Theon Nguyen

Software Engineer

Cashion Joint Stock Company • Tiempo completo

Feb 2025 - Jul 2026 • 1 yr 5 mos

Project Portal -Built and maintained full-stack systems (Django REST + React) across manufacturing, sales, and reporting domains, integrating with third-party services (KiotViet, pawnshop system) to unify business data. -Designed and implemented a KiotViet sync pipeline (products, inventory) with automatic fallback to website APIs on public API failure, eliminating single points of failure and keeping data availability near 80%. -Integrated pawnshop APIs to synchronize core data (users, stores) into Portal, replacing manual cross-system updates with centralized, one-way configuration management. -Designed and built the Counter Shift module from scratch (DB schema, REST APIs, scheduled jobs) with automated push notifications for pre-open/close reminders and 10-minute retry cycles on overdue shifts, reducing missed shift closures. -Designed and built the Warranty module (DB schema, status-driven APIs) with real-time sync to KiotViet via Django signals, removing manual reconciliation between systems. -Developed reusable UI components and key modules (Dashboard, Manufacturing, Store, Reporting). Project Pawnshop -Refactored legacy Angular & Django codebase to a consistent architecture and coding standard, reducing onboarding time for new features. -Diagnosed slow endpoints via Django ORM SQL query logging; resolved N+1 query issues using select_related, prefetch_related, and in-memory lookup maps — cutting API response times from seconds to milliseconds and report generation from hours to minutes. -Profiled high-frequency query fields on core models and applied targeted DB indexes, further reducing latency on heavily-accessed endpoints. -Reduced frontend load times by implementing lazy loading and HTTP interceptors, scoping API calls per page/component, and parallelizing independent requests with Promise.all instead of sequential calls. -Built the asset purchase module end-to-end: valuation workflow (auto/manual pricing with approval), product finalization, purchase

Software Engineer

HDWEBSOFT Software Development Company • Tiempo completo

Feb 2024 - Feb 2025 • 1 yr

Project Booking -Developed and maintained core booking platform features using Django REST Framework — reservation management, availability scheduling, and payment integration via Stripe. -Implemented real-time chat using Django Channels, and integrated SMS and push notifications for booking-related alerts. -Diagnosed and resolved a data consistency issue between two backend services caused by a race condition — one service returned success before the other had finished persisting data. -Extended an existing TypeScript SDK with additional typed interfaces, used by other frontend teams to consume the Django backend's APIs. -Evaluated and upgraded core library dependencies to newer versions, resolving compatibility issues and reducing technical debt across the codebase. Project Human Resources Management -Extended existing Odoo HRM modules with custom business logic and computed fields to support attendance, time-off, and employee record workflows beyond standard Odoo functionality. -Customized Odoo views (XML/QWeb) and backend logic across attendance, time-off, discuss, and employee record modules to align with internal HR processes. -Designed and built a custom Odoo module from scratch to support internal HR operations not covered by standard Odoo modules, extending the platform's functional scope.