Portrait of Bastian Situmorang

Bastian Situmorang

Senior Backend Engineer · Go · Distributed Systems

Samosir, Indonesia

About

I'm a backend engineer with 7+ years of experience building and operating production systems, specializing in Go, distributed systems, and API-driven architectures.

My experience spans financial infrastructure, payment processing, banking integrations, and microservices. I work on the engineering challenges behind dependable systems, from service communication and database performance to concurrency, failure handling, observability, and production troubleshooting.

I value pragmatic engineering, clear architectural boundaries, maintainable code, and measurable performance. I aim to build backend systems that are resilient under real-world conditions, straightforward to operate, and capable of evolving with changing business needs.

Experience

  1. Systems Developer at Brankas

    Apr 2022 – Present

    • Develop and maintain payment gateway capabilities for transaction processing, including ISO 8583-based integrations.
    • Integrate payment methods across card networks, e-wallets, virtual accounts, buy now, pay later (BNPL), and QRIS.
    • Build and maintain integrations with banks, financial institutions, core banking systems, and third-party payment providers.
    • Investigate production issues and improve backend reliability through troubleshooting, monitoring, and performance optimization.
    • Contribute to Banking-as-a-Service infrastructure that connects fintech products with banking capabilities.

  2. Backend Engineer at Gokomodo

    Nov 2021 – Apr 2022

    • Helped transition inter-service communication from REST APIs to gRPC within a microservices architecture.
    • Strengthened service maintainability and regression coverage by implementing unit tests across multiple services.

  3. Software Engineer at Kurio

    Apr 2018 – Oct 2021

    • Designed and developed Go-based REST APIs for content-driven products, including a news aggregator and a recipe platform.
    • Implemented backend features for content aggregation, authentication, and category-based filtering.

  4. Software Engineer at Humbang Hasundutan Regency Government

    Jan – Dec 2017

    • Built and maintained a web-based licensing application to support license submissions, application tracking, and administrative workflows using Yii.

  5. Software Engineer at NED Studio

    Sep 2014 – Oct 2016

    • Developed mobile game features spanning gameplay mechanics, user interfaces, and performance improvements.

Projects

Skyros

A Go-based e-commerce backend demonstrating microservice architecture and inter-service communication over gRPC. Features a REST gateway, JWT authentication across service boundaries, isolated PostgreSQL databases per service, correlation-ID logging, and Docker Compose for local development.

  • Go
  • gRPC
  • PostgreSQL
  • Docker
  • Microservices
More on GitHub →

Skills

Languages
Go · SQL · PHP · Node.js
Backend & architecture
Distributed systems · Microservices · REST APIs · gRPC · Protobuf · GraphQL
Financial infrastructure
Payment gateways · Banking integrations · ISO 8583 · Payment processing
Data & reliability
PostgreSQL · Database performance · Automated testing · Observability · Production troubleshooting
Tools & infrastructure
Docker · Git · Distributed tracing · Monitoring

Education