cross-platform, App Development, Mobile Development, E2E Testing, Responsive, Microservices, Scrum, Clean Architecture, Mobile App Design
Platforms
MacOS, Firebase, Visual Studio Code (VS Code), Mobile, Android, iOS, Docker, Amazon Web Services (AWS), DigitalOcean
Other
Mobile Apps, Styled-components, Mobile App Development, Front-end Development, Full-stack Development, Full-stack, Cross-platform App Development, API Integration, Software Architecture, WebSockets, Axios, Apollo, Design, UI Animation, Lottie, Web Development, Back-end Development, Web & Mobile Applications, APIs, Software Engineering, Mobile Architecture, Architecture, VoIP, Deployment, User Interface (UI), CodePush, OCR, ML Kit, Location Tracking, Audio, Atomic Design, Segment, Amplitude, UXCam, Audio Streaming, Stripe Payments
Tools
GitLab, GitHub, Slack, Zsh, Xcode, React Apollo, Sentry, Figma, Adobe Experience Design (XD), Expo, Firebase Analytics, Redux Thunk, Prisma, Jira, GitLab CI/CD, Fastlane, Google Places SDK
Storage
Redis, PostgreSQL, MongoDB, SQLite
Education
2018 - 2020
Dual Master's Degree in Computer Engineering
Beijing Jiaotong University - Beijing, China
2015 - 2020
Dual Master's Degree in Computer Science
Epitech - Paris, France
2015 - 2018
Bachelor's Degree in Computer Science
Epitech - Nantes, France
Collaboration That Works
How to Work with Toptal
Toptal matches you directly with global industry experts from our network in hours—not weeks or months.
1
Share your needs
Discuss your requirements and refine your scope in a call with a Toptal domain expert.
2
Choose your talent
Get a short list of expertly matched talent within 24 hours to review, interview, and choose from.
3
Start your risk-free talent trial
Work with your chosen talent on a trial basis for up to two weeks. Pay only if you decide to hire them.
Top talent is in high demand.
Start hiring