Job title: Senior Full Stack Engineer
Job type: Permanent
Location: WFO, Jakarta Selatan
Job ID: 48354

Job Description

About the company

Geekhunter is hiring on behalf of our client, with a core business in consultancy and financial technology. 

Job Responsibilities

  • Taking full architectural ownership of a scalable cross-platform mobile application, with a preference for Flutter or React Native.
  • Designing clean mobile structures, including networking layers, modular systems, and state management.
  • Developing complex financial dashboards and data comparison interfaces.
  • Setting up secure mobile authentication flows, such as OTP, session management, and token refreshes.
  • Integrating REST APIs with high resilience and robust error handling.
  • Implementing secure methods for uploading sensitive identity and financial documents.
  • Building in-app purchase systems for digital products and recurring subscriptions.
  • Creating user onboarding journeys, paywalls, and subscription management flows.
  • Managing the entire release cycle and versioning while ensuring compliance with App Store and Play Store policies.
  • Tracking crash rates and proactively improving mobile performance and stability.
  • Building and maintaining secure RESTful APIs and service-layer business logic.
  • Optimizing PostgreSQL database queries and implementing Redis caching where needed.
  • Integrating the platform with third-party services like credit bureaus, payment gateways, and CRM systems.
  • Processing webhooks and ensuring idempotent validation for financial payments.
  • Setting up background jobs, scheduled processes, and detailed audit tracking systems.
  • Applying security best practices, including JWT authentication, Role-Based Access Control (RBAC), and data encryption.
  • Preventing race conditions within financial workflows to maintain data integrity.
  • Monitoring production systems to identify and resolve issues before they affect users.

Job Requirements

  • At least 5 years of total experience, with a minimum of 3 years dedicated to building production-grade B2C mobile apps.
  • Strong proficiency in Flutter or React Native, including experience shipping apps to both the Apple App Store and Google Play Store.
  • Deep knowledge of mobile state management and experience with complex API integrations.
  • Strong skills in at least one major language: Go (Golang), Node.js (TypeScript/NestJS), or Java (Spring Boot).
  • Solid fundamentals in SQL (PostgreSQL or MySQL), Redis, and background job processing.
  • Familiarity with Docker and experience deploying to cloud environments like AWS or GCP.
  • Must be proficient in both Bahasa Indonesia and English.