Siam Sarker
Building scalable backend services, asynchronous pipelines, and robust production APIs.
Based in Chemnitz, Germany. 3.5 years shipping multi-project backend systems under high delivery pressure across mining, healthcare, e-commerce, and SaaS.
About
Experience
- Architected Hykmah SSO platform using Java (Keycloak) with custom OIDC/PKCE flows and token enrichment, unifying authentication across multiple interconnected enterprise SaaS applications.
- Built a centralized user provisioning service using FastAPI and MongoDB for cross-product identity lifecycle and fine-grained access control.
- Maintained and enhanced core graduation services for Reed Events & GradPak across CakePHP and Laravel, powering commencement ticketing and registration workflows for major Australian universities.
- Engineered backend systems for Exsited/WebCommander (Grails) and Umerang (C# with GDPR compliance); conducted peer code reviews and technical mentoring across teams.
- Conducted direct technical demonstrations and architecture walkthroughs for international clients and stakeholders across Australia and Canada.
- Led backend development and system architecture for Mining Bull (later evolved into Mining Hub), engineering complex PostGIS geospatial spatial queries, spatial indexing, and high-throughput commodity tracking APIs.
- Juggled multiple client projects simultaneously under delivery pressure (Mining Hub, Nintendo Repair, Locum West), rotating between active sprint priorities and critical production releases.
- Engineered resilient asynchronous background workers (RabbitMQ, Laravel queues) and load-handling strategies to process high-volume query tasks without blocking write paths.
- Built university graduation ceremony platform with CMS template engines and asynchronous PDF certificate pipelines via RabbitMQ workers.
- Integrated third-party APIs including Autobill SDK for Nintendo warranty/repairs billing and SendGrid automation for healthcare locum staff scheduling.
- Assisted students in Structured Programming Language Lab, OOP Lab, DBMS Lab, and Computer Networks Lab.
- Helped with coding, debugging, and database queries in C, C++, Java, PHP, and MySQL.
- Guided students in network simulations and troubleshooting.
- Supported faculty with grading, lab materials, and assignments.
- Provided one-on-one mentoring to improve problem-solving skills.
Projects
Hykmah Ecosystem
A unified SSO identity platform with custom OIDC flow and token enrichment, enabling single login across multiple products.
Hykmah Ecosystem
- Tools: Java (Keycloak), FastAPI, MariaDB, MongoDB, C#, Grails
- Built unified SSO identity platform with custom OIDC flow and token enrichment using Keycloak.
- Developed centralized user provisioning service with FastAPI and MongoDB for cross-product identity lifecycle management.
- Contributed to product backends — Exsited and WebCommander (Grails), Umerang (C#).
Log Archiver
Enterprise log archival platform with columnar Parquet storage and a RabbitMQ-decoupled ingestion pipeline for high-throughput analytics.
Log Archiver
- Tools: FastAPI, DuckDB, Apache Parquet, RabbitMQ
- Columnar Parquet storage enables efficient analytics queries over large log volumes.
- RabbitMQ-decoupled ingestion sustains throughput under high load without blocking the write path.
- DuckDB used for fast in-process analytical queries over archived data.
Mining Hub Project
Developed APIs using Node.js for Mining Hub, a platform that manages mining information and locations worldwide.
Mining Hub Project
- Tools: Node.js, Express.js PostgreSQL
- Add Mining Data on different Projects under Companies.
- Build Companies and Projects Dashboard.
- Add multifunctional queries to the dashboard.
Reed Graduation
Developed a graduation service platform with a customizable CMS for universities to manage design templates.
Reed Graduation
- Tools: CakePHP, MySQL, jQuery, AJAX, RabbitMQ
- Built CMS to manage editable certificate templates.
- Applied MVC architecture using CakePHP framework.
- Integrated asynchronous processes using RabbitMQ.
- Enabled efficient graduation service customization for universities.
Nintendo Repair & Returns
Built secure APIs for admin, staff, and retailers on Nintendo Australia's repair and return service platform.
Nintendo Repair & Returns
- Tools: Laravel, PHP, REST APIs, XAMPP, Postman
- Developed role-based APIs for admin, staff, and retailers.
- Integrated Autobill SDK for streamlined invoice handling.
- Implemented secure authentication and authorization.
- Built comprehensive repair and return management system.
Mining Bull Project
Developed Laravel APIs for an Australian mining platform to manage commodities and company data efficiently.
Mining Bull Project
- Tools: Laravel, PHP, REST APIs, MySQL
- Built secure APIs for commodity and company data handling.
- Enabled efficient management of mining project records.
- Collaborated with Bit Mascot (Pvt.) Ltd. team on delivery.
- Followed REST standards and scalable code structure.
Locum West Portal
Created APIs for hospital-doctor coordination, with scheduling, auth, and SendGrid-based email integration.
Locum West Portal
- Tools: Laravel, PHP, REST APIs, MySQL, SendGrid
- Developed APIs for doctor-hospital scheduling and comms.
- Handled user creation and secure authentication.
- Integrated SendGrid for automated email workflows.
- Tested endpoints thoroughly with Postman and XAMPP.
Regional Tech Hub
Created Laravel APIs for a national initiative connecting remote Australians with digital technology support.
Regional Tech Hub
- Tools: Laravel, PHP, REST APIs, XAMPP, Postman
- Built scalable and secure APIs to support tech access.
- Improved digital engagement in rural and remote regions.
- Tested endpoints using Postman for reliability.
- Followed clean architecture and RESTful practices.
Decentralized Vehicle Info Storage System
Built a blockchain-based system to securely store and manage decentralized vehicle data using React.js and REST APIs.
Decentralized Vehicle Info Storage System
- Tools: React.js, JavaScript, HTML, CSS, REST APIs
- Implemented decentralized storage for vehicle data.
- Created a responsive UI with React.js.
- Integrated RESTful APIs for secure data transactions.
- Focused on blockchain principles for transparency and immutability.
AgroTech e-Market
Built an e-commerce platform with bidding and pre-order systems to connect farmers directly with buyers.
AgroTech e-Market
- Tools: PHP, NestJS, React Native, MySQL, TypeScript
- Implemented bidding system for fair pricing.
- Focused on eliminating middlemen to boost farmer profits.
- Project received team recognition and award.
Multi-Client Server System
Built a JavaFX-based multi-client server system using sockets for real-time communication and connection handling.
Multi-Client Server System
- Tools: Java, JavaFX, Socket Programming
- Created GUI with JavaFX for client-server interactions.
- Managed multiple client connections using sockets.
- Runnable in IntelliJ IDEA with JavaFX setup.
- Handled server-side socket communication efficiently.
Skills
Programming Languages
PHP
JavaScript
TypeScript
Python
Java
C/C++
Backend Technologies
Node.js
Express.js
Laravel
CakePHP
Nest.js
FastAPI
Socket Programming
Identity Management
Keycloak
Frontend Technologies
React
HTML5
CSS3
React Native
Materialize
JavaFX
Databases & Dev Tools
MySQL
PostgreSQL
MongoDB
DuckDB
Parquet
RabbitMQ
Docker
Git
Education
- Advanced Platforms for Automotive Systems
- Image Understanding
- Software Service Engineering
- Distributed Systems & Automotive Software Architectures
- Structured & Object-Oriented Programming
- Data Structures and Algorithms
- Database Management Systems
- Operating Systems
- Software Architecture
- Computer Security
- Machine Learning & Digital Image Processing