TheiaCon 2025

Over the past year, Theia has advanced rapidly as an AI-native, vendor-neutral IDE platform and IDE, with monthly releases and a growing, vibrant community. We'll highlight the key milestones: Theia AI reaching stable in early 2025, MCP integration, major compatibility upgrades, and architectural work like the Lumino migration. We'll also put Theia's progress in context—its relationship to VS Code and its role alongside the classic Eclipse IDE as the Eclipse Foundation's next-generation tools platform. In addition, we'll answer the most frequently asked questions from users, contributors, and adopters and spotlight real-world adoption that demonstrates Theia's momentum as the open, adaptable choice for AI-ready tooling. If you want the complete picture of everything that matters in the Theia ecosystem, this is the talk you can't miss.

Collaboration in software projects shouldn't be limited to developers inside an IDE. With Eclipse Theia as the foundation and Eclipse Open Collaboration Tools (OCT) providing shared editing, we can now connect Theia-based IDEs with arbitrary web applications—making live collaboration a first-class experience for everyone involved in a project.

This talk will highlight how Theia enables real-time collaboration not only between developers, but also with project leads, stakeholders, and domain experts directly in their domain-specific tools. Key themes include:

• Why extending live sharing beyond IDEs to custom web applications changes team dynamics and accelerates feedback
• How OCT's Monaco integration enables shared editing and cross-application synchronization
• The OCT Playground as a lightweight environment to experiment with collaborative features
• Forward-looking opportunities for building truly collaborative development environments on top of Theia

Attendees will leave with a clear picture of how Theia can power collaborative development environments that bridge the gap between traditional IDE workflows and domain-specific web applications.

CrossModel is a new data modeling tool built on Eclipse Theia. It unifies textual, graphical, and form-based perspectives into a single, integrated environment that runs both on the desktop and in the cloud. By combining Langium for textual DSLs and GLSP for diagramming, CrossModel keeps all perspectives in sync through a shared logical model that serves as the single source of truth. This gives data modelers the flexibility to choose the most natural perspective for their task without fragmenting their workflow.

In this talk we will share our journey of adopting Theia, explain the architectural choices that make consistent multi-perspective editing possible, and reflect on the lessons we learned along the way. We will also show how this foundation made it straightforward to integrate AI features, such as generating data models from meeting notes and whiteboard photos, and automatically fixing models based on validation errors. A live demo will illustrate how models can be created and refined across different perspectives, with AI providing additional support. Attendees will come away with both practical insights into the design and implementation of CrossModel.

Claude Code is one of today's most powerful coding agents. It combines Anthropic's advanced language models with powerful tools for editing, globbing, and automation, but until now, it has lived primarily in the terminal. While this works for many workflows, developers increasingly expect AI coding agents to be native, interactive parts of their IDEs.

In this talk, we show how we turned Claude Code into a fully integrated IDE experience in Theia, going far beyond a simple terminal wrapper. You'll see how Claude Code becomes:

• IDE-aware with real-time context on files and projects
• Visually interactive with clickable links, actions, and visual diff editors
• Seamlessly connected through drag-and-drop context sharing and in-editor AI conversations
• ... and more, going far beyond what's possible with VS Code extensions.

Finally, for Theia adopters and tool builders, this talk goes beyond Claude Code in Theia IDE. We'll dive into details on how this integration has been developed and how Theia's open architecture enables tool builders to integrate any external AI agent into modern, customizable, and domain-specific tool environments with ease.

A great number of ISVs are still maintaining Eclipse RCP applications. Many are looking towards Eclipse Theia as a modern platform to to bring their apps into the 21st century. Find out what obstacles you are facing when porting an RCP app to Theia.

As AI-powered features rapidly become the norm in modern development environments, developers are increasingly faced with a critical question: how can we benefit from AI while keeping control over the tools we use, the models we trust, and the data we share?