Alex K.

Most backend issues in production systems are not caused by technology - they come from early architecture decisions, fragile integrations, or systems that were never designed to scale. I help startups and product teams design and build reliable backend systems that hold up in production, not just prototypes that work in demos. Over the past 4+ years, I’ve worked on backend systems powering real products - designing APIs, data architectures, and event-driven systems using Node.js and Go. 𝙋𝙧𝙤𝙫𝙚𝙣 𝙩𝙧𝙖𝙘𝙠 𝙧𝙚𝙘𝙤𝙧𝙙 ・1200+ hours on Upwork delivering high-end development services ・100% Job Success Score (JSS) ・4+ Years in Software Engineering with a deep focus on Node.js & Go 𝙒𝙝𝙖𝙩 𝙄 𝙘𝙖𝙣 𝙝𝙚𝙡𝙥 𝙮𝙤𝙪 𝙗𝙪𝙞𝙡𝙙 Backend & API Development ・REST, GraphQL, and tRPC APIs ・Node.js frameworks: Express, Fastify, NestJS ・Clean API contracts and versioning ・Third-party API Database & Data Architecture ・PostgreSQL, MongoDB, ClickHouse ・Schema design and migrations ・Query optimization ・ORMs: TypeORM, Drizzle, Sequelize, Mongoose Event-Driven & Real-Time Systems ・Message queues with NATS and BullMQ ・Real-time communication via WebSockets or SocketIO ・Event-driven architectures for scalable services Data Acquisition & Automation ・API reverse engineering ・Web scraping systems ・Automation using Puppeteer and Playwright 𝙇𝙚𝙩’𝙨 𝙩𝙖𝙡𝙠 If you're building a system that needs to scale, remain maintainable, and survive production growth, I’d be happy to discuss your project. 𝘾𝙤𝙧𝙚 𝙏𝙚𝙘𝙝𝙣𝙤𝙡𝙤𝙜𝙞𝙚𝙨 Node.js • TypeScript • Go Express • Fastify • NestJS PostgreSQL • MongoDB • ClickHouse NATS • BullMQ • WebSockets • SocketIO TypeORM • Drizzle • Sequelize • Mongoose Puppeteer • Playwright