Working Location: Empire Tower (100% onsite, accessible via BTS Chong Nonsi) We are looking for a Backend Developer who wants to work on modern, high-volume, business-critical systems where backend engineering has real impact. This is not a routine CRUD role. You will work on real transaction flows, complex business logic, system integration, performance, reliability, and production-grade platforms used in large-scale operations. Our team keeps moving with modern technology. You will get exposure to modern .NET, cloud-native services, distributed systems, messaging, observability, automation, and AI-assisted development tools. Why Join Us * Work on real high-volume systems, not only internal admin tools * Build backend services that directly support business-critical operations * Learn complex transaction systems, integration patterns, reliability, and secure data handling * Use modern engineering practices, cloud services, automation, and AI-assisted development * Collaborate closely with product, business, QA, solution architects, DevOps, and external partners * Grow toward senior developer, technical lead, solution design, or domain expert roles What You Will Do * Build and maintain backend services and REST APIs * Implement complex business logic, validation, retry, routing, and status handling * Integrate with internal platforms and external service providers * Work with relational databases, query optimization, and data consistency * Support asynchronous processing using queues, events, and background jobs * Troubleshoot production issues using logs, metrics, dashboards, and monitoring tools * Improve system performance, reliability, security, and observability Requirements What We Are Looking For * Strong experience in C# / .NET / ASP.NET Core Web API * Good understanding of REST API design and backend development * Experience with relational databases such as MySQL, Aurora MySQL, or SQL Server * Strong debugging, troubleshooting, and root-cause analysis skills * Understanding of Git and standard development workflow * Ability to work with complex business logic and high-accuracy systems * Good ownership mindset and willingness to understand business context Nice to Have * Experience with fintech, payment, banking, airline, e-commerce, or high-volume systems * Experience with AWS, message queues, Redis, OpenSearch, MongoDB, or distributed logging * Knowledge of authentication, authorization, secure data handling, and production support * Experience with microservices, event-driven architecture, or third-party API integration We offer an attractive remuneration package, a fast-paced and exciting working environment, and provide challenging opportunities for life-long learning and career development. Interested candidates are invited to send your comprehensive resume with current and expected salary package via this job ad. Please note that only shortlisted candidates will be notified. Please consult our Candidate Privacy Notice to know more about how we collect, use, transfer and disclose our candidates' information: https://2c2p.com/candidate-privacy-notice. By submitting your resume and information, you understand, acknowledge, and consent that your personal data will be processed in accordance with our Candidate Privacy Notice. You consent to the collection, use, transfer and disclosure of your personal data as well as to receive email and/or other electronic messaging communication from 2C2P.