Sebastian Dix Software

Custom Software Development & AI Solutions — Building Scalable Backend Systems

We specialize in developing high-performance backend systems, AI-powered communication platforms, and scalable microservices architectures. Our expertise in Python 3.12, FastAPI, and modern cloud technologies ensures your business gets robust, future-proof software solutions.

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Our Services

🤖 AI-Powered Platform Development

LangGraph multi-agent systems, OpenAI Azure integration, vector databases, intelligent automation, real-time communication

⚡ Senior Backend Architecture

Python 3.12, FastAPI, async systems, microservices, event-driven design, high-performance APIs

🔧 DevOps & Infrastructure

Kubernetes, Pulumi IaC, CI/CD pipelines, AWS deployment, comprehensive testing strategies

📡 Communication Systems

Multi-channel integration (email, WhatsApp, WebSocket), i18n/l10n, message routing, real-time processing

Technical Expertise

Backend & Scripting

Python 3.12, FastAPI, SQLAlchemy 2.0, asyncio, Django, Flask, Celery, Gunicorn, Uwsgi, Nginx

Databases

PostgreSQL, MSSQL, MongoDB, MySQL, Redis, SQL optimization

DevOps & Cloud

Docker, Kubernetes, Pulumi IaC, GitHub Actions, AWS (Fargate, Lambda, EC2, ECS)

Frontend & APIs

HTMX, JavaScript, CSS, HTML, REST APIs, OAuth, SSO

Linux & Tools

Bash, sed, grep, awk, Prometheus, Grafana, Selenium, pytest

Specialties

Performance tuning, reliability, distributed systems, message queues

AI/LLM Systems

LangChain, LangGraph, OpenAI Azure, vector databases, multi-agent architecture, StateGraph patterns

Communication Systems

Email processing (IMAP), WhatsApp integration, WebSocket real-time, multi-channel routing, i18n/l10n

Architecture & Testing

Microservices, dependency injection, event-driven design, pytest, Robot Framework E2E, structured logging

Our Team

Sebastian Dix

Founder & Lead Engineer — Bilingual Czech/American Senior Python Backend Developer with 4 years of experience building AI-powered communication platforms and scalable systems.

Expert in Python 3.12, FastAPI, LangGraph, and modern cloud architectures with a track record of delivering production-ready solutions.

Martin Leiblinger

Senior Software Engineer — Experienced software engineer with 13 years of expertise in delivering maintainable backend systems and scalable solutions.

Currently shaping backend solutions at ICZ a.s. in Prague, with previous experience at Accenture AI, Search Technologies, and Moravian Library. Proficient in 11 programming languages with extensive GitHub contributions.

Key Achievements

AI-powered communication platform — Built sophisticated multi-channel system handling customer interactions across email, WhatsApp, and voice messaging with real-time processing
Advanced AI agents — Implemented LangGraph StateGraph patterns with OpenAI Azure integration for automated customer service and intelligent conversation management
Scalable async architecture — Designed high-concurrency backend with Python 3.12, FastAPI, and asyncio supporting thousands of simultaneous connections
Production-ready infrastructure — Established comprehensive CI/CD with Pulumi IaC, Kubernetes deployment, and full testing suite (unit, integration, E2E)
Previous: 100x performance increase — Licensing server optimization and 90% database load reduction at Barclays

Our Approach

Reliability First — Making unreliable systems reliable with proper queue management, backpressure handling, retries, and full visibility
Performance with Intent — Turning "slow" into "fast enough" through targeted database optimization, API efficiency, query planning, and strategic caching
Production-Ready Solutions — Debugging integration failures, implementing comprehensive testing, and ensuring systems work flawlessly in production
Clear Communication — Maintaining transparent dialogue with engineers, managers, and customers throughout the development process
Modern Architecture — Leveraging microservices, event-driven design, and dependency injection for maintainable, scalable systems