About Me - Technical Achievements

companies I`ve worked

The Story

As a child, I was always fascinated by computers. At the age of 20, I decided to pursue a career as a professional software developer. I began taking C++ courses and passed the Plovdiv University (PU) entrance exam with a score of 5.40. However, shortly after that, I moved to Sofia and started working at a company called Freido, where I initially worked with PHP.

Later, I joined StangaOne, where we actively used the Symfony Framework, along with Doctrine & Propel ORM, for backend development. Of course, we also worked with HTML, CSS, and JavaScript. In addition, we integrated various payment methods and implemented numerous other features.

During my 20 years of experience, I have worked for various companies both as a full-time employee and a part-time contractor. Throughout my career, I have developed my skills and gained a deeper understanding of the industry.

I have collaborated with various Bulgarian companies, such as:

Tech Reserve

BMS - Bulgarian kitchen

Aдвокат Росен Димитров

SoftUni

and many others

As well as international ones, such as:

At StangaOne I have worked on various and complex applications in fields like banking system, e-commerce and etc. We integrated:

🔥 different payment methods and API's
🔥 unique and attractive UI's
🔥 complex server-side & frontend logic

Later on — about a year ago or some time back — they contacted me again, and we collaborated on a project for a large German corporation. The application was relatively large, with many internal services and a lot of legacy code.
It included features such as and .
As a senior developer, I was part of a team responsible for developing a split-payment service. For example, when you're at checkout and want to pay for your products, the system allows you to pay part of the amount in cash and the rest with a debit card. In the end, the total is calculated, and the bill is settled.
Some of the technologies we used included Vue 2/3VueJS is a lightweight, open-source JavaScript framework for building user interfaces and single-page applications (SPAs). It’s known for being simple to learn, flexible, and developer-friendly.
Vue uses a declarative and component-based architecture, similar to React, and allows you to build reusable UI components. It also supports reactive data binding, making it easy to keep your UI in sync with the underlying state.
Vue is a great choice for both small projects and large-scale applications, and it's often praised for its clear documentation and gentle learning curve. , FastifyFastify is a fast and lightweight web framework for Node.js designed for building high-performance APIs. It offers a minimal and efficient core with powerful features like schema-based validation, built-in support for plugins, and optimized HTTP handling. Fastify is ideal for both small services and large-scale applications where speed and low overhead matter. , KafkaWhat is Kafka?
Apache Kafka is a high-performance, distributed platform used for building real-time data pipelines and streaming applications. It allows systems to publish, subscribe to, store, and process streams of records (messages) in a fault-tolerant and scalable way.
Kafka is commonly used in event-driven architectures (EDA), where different services communicate through events rather than direct API calls. For example, when a user places an order, an event is sent to Kafka, and multiple services (billing, shipping, notifications) can react to that event independently.
It’s widely adopted in industries that require real-time processing, like finance, e-commerce, and IoT.

, PostgreSQLWhat is PostgreSQL? PostgreSQL is a powerful, open-source relational database management system (RDBMS) known for its reliability, scalability, and advanced features. It uses SQL (Structured Query Language) for defining and querying data and supports ACID compliance, ensuring data integrity and consistency.
PostgreSQL goes beyond basic SQL with support for:
JSON & full-text search (great for modern apps).
Custom data types and functions.
Extensibility via plugins and extensions like PostGIS (for geospatial data).
It’s widely used in production systems — from startups to large enterprises — and is ideal for apps that need complex queries, strict data integrity, or high performance. , TypeORMWhat is TypeORM? TypeORM is an Object-Relational Mapper (ORM) for TypeScript and JavaScript, used to interact with relational databases like PostgreSQL, MySQL, SQLite, and others. It allows you to work with database tables as TypeScript classes and objects, making database code cleaner and easier to maintain.
Key Features:
Define tables using TypeScript classes and decorators (@Entity, @Column, etc.).
Supports migrations, relationships (one-to-many, many-to-many), and lazy loading.
Works well with modern frameworks like NestJS, Express, and Fastify.
Integrates smoothly with PostgreSQL, MySQL, MariaDB, SQLite, and more. , and others.

One of the most interesting projects I have worked on is Diversity.com — a job posting portal for minorities in the United States.

After presenting several ideas and developing the first version of the website, the client was highly impressed with my work and style and promoted me to the role of Technical Manager. They handled the sales aspect, while I was responsible for the technical side of the business, including website development, tools, team, and online marketing.

To support the project's growth, we needed to expand the team by hiring additional programmers, designers, and marketers. Once we assembled the team, the business took off significantly, generating a monthly profit of approximately $100,000.

A large part of this success was due to my ! One of the biggest achievements was getting the website indexed as the #1 result on Google for the keyword "diversity" — a remarkable milestone, considering how extremely competitive the U.S. market is for top-ranking keywords on Google. This happened around 2017.

I learned how to create websites that appear on the first page and even in the first position on Google.

Responsibilities:

🔥 Developing complex applications, integration of third party API's, payment methods
🔥 Managing marketing strategy
🔥 Managing team of 4 specialists
🔥 Communication with stake holders, planning, goal achieving strategy
🔥 High Level Sytem Design and Architectures

Some of the technologies we used included: , ,, , HTML, CSS, .

Interesting case:

While we were developing this application, there were many additional projects and technical challenges that I had to solve.

One particular case study involved a database with several million records (100M+ records) and daily traffic of 50,000 – 70,000 visits on the homepage. The challenge was to implement a slider that retrieves results from the database via AJAX and displays them on the homepage, all while ensuring a load time of under 1 second (based on requirements).

Simply optimizing the database query was not enough — a non-standard solution was required!

I came up with an effective approach: I created a cron job that selects 250 job posts from millions of records. This cron job runs every six hours and stores these 250 job posts in a JSON file. The slider then randomly selects 60 records from this pre-generated JSON file, ensuring fast page load times.

References

After Diversity.com, I started activly working with NODEJS (ExpressJS), REACT (Nextjs), TYPESCRIPT and maintly JS technologies. My main tech stack at the moment.

I was also approached by individuals from minority communities in Bulgaria who were consistently facing issues with approval and account restrictions. Due to automated moderation systems often flagging their content unfairly, they sought my support in running their campaigns. I provided strategic guidance and technical support to help them navigate policies, including optimizing ad creatives(at one point, we managed to optimize one of the campaigns to cost just $0.001 per click — one of the lowest CPCs we’ve ever achieved), managing compliant ad accounts, and, where necessary, using legitimate workarounds to ensure their voices could be heard. This experience reflects my ability to find ethical, practical solutions in challenging digital environments and demonstrates my commitment to supporting underrepresented communities online.

Another interesting project I worked on was for InfiniGods.com, a gaming platform where users can play, earn , and trade them. The project was originally outsourced to an external agency, but their implementation was poorly done — it used a hybrid setup: PHP for the backend and an outdated version of React (v16) for the frontend. As expected, this caused multiple issues, especially since PHP didn’t support web3 features natively, while JavaScript had already matured with tools and libraries like ethers.js.

As a senior developer, my responsibility was to take over the entire project from the external team, set up and manage a new Linux-based VPS server, and rebuild the application from scratch using (withTypeScript) and ExpressJS for the backend. This new architecture allowed us to implement essential business features properly, including , Ethereum smart contract communication, and other blockchain-related functionality.

It was also the first time I learned how to interact with written in other languages (e.g., ) directly from JavaScript code, which was a powerful and exciting experience. I gained solid hands-on knowledge of web3, especially around wallet integration, blockchain interaction, and decentralized application (dApp) infrastructure.

This project greatly expanded my expertise in both modern full-stack development and the web3 ecosystem, and I’m truly grateful for the opportunity to work on such cutting-edge technology.
Checkout my simple personal demo with web3 project

I worked with We Craft Media on a project where we had to build a React & TypeScript interface for managing electric vehicles for one of their clients. The backend was built with ExpressJS. As a senior developer, I was responsible for the frontend, and one of the ideas I proposed at the time was to use , as it was quite advanced for its time and worked very well with the principle of , among other things. This significantly improved the app's productivity. The application itself was complex, as managing electric vehicles involved many features, options, and various scenarios that needed to be integrated.

References

I also led the development of a highly complex full-stack banking application, initially as the sole engineer and later as team lead. The project required integration with third-party APIs such as and to conduct sanctions and compliance checks on users across 150+ countries. I was responsible for designing a scalable database architecture, implementing the core backend logic for handling international transactions, and ensuring full compliance with the unique regulations and financial requirements of each jurisdiction.

In addition to the backend, I also built an intuitive frontend interface using NEXTJS NextJS NextJS is a full-stack React framework for building web applications with features like server-side rendering (SSR), static site generation (SSG), and API routes out of the box. It optimizes performance, SEO, and developer experience by handling routing, code splitting, and image optimization automatically. With support for both client and server logic, NextJS is ideal for modern web apps — from content-rich sites to complex dashboards. , allowing users to view, search, and filter their transactions with all the necessary details. As the team grew, I took on the responsibility of mentoring new developers, managing task distribution, and maintaining high technical standards across the codebase.

At ZebrineX we did a prototype project with React, firebaseDB and ExpressJS.

We had a project where we needed to integrate AI. The idea was to allow the client(IKEA, etc.) to upload various large files (with milions and milions of records - 50M+ records) into the system, from which we would read the content, vectorize it, and store it in a vector database. Then, when the client performed a search, we would return results not just based on keywords but also based on semantic meaning.

As a team lead, I was responsible for the overall architecture of the project, the technical decisions and the implementation of the project. Training and mentoring of the team also was part of my responsibilities.
Then, we would use Python (, , etc.) and its libraries to perform cleaning & structuring of the datasets, vectorization and store the data in the vector database. We build our own models for vectorization and clustering of the data.
As for NodeJS — which we used as the base of the system — the overall architecture was a hybrid application, where each programming language was used for the task it excels at. This idea of using the best-suited language for each operation was key to achieving high performance.

References

At NG Coding / Build Co Lab — a cloud-based software platform for managing construction processes and companies — we were developing a centralized hub that enables construction firms to create schedules, assign tasks, manage contracts, and track progress, budgets, and communication in real time, all enhanced by integrated artificial intelligence.

Initially, we utilized and pg-vector, but as the platform evolved, we enhanced our technology stack by transitioning to dedicated vector databases and adopting more specialized embeddings, as well as integrating and to improve AI-driven capabilities.

As a team lead, my responsibilities included assisting and advising on the database architecture to optimize it for high performance.
Database optimization was a key factor in improving the overall performance of the application. This involved integrating additional vector databases, among other enhancements.

I also supported efforts to improve the codebase structure and the performance of the server-side business logic by recommending a migration to Fastify Fastify Fastify is a fast and lightweight web framework for Node.js designed for building high-performance APIs. It offers a minimal and efficient core with powerful features like schema-based validation, built-in support for plugins, and optimized HTTP handling. Fastify is ideal for both small services and large-scale applications where speed and low overhead matter. , due to its higher performance characteristics. Additionally, I introduced and enforced several best practices to ensure the code was better structured and more readable — which we successfully implemented.

We had to integrate complex construction-related formulas and workflows, both on the server and the frontend, which we implemented to enable advanced analytics.

Later, I was actively involved in the development of the frontend, where we used the latest versions of and . We integrated global state management in both the client and server components — and based on our research, was the only solution offering this level of flexibility at the time. In addition, I played a key role in integrating AI features using and , including the development of agents and working with .

Throughout the process, I frequently mentored and supported mid-level and senior engineers.

References

The next project I worked on was for a client of Tech Reserve who wanted to develop agents capable of opening and closing trades on the stock market.

Initially, the client proposed creating five separate agents, each making decisions based on data we scraped from a third-party professional portfolio. This would have resulted in five independent, autonomous projects. I optimized the architecture by implementing , and where I designed a single agent equipped with tools that could be invoked in different situations. Depending on the context and need, the agent would dynamically call the appropriate tool.

This approach significantly improved and streamlined the application's architecture, reduced development time, and enhanced code quality by adhering to clean and DRY principles. The client was extremely impressed and pleased with the outcome.

The technologies we used included , MCP, and vector databases.

Next Project: Advancing AI Education through LangChain & Agent Architectures

Soft Uni — Software University - SoftUni

As part of my ongoing mission to bridge practical AI with real-world application, my next project involves to design and deliver an . Building on a successful guest session where I demonstrated reasoning pipelines and tool integrations, this initiative aims to empower developers with hands-on knowledge, foster a vibrant AI community, and share cutting-edge techniques for building intelligent agents.