Job Summary: Develop and maintain web applications for large-scale data processing, inventory control, and customs reporting, with a focus on user interface and database architecture. Key Highlights: 1. Full Stack role with emphasis on React and PostgreSQL. 2. Development of complex algorithms for inventory management and prorations. 3. Ensuring transactional data integrity and data cleansing. Full Stack Software Engineer (React / PostgreSQL) Develop, optimize, and maintain internal web applications focused on large-scale data processing, inventory control (FIFO engines), and customs compliance reporting. The candidate will be responsible for both the user interface and the database architecture and logic. Essential Technical Requirements The ideal candidate must demonstrate proven proficiency in the following technologies within our ecosystem: Frontend (The Interface): Advanced expertise in React.js and JavaScript / TypeScript. Must be able to manage complex state (Context API, Hooks) and build dynamic interfaces for massive data tables. Backend & Cloud: Solid experience working with Supabase or Firebase. Must know how to implement authentication, Edge Functions (in Deno or Node.js), and consume RESTful APIs. Database (CRITICAL): Advanced proficiency in PostgreSQL. Must not only write basic queries but also master SQL function creation (RPCs), complex JOINs, aggregations, and relational database design. Data Processing: Experience handling local files. Must know how to use CSV and Excel parsing libraries (e.g., PapaParse or SheetJS) directly in the browser. 2. Key Responsibilities Design and implement complex business algorithms (e.g., FIFO inventory deduction engines, mathematical prorations, and "All-or-Nothing" validations). Ensure input data cleanliness and standardization (date parsing, removal of special characters, strict format conversion). Guarantee transactional data integrity, preventing negative balances or discrepancies in traceability tables. Securely connect the development environment to cloud production environments. Desirable Prior experience building modules for ERP systems (SAP, Oracle) or WMS (Warehouse Management Systems). Basic understanding of inventory or logistics rules (receipts, shipments, remainders, bills of materials/BOMs). Any prior exposure to international trade or customs concepts. Relentless attention to detail: In this sector, a decimal rounding error or misplaced comma in a customs document can invalidate an audit. Mathematical rigor is required. Algorithmic Thinking: Ability to translate spoken business rules (e.g., "Only use parts if the entry date precedes the exit date") into robust, unbreakable code. Assertive Communication: Ability to explain complex technical issues to continuous improvement and operations leaders. Work Location: Remote-hybrid in Reynosa, Tamps.