Julia set z ↦ z² + c

A Julia set: the boundary between points that escape to infinity and points that stay bounded under repeated iteration of z ↦ z² + c. Each value of c paints a different shape; this one drifts slowly.

Piotr Tobiasz

tobiwan, senior software engineer, Poland

I'm Piotr, a software engineer from Poland. I've been working remotely for around seven years, mostly on the backend, focusing on scalable systems.

Started with Java and Minecraft mods, moved to Python and web in college. I've experimented with many technologies, and eventually settled on Go and Elixir. I love Go for its simplicity and Elixir for its declarative nature, OTP completeness, and the joy of expressing complex systems beautifully.

I love engineering for its endless possibilities, exploring the aesthetics of software, and applying pragmatic craftsmanship. For me, building cohesive software is expressing my creativity.

I also write on Substack. Haven't been too consistent with it, planning to improve.

Off-hours: nonfiction, history, fantasy books; gaming; kickboxing; fighting back pain.

Highlights

Experience

  1. Appunite 11.2025 – present
    Software Engineer
    • Economic and financial data platform.
    • Worked on multi-tenant SaaS for economic data access, built on an Elixir/Phoenix umbrella of 20+ apps, PostgreSQL, Oban.
    • Built and maintained the library system for tree-structured content management, with granular permissions and versioning.
    • Built a graph rendering pipeline: Elixir backend → Node.js renderer → Apache ECharts → SVG/raster output.
    • Authored ADRs restructuring monolithic components into focused, independently testable umbrellas.
  2. DubClub 06.2024 – 11.2025
    Senior Software Engineer
    • Scalable system for managing sports content creation businesses.
    • Worked on Stripe payments and subscription management, used by hundreds of thousands of subscribers.
    • Migrated content publishing from Celery to Go, cutting delivery from minutes to seconds.
    • Built Temporal workflows replacing problematic Celery tasks.
    • Redesigned auth from SMS to email OTP and social logins, cutting cost while improving security and UX.
    • Designed and built multi-user business architecture with role-based access control, replacing single-user ownership.
    • Redesigned automated campaigns, lifting conversion from ~2% to ~8–14%.
  3. Scoutbee 10.2022 – 06.2024
    Backend Engineer
    • AI-powered supplier discovery platform.
    • Worked on customizable supplier search via ElasticSearch and GraphQL, built with FastAPI, SQLAlchemy, PostgreSQL.
    • Led development of an AI chatbot for supplier discovery.
    • Main contributor to SAP-certified Scoutbee Discovery (opens in new tab), listed on the SAP Store.
    • Established observability and monitoring using structlog, Datadog, Sentry.
    • Ran technical interviews and led implementation teams.
  4. STX Next 12.2020 – 10.2022
    Python Engineer
    • Procurement and supply chain web apps.
    • Developed and maintained monolithic applications in Python and Django, with PostgreSQL, Redis, Celery, RabbitMQ.
    • Improved performance and scalability of distributed systems.
    • Designed and implemented microservices using FastAPI.
    • Built Auth0-based authentication, authorization, and user management.
    • Collaborated in small agile teams and large cross-functional groups.
  5. Nokia 11.2019 – 12.2020
    Junior Python Developer
    • Internal tools for employee and team management.
    • Developed and maintained monolithic applications in Django and Angular, with PostgreSQL, Redis, Celery, RabbitMQ.
    • Worked in a small agile team.

Education

Skills

Contact

Reach me on LinkedIn (opens in new tab), GitHub (opens in new tab), or Substack (opens in new tab).