A project developed and presented as my degree thesis: an instant messaging web application designed with particular attention to privacy and personal data protection, with native support for end-to-end encryption. It allows users to exchange text messages, attachments and various types of multimedia content, including geographic locations, voice messages and static or animated stickers. Conversation contents are protected by AES-256-based end-to-end encryption and are accessible exclusively to the participants. Messages are also synchronized across connected clients, even in real time. The architecture consists of a client built with React and a server based on Node.js. Both are publicly distributed as Docker images. Application data, excluding attached files, is stored using Apache Cassandra.

Lala.js is an MVC framework under development, designed for building web applications with JavaScript and Node.js, partially inspired by Express. Although the project is not yet complete, the implemented features are operational and form the foundation of a structured development environment, designed to simplify the creation of robust and maintainable applications. It is the most ambitious personal project I have ever built and addresses several aspects of software engineering, from architecture design to the from-scratch implementation of fundamental HTTP request handling mechanisms, including routing and streaming body parsing. It also includes support for ranged requests and caching mechanisms, as well as integration with external systems such as databases and cache systems, with attention to maintainability, testing and documentation.

A Discord bot developed to introduce advanced server management and customization features. The project was later made open source, allowing anyone to clone the repository, customize it and deploy their own instance. Planned features include a music player, server backup and restore tools, support for custom emojis for users without Discord Nitro, member and channel counters, and additional management tools. The project also includes a React-based web GUI for server administration and settings configuration, with multilingual support for both the web interface and the bot. The architecture is based on Node.js and the Lala.js framework, with MongoDB for data persistence and Redis for caching. Deployment is designed for Linux environments via Docker containers, with the goal of making the bot publicly accessible and easy to integrate into Discord servers.

A photo-sharing social network, developed with the goal of deepening my knowledge of handling large volumes of data and designing scalable architectures. The project was presented as part of my diploma thesis, with particular focus on the system's architecture and structure. It is the first project in which I combined PHP with Apache Cassandra, a distributed NoSQL database, to explore alternative approaches to large-scale data management and persistence. The project is currently incomplete and no longer maintained, having been set aside to focus on other activities. It nevertheless remains an important learning experience in the field of distributed databases and scalable system design.

An enterprise multi-tenant microservice for configuring and sending e-mails, for which I handled most of the architecture, technical decisions and code structure, and defined the tasks and UML diagrams, coordinating the team and code reviews. It exposes server-to-server REST APIs protected by OAuth2 and supports SMTP, Microsoft Graph and AWS SES, with asynchronous sending via Apache Pulsar, priority queues, automatic retries and handling of webhooks and anomalies. It integrates multi-tenancy with Hibernate and PostgreSQL RLS, AES-256 encryption of credentials and ECDSA signing of JWTs and webhooks. It uses Elasticsearch and Amazon S3 for messages and attachments. The project includes automated tests with a minimum coverage of 90%, CI/CD, static analysis, Flyway migrations, GraalVM native compilation, Distroless Docker containers and Sentry monitoring. I also fully developed a reusable PHP/Laravel module for integration with company applications.

A shared core platform, distributed through GitLab's private Maven registry, which provides the architectural and functional foundations of the company's Java microservices. I contributed directly to its development and handled most of the architectural design, defining the code structure, components and main technical choices. I was also responsible for activity planning, defining tasks and UML diagrams, team coordination and code reviews. The platform centralizes common features such as OAuth2 authentication and authorization with Spring Security, multi-tenancy via Hibernate and PostgreSQL RLS, webhook and system notification management, credential protection with AES-256 encryption and Argon2 hashing, HTTP exception handling and Sentry integration. It also supports JWT extension through configurable Beans and the publication of public keys in JWK format via .well-known endpoints, with SQL migrations managed through Flyway. Software quality is ensured by CI/CD pipelines with automated tests, coverage measurement with JaCoCo, static analysis with PMD and SpotBugs, automatic formatting with Spotless and native compilation via GraalVM Native.