Freelance Software Engineers in Purwokerto
Freelance Software Engineers in Purwokerto
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Muh. Khaerul
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Purwokerto, Indonesia
Full-Stack Dev | TS, Go & C | Reverse Engineering
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Full-Stack Dev | TS, Go & C | Reverse Engineering
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In 2024, I built Krungthai Business ExpressTS, a backend API prototype/MVP for an Upwork client working around Krungthai Business workflows. The goal was to validate how an end-to-end business banking flow could be automated while the bank does not provide official open banking APIs. My approach started with reverse engineering the mobile app flow to understand the real request/response behavior, session handling, authentication steps, and the app’s end-to-end encryption flow. This included analyzing how encrypted payloads were structured, how secure client-server communication was handled, and how the mobile client interacted with backend services during the transaction process. From there, I designed an ExpressTS-based API layer that could reproduce the core E2E flow in a cleaner backend structure, making it easier to test, automate, and integrate with external systems. The prototype focused on validating the technical flow first before moving toward a more production-ready implementation. The first approach used an OTP-based transaction flow, but I later updated the implementation toward a PIN-based flow. This made the transaction process faster and smoother for repeated usage, with the PIN flow becoming around 2–3x faster than the OTP flow because it removed the delay of waiting for OTP delivery and validation. The GitHub repository was used as a prototype/demo version for the Upwork client, focused on validating the feasibility of automating Krungthai Business workflows. Tech stack: Node.js, TypeScript, ExpressTS, Axios, Mongoose, MongoDB, dotenv, pnpm, ts-node, nodemon. If you need someone who can build backend API prototypes, reverse engineer mobile/web flows, automate complex business processes, or create integration layers when official APIs are limited or unavailable, I can help turn the flow into a clean, testable, and scalable backend system. This was an independent prototype project for client validation and research purposes, not an official Krungthai Bank product or partnership.
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Akamai Filehash Extractor Module
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HLVote: Mobile E-Voting Platform Development
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PKLSkuy — Construction Worker Marketplace Platform
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Faik Irkham
Cilacap, Indonesia
Mobile App Developer | Flutter Expert
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Mobile App Developer | Flutter Expert
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chart finance
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The main focus of this project was a clean UI/UX, smooth animations (check out those subtle transitions!), and warm branding.
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Fluty POS A Fully Offline Point of Sale System Built entirely with Flutter, this POS application is designed for small businesses that need a fast, lightweight, and reliable cashier system that works without any internet connection. Key Features: ✔️ 100% Offline – all data stored locally using SQLite ✔️ Product & category management ✔️ Fast and accurate transaction processing ✔️ Automatic inventory updates ✔️ Daily & monthly sales reports ✔️ Simple and responsive UI ✔️ Perfect for small shops, retail stores, coffee shops, and more
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FlutIoT is a Smart Home application built with Flutter, featuring a modern, responsive, and cross-platform interface for both Android and iOS. Technology Stack: - Flutter & Dart for cross-platform development - Firebase Authentication for secure login - REST API / MQTT for IoT device communication -BLoC for state management - Flutter Charts for energy analytics visualization
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