Back-end Engineer

Sina Heidarian

Node.js · Financial Systems · AI-assisted Engineering

Building reliable backend systems for modern financial, Web3, and product-driven platforms.

Contact Signal

sina.heydarian.sh@gmail.com Download PDF CV
Available for remote roles

Back-end Engineer focused on building reliable, scalable systems for payment, banking, and Web3 products. Experienced in designing secure APIs, transaction workflows, and production-ready backend architecture, with a strong ability to deliver practical features across complex codebases using modern AI-assisted development workflows.

Core System

Backend systems, APIs, and financial workflows

Product Domain

Payment, banking, and Web3 infrastructure

Workflow Layer

AI-assisted engineering across complex codebases

Work Experience

Back-end Developer

Felixin LLC / Webcenteriq — Remote

2022 – Present

  • Payment Workflows — Designed and implemented real-world payment processing workflows used by thousands of active users.
  • Security & Traceability — Built and maintained financial operations considering reliability, consistency, and secure data handling.
  • Provider Integrations — Integrated third-party payment providers such as Adyen and Stripe.
  • Production Reliability — Built resilient systems to handle retries, failures, refunds, and reconciliation.

Full-stack Technical Contributor

Graphgrow — Remote

Startup Engineering Contribution

  • Banking — Contributed to a modern, provider-agnostic BaaS platform.
  • Batch Payments — Designed and built batch payment functionality from scratch which handles thousands of transactions in parallel.
  • Cross-stack Delivery — Applied AI-assisted development workflows to work effectively.

Back-end Technical Contributor / Shareholder

SnoozUp — Remote

Startup Engineering Contribution

  • Data Privacy — Implemented secure handling of user health-related data.
  • Web3 Payments — Developed Web3 payment flows and wallet integrations to support thousands of blockchain-based user transactions.
  • Global Time Logic — Implemented timezone-aware logic for global users and time-based product features.

Projects

Promom

AI-related product listed in portfolio experience.

Angelink

Backend and product experience listed in portfolio projects.

Graphgrow

Banking platform focused on connecting users with banking services and supporting financial workflows such as batch payments and salary payments.

SnoozUp

Web3 wellness and fitness platform with AI-powered personalization, crypto payment flows, wallet integrations, and scalable backend services.

Quillt

Backend and product experience listed in portfolio projects.

© Sina Heidarian — Back-end Engineer