Karyna Siddik

Backend Software Engineer

Open to offers · Member since 21 Aug 2026

Message

Location: Italy

Desired salary: Unspecified

Work preference: Remote Only / Full Time, Freelance

Experience level: Senior

About

Professional summary

I am a backend software engineer with more than five years of experience designing and delivering scalable microservices, distributed systems, and cloud-native APIs.

I specialize in Node.js, TypeScript, JavaScript, Python, FastAPI, Express.js, AWS, GCP, Kubernetes, and SQL/NoSQL databases. My work focuses on reliable backend platforms, event-driven workflows, integrations, and production-grade API development.

I have built systems that process more than 10,000 daily orders, synchronize inventory across multiple platforms, and support marketplace, warehouse-management, payment, and subscription workflows.

I have improved API response times by 40%, reduced deployment times by 50% through zero-downtime releases, and increased platform reliability by 20% using multi-tenant architecture and scalable service design.

I am experienced in investigating complex production issues across distributed workflows, data synchronization, third-party integrations, and APIs. I trace root causes, implement corrective fixes, and contribute to refactoring and technical-debt reduction.

I also collaborate directly with clients, conduct product demos, and mentor junior engineers. I value maintainable architecture, high availability, fault tolerance, and practical solutions that improve both engineering outcomes and customer satisfaction.

Tech stack & tools

Working toolkit

Experience

Career history

Senior Software Engineer Skupreme

Jan 2021 – Jun 2026

Built and maintained production backend services for marketplace and WMS integrations, order processing, inventory synchronization, and third-party API workflows. Developed scalable microservices and a dynamic multi-tenant architecture that reduced integration time by 25% and improved platform reliability by 20%.

Optimized backend APIs to reduce response times by 40% and increase concurrent-user capacity by 25%. Implemented zero-downtime deployment architecture that cut deployment time by 50%, and built automated functions handling more than 10,000 daily orders.

Integrated marketplace, address-validation, payment, and subscription APIs. Investigated production issues across data synchronization and distributed workflows, contributed to architecture and refactoring decisions, led client demos, and mentored junior engineers.

Backend Engineer Freelancer

Jan 2021 – Jul 2021

Delivered tailored backend solutions across more than 10 projects in diverse industries, maintaining consistent five-star ratings for project deliverables.

Built and maintained backend services using JavaScript, Node.js, Express.js, MongoDB, Firebase, AWS Lambda, and EC2. Integrated third-party APIs and cloud infrastructure, including NAT gateways, to support performant and reliable application workflows.