Rareș – Rust, Vue.js, Docker

Building and launching SaaS products independently, handling the entire product lifecycle from ideation and architecture through deployment, billing, and user support. Applications are built with Nuxt/Vue.js frontends and Cloudflare Workers for serverless backends, with Stripe handling subscription billing.

• Designed and created full-stack SaaS applications as a solo developer from scratch
• Integrated Stripe subscription billing with tiered pricing plans, webhook handling, and payment flow management
• Built authentication systems and serverless API infrastructure on Cloudflare Workers
• Managed full product lifecycle: ideation, architecture, development, deployment, monitoring, and iteration

A real-time financial data infrastructure platform for the Sui blockchain. It indexes trading events from Sui DeepBook V3 (a central limit order book DEX) and serves processed market data through REST APIs and real-time SSE streams. The platform targets traders, analytics tools, and DeFi applications that need sub-second access to order book data, OHLCV candles, and live trade feeds.

• Designed and built the whole system from scratch: blockchain indexer based on Sui indexer alt framework, data pipeline, NestJs REST API, and real-time streaming layer processing 1,000+ trading events/second with sub-second latency in production
• Built SSE-based real-time streaming endpoints using Axum for live trading dashboards
• Built scalable NodeJs API endpoints in Typescript using the NestJs framework
• Evaluated architectural tradeoffs between Tokio channels vs Redis Streams for event distribution, chose Redis for durability and multi-consumer support
• Designed PostgreSQL schema for OHLCV aggregation, order book snapshots, and historical trade data
• Implemented rate limiting, API key authentication, and usage tracking for monetized API access
• Had full ownership from architecture design through production deployment

An NFT collection with a game and mobile app on the Sui blockchain.

• Designed and built an NFT indexer service based on the Sui indexer alt framework for handling NFT transfers and up-to-date owner information
• Provided support and code review for Move smart contracts as well as for a Typescript NestJs backend API

The project involved integrating the Stacks blockchain with the Axelar Network to enable cross-chain token transfers.

• Designed the cross-chain transfer architecture, including Rust smart contracts on the Cosmos chain, based on the company's specification
• Designed a TypeScript NestJS relayer service for sending and processing blockchain transactions
• Architected PostgreSQL database schema for efficieny and performance, using it from a NodeJs service using Prisma framework
• Wrote Rust unit and integration tests for Amplifier service

Cross-chain interoperability solution enabling token and message transfers between blockchain networks via the company's protocol.

• Designed the cross-chain transfer architecture, including Rust smart contracts on 2 chains based on the specification
• Developed a TypeScript NestJS relayer service that sends and processes blockchain transactions
• Architected PostgreSQL database schema for efficiency and performance, using it from a NodeJs service using Prisma framework
• Wrote Rust unit and integration tests
• Handled end-to-end delivery from contract design to API integration
• Provided technical support, including architectural decisions impacting React frontend interfaces and API communication

eCommerce store selling clothes and luxury items for children.

• Migrated and upgraded 5 legacy PHP services to up to date PHP versions, improving reliability and performance
• Work across backend in PHP and frontend in React to implement new features such as new payment provider processing, product prices per country and multi language support
• Mentor junior React developers on the frontend and help with technical implementations
• Implemented an async email sending system for processing 10,000+ product update emails using queue based messaging (AWS SQS)
• Handled DevOps duties and migrated the architecture from legacy services to AWS, including setting up Terraform for managing infrastructure, migrating to Kubernetes (AWS EKS) and migrating the MySQL database with minimal downtime