Sandal Kaigorodov

Contributed to internal and customer-facing CRM system development, with emphasis on business logic implementation, performance optimization, backend architecture design/refactoring, and new feature development. Refactored an authentication module for an internal CRM system using PHP 8.2 and Yii2, improving code maintainability and readability. Fixed RBAC role assignment logic in Yii2 for newly registered users to ensure correct access control across the system. Optimized SQL queries and ORM interactions with PostgreSQL, reducing statistics page load time by ~30x (from ~5 minutes to ~10 seconds) and eliminating report-generation delays. Developed REST APIs for wallet and payment management using Laravel, implementing core payment operations, access control, and financial data storage following SOLID, Controller-Service-Repository architecture, and Form Request validation. Implemented currency conversion and synchronous job processing to improve reliability of financial transactions and

Developed a high-performance REST API for a workout tracking system using PHP 8.2, Laravel, and Laravel Octane. Built a front-end application with Vue 3 and TypeScript, implementing user workflows and seamless integration with the REST API. Implemented passwordless authentication via Telegram Login API and integrated a Telegram bot using Nutgram to automate user interactions. Designed application architecture using Actions, DTOs, API Resources, and Form Requests to improve scalability, maintainability, and code readability. Modeled PostgreSQL schema with 12 interconnected entities and created an extensible import mechanism through a unified interface supporting Google Sheets, JSON, and external APIs—enabling new data sources without modifying core business logic. Covered core business logic with automated tests using Pest, improving reliability and maintainability. Used Docker, Docker Compose, Linux VPS, SSH, and Git for local development, deployment, maintenance, and version control

Developed and maintained university internal information systems, including the Student Portal, Moodle-based learning platform, and dormitory management system. Modernized a legacy dormitory management system by migrating from PHP 5.6 to PHP 7.2 with extensive refactoring for improved compatibility and easier long-term maintenance. Optimized complex MySQL and MS SQL reporting queries, improving execution time of resource-intensive operations by 10x. Containerized the dormitory management system using Docker on Linux to standardize deployment and maintenance. Enhanced the Student Portal using Yii2 and Laravel for 15,000+ users, implementing student registration and refactoring business logic with MySQL/MS SQL query optimizations to improve performance and stability. Integrated the Student Portal with Active Directory to enable SSO for Wi-Fi, Moodle, and other university services, reducing access-related support requests significantly. Maintained Moodle for hundreds of academic events ac