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Products we built, grew, and run as founders

We don't just write code for clients. We run our own businesses — finding users, shaping the business model, making hard product decisions, and staying accountable for growth every day. When we work on your product, we bring that same founder perspective.

Work with product founders →
Active Business — Founded & Run by Us

Guntracker.pl

guntracker.pl →

We identified an underserved niche — sport shooters in Poland had no single place to compare stock and prices across retailers. We built the marketplace, designed async-capable data pipelines that aggregate offers from dozens of shops, and integrated third-party APIs for payments (Stripe) and logistics (InPost). Every product decision is ours: what to track, how to present prices, when to add new features. We proved product-market fit with real users and real retention — and we continue to grow it.

This isn't a side project or a client build. It's our active business — we handle user acquisition, community engagement, retailer relationships, and the full technical stack every day. The platform is delivered as a PWA with real-time communication via WebSockets, queue-based background processing, and an API-first architecture that supports both the marketplace and the booking system.

B2C user acquisition Community building Marketplace dynamics Product-market fit Data pipelines SEO & organic growth
Backend Elixir Phoenix PostgreSQL Oban
Frontend Next.js React PWA
Infrastructure Docker CI/CD
Integrations Stripe Payments InPost Shipping Web Scraping APIs
Patterns API-first architecture Queue-based job processing Real-time WebSockets Background data pipelines
50+
retailers tracked
1000s
offers aggregated daily
Active
community across Poland
PMF
validated with real users

What we own

  • Product vision and roadmap
  • User acquisition strategy
  • Full technical architecture
  • Data scraping and categorization
  • Community management
  • Business model and monetization
Active Business — Founded & Run by Us

Towar.ai

towar.ai →

Organizations struggle to move beyond chatbots into real AI automation. We're building Towar — a multi-tenant platform with strict tenant isolation where AI agents don't just answer questions, they operate autonomously: on schedules, in response to events, collaborating in teams, learning from every interaction. The platform integrates multiple LLM providers through prompt orchestration, with OAuth2/JWT authentication and role-based access control (RBAC) governing every interaction.

This is our most ambitious business — an actively growing B2B SaaS platform that we operate, sell, and evolve every day. We engineered the full agent execution loop including memory, tool calling, capability management, and inter-agent communication. The system supports spawning multiple concurrent agents coordinated in real time, leveraging Elixir's BEAM concurrency model and event-driven architecture for reliability at scale.

B2B SaaS strategy Platform business model Go-to-market Pricing model design Multi-tenant architecture AI/LLM infrastructure
Backend Elixir Phoenix LiveView PostgreSQL Oban
Frontend Phoenix LiveView REST API Messages API
Infrastructure Docker BEAM OTP Supervisors
Integrations OpenAI API Anthropic API MCP Protocol OAuth2 / JWT
Patterns Multi-tenant architecture Tenant isolation RBAC AI/API integration Prompt orchestration Event-driven architecture Concurrent agent execution
See Towar capabilities →
483K
lines of production code
349
PRs merged
2.5mo
from zero to production
7B
tokens processed

What we own

  • Product vision and architecture
  • Business model and pricing
  • Go-to-market and sales
  • Full platform engineering
  • AI agent framework design
  • Multi-tenant infrastructure

What building our own products taught us

Every lesson here was learned with our own money, our own users, and our own reputation on the line. That's the perspective we bring to your product.

User acquisition isn't someone else's job

When you build your own product, you learn that the best code means nothing without users. We've done SEO, community building, content marketing, and direct outreach for our own products. We bring that growth mindset to every project.

Product decisions have consequences

Every feature we built or didn't build affected our users and our business. We bring that same discipline to your product — build what matters, skip what doesn't, and make every decision count.

Revenue changes how you think about architecture

When it's your money, you learn to build systems that are reliable, cost-efficient, and maintainable. No gold-plating, no premature optimization, no unnecessary complexity. Just what works.

Products we helped build

Before founding our own products, we spent 13+ years building at scale for other companies. These are some of the products we contributed to.

Full-Stack Engineers — 10-Person Team

Fishbrain

Team of 10 · 3-month delivery · 13M+ users

Complete e-commerce frontend rebuild and backend performance improvements for the world's largest social network for anglers. We led a 10-person cross-functional team, rebuilt the React.js web frontend from scratch, contributed to native mobile features, and optimized the Ruby on Rails backend with Elixir components — delivering a production relaunch in just 3 months while serving 13M+ active users through an API-first product architecture.

Backend Ruby on Rails Elixir PostgreSQL
Frontend React.js Native Mobile (iOS/Android)
Patterns Scalable cloud infrastructure API-first product Async-capable background jobs

Key contributions

  • Complete e-commerce frontend rebuild in React.js
  • Backend performance optimization for millions of DAU
  • Native mobile feature development
  • Production relaunch in 3 months
Lead Backend Engineer — Zero-to-One Build

Finley

Fintech · Zero to first users · Elixir

Zero-to-one fintech product built from concept to first users. We designed and built the entire Elixir backend — integrating bank APIs and Banking-as-a-Service providers for real-time virtual card issuance, implementing PCI-compliant data handling, and building event-driven pipelines with WebSockets for live transaction updates. Deployed on scalable cloud infrastructure with Google Cloud and Kubernetes for production-grade reliability.

Backend Elixir Phoenix PostgreSQL Oban
Infrastructure Google Cloud Kubernetes Docker
Integrations Bank APIs BaaS Providers PCI-compliant data handling
Patterns Event-driven architecture Queue-based job processing Real-time WebSockets Scalable cloud infrastructure Advanced reporting pipelines

Key contributions

  • Bank API and BaaS integration for virtual card issuance
  • PCI-compliant data handling architecture
  • Event-driven real-time transaction updates via WebSockets
  • Google Cloud + Kubernetes production infrastructure
  • Advanced reporting and data pipeline design
Full-Stack Engineers — iOS, Android & Backend

Solo Vendor

Live events · Real-time ordering · Cross-platform

Live food ordering application for stadiums and events. We built the complete stack — native iOS and Android apps for attendees, a Ruby on Rails API backend handling real-time order processing, and venue management tools for operators. The system managed concurrent ordering spikes during live events with queue-based job processing via Redis and real-time status updates through an API-first architecture.

Backend Ruby on Rails PostgreSQL Redis
Frontend iOS (Swift) Android (Kotlin)
Patterns API-first product Queue-based job processing Real-time order tracking

Key contributions

  • Native iOS and Android ordering applications
  • Real-time order processing backend
  • Venue and operator management system
  • Concurrent spike handling for live events
iOS Engineer — Streaming Platform

Zumba Fitness — ZIN Play

Global fitness brand · Streaming · iOS

Streaming platform for Zumba instructors used by a global community. We built the iOS application delivering on-demand and live video streaming, content management, and a polished mobile experience for one of the world's most recognized fitness brands. Integrated with third-party streaming APIs and OAuth2 authentication for secure content access control.

Frontend iOS (Swift) AVFoundation
Integrations Third-party streaming APIs OAuth2 authentication
Patterns Async-capable media streaming API-first consumption

Key contributions

  • Native iOS streaming application
  • On-demand and live video playback integration
  • Authentication and content access control
  • Polished UX for global fitness community
Full-Stack Engineer & Team Lead — Team of 8

Tahmeel

Logistics · Fleet management · Elixir + Vue.js + iOS

Logistics and fleet monitoring platform serving the B2B delivery market. We led a cross-functional team of 8 building an Elixir backend, Vue.js web dashboard, and native iOS app. The system handles complex routing algorithms, real-time fleet tracking, and booking management for enterprise logistics operations — with role-based access control (RBAC) separating fleet operators, dispatchers, and administrators across a multi-tenant application architecture.

Backend Elixir Phoenix PostgreSQL
Frontend Vue.js iOS (Swift)
Infrastructure Docker containerization
Patterns RBAC Multi-tenant application Real-time fleet tracking API-first architecture

Key contributions

  • Elixir backend for routing and fleet management
  • Vue.js operator dashboard with role-based access
  • Native iOS driver and booking application
  • Real-time fleet tracking and monitoring
  • Team leadership across 8-person cross-functional team

Want founders building your product, not just developers?

We bring the same product thinking, growth mindset, and technical judgment to your startup. Let's talk about what you're building.