Hi, I'm
Software
Developer
@ bkosinski.dev
01 / About Me
I’m a Software Developer driven by a passion for creating secure, high-performance solutions.
The part I enjoy most is building tools that help other developers — making their work faster, easier, and more enjoyable. I love finding ways to streamline workflows, create reusable components, and improve overall architecture.
Amid all of this, I always find opportunities to explore new technologies — each one feels like an adventure that fuels my curiosity and drives me to learn and understand things on a deeper level.
When I’m not coding, you’ll probably find me reading light novels, experimenting in the kitchen, or exercising.
02 / Experience
  1. Software Developer

    - Design and implementation of modular architecture in monorepo for on-premise applications.
    - Maintenance and development of existing systems, ensuring their uninterrupted functionality and compliance with business requirements.
    - Created and maintained comprehensive technical documentation for internal systems, improving onboarding and knowledge sharing across the team.
    Docker
    Laravel
    MDX
    PHPUnit
    React
    Redis
    Slim
    TypeScript
    Vitest
  2. Technical College for Computer Science

    - Laureate of Polish Technical Innovation and Invention Olympiad in category didactic help (co-creator of educational web platform Live-Text for online learning and examing).
    JavaScript
    MySQL
    PHP
03 / Projects
Websocketkit
See it on npm
Pusher
TypeScript
While implementing real-time communication between the client and server, I discovered that the provided SDK lacked proper type definitions, and calling unsubscribe in one place stopped listeners from receiving updates in other parts of the application. To address this, I created a more type-safe abstraction and only triggers unsubscribe when the final listener has been removed.
Shipment Tracking
NestJS
React
SOAP
TypeScript
When ordering packages from abroad, I often faced situations where the courier couldn’t reach me or I didn’t have enough cash on hand. I didn’t want to manually check the shipment status every day, and the official app provided only three vague statuses — with the last one always being “in transit.”

Using the public SOAP API provided by the Poland Post, I automated the entire shipment tracking process and added email notifications for status updates.
Book Collections
ClickHouse
Fastify
GraphQL
HyperDX
Kafka
Mercurius
NestJS
PostgreSQL
React
Redis
TypeScript
Frustrated by duplicate book orders and missing entries in platforms like Goodreads (especially for books in non-English languages), I am developing a personal library management system. This will allow me to track my entire collection, including multilingual titles, and efficiently manage my reading history.
04 / Contact