Vasilis Spilka on LLMs & Ash

About this episode

Vasilis Spilka discusses building agentic software, the integration of Ash and LLMs, and the journey of developing a startup alongside a day job.

In this episode of the Elixir Mentor Podcast, I chat with Vasilis Spilka, Head of Software Development at Teacherspace, about building agentic software as a solo developer, the pairing of Ash and LLMs, and what it takes to ship a startup side project alongside a day job. Vasilis shares his path from Ruby on Rails in 2014 to nearly a decade of Elixir work across fintech, supply chain, and ad tech. We talk through Teacherspace's recent acquisition, the challenges of integrating with legacy Danish education contractors, and the three pivots it took to land on a working product. We spend a good chunk of the episode on Ash: why its unique DSL and introspection make it unusually strong with LLMs, how Spark lets you build your own DSLs, and why usage rules plus Igniter are a game-changer for library authors. Vasilis walks through his Claude Code workflow, the sculpting approach he uses for prototypes, and where he still won't let the LLM near — system design and API keys. The conversation also covers Communities, his local-first social platform; the paperclip-style autonomous company idea he's exploring with ash_typescript; whether LLMs actually understand anything; and the unglamorous…

People in this episode

Host: Jacob Luetzow

Guest: Vasilis Spilka

Topics covered

• agentic software
• LLMs
• startup development
• software development
• Elixir
• product integration
• prompt engineering

Keywords

• software development
• Ash Framework
• LLMs
• Elixir
• startup
• prompt engineering
• Claude Code
• Tidewave
• Igniter

Mentioned in this episode

Organizations: Teacherspace, Ash, Ruby on Rails, Elixir, fintech, supply chain, ad tech, Claude Code, Communities, ash_typescript

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