Lead Software Engineer / Software Consultant

Szymon
Sadowski

At Lingaro, I build user interfaces and help shape the architecture behind them. My work spans design and implementation.

Let's talk Read the blog
01How I can help

Have a project in mind? Let's talk

  1. 01

    AI for your business

    I build AI agents and automate routine work with the latest frontier models. RAG systems give those models access to company knowledge; MCP servers connect them to the tools your team already uses. Logs, monitoring and evaluations help you track results, diagnose failures and control costs.

    • AI agents
    • MCP servers
    • RAG
    • LLM integrations
    • Frontier models
    • Workflow automation
    • LLM observability and logs
    • AI evals
  2. 02

    Web apps and platforms

    I design and build web applications, SaaS platforms, dashboards and internal tools. The work covers the interface, system architecture and APIs, through to deployment and monitoring. Next.js, React and TypeScript are the core of my web stack.

    • Next.js
    • React
    • TypeScript
    • SaaS
    • Dashboards
    • Internal tools
    • UI/UX design
    • System architecture
    • Logging and monitoring
  3. 03

    Mobile apps

    I build applications for iOS and Android, from the first designs to release on the App Store and Google Play. I also develop progressive web apps (PWAs), which users can add to their home screen without visiting an app store.

    • iOS
    • Android
    • Swift
    • React Native
    • Expo
    • PWA
    • Push notifications
02My apps

myDonner

A single place to keep your dog's health records, medication history and vet appointments. Records can be exported, and appointments are managed in Google Calendar. Built with Next.js, Convex and Clerk, it also works as a PWA on your phone.

my-doner.vercel.app 

Tennis AI Coach

An app that analyses tennis recordings and offers AI feedback, with a particular focus on the serve. You use your own API key; signing in lets you save recordings and their analysis. Built with Next.js, Convex and the Vercel AI SDK.

tennis.szymonjakubsadowski.com 
03Blog

More on software and AI: all articles

04Templates

Code you can use as a starting point for your own projects.

nextjs-google-calendar-template

A Next.js template for integrating Google Calendar. Its google-calendar.ts module handles calls to the API, so you can build on an existing integration.

GitHub repo 
05Elsewhere

You can find me on X and LinkedIn. My code is on GitHub.

06Work with me

Let's talk

Tell me what you want to build or what needs to work better. A short description is enough to start a conversation about AI, a web platform or a mobile app.