Issue #3812 Explaination of Issuse , Request for Assign

Open Source Development
1

Subject : Proposal to add offline mode and a containerized build pipeline to App Inventor for resilient architecture and improved reliability.

I am proposing a combined feature to strengthen App Inventor’s reliability and scalability:

  • Offline Mode for the Editor – lets teachers and students keep building apps even without a constant internet connection. Projects are stored locally and sync automatically when connectivity returns.

  • Containerized Build Pipeline – modernizes the current monolithic buildserver into a microservice architecture (Docker/Kubernetes), making builds scalable, reliable, and easier to maintain.

Example Use Case:
A teacher in a classroom with unstable Wi‑Fi can still run lessons. Students build apps offline, and their work syncs when the internet comes back. At the same time, the school’s deployment can handle dozens of simultaneous builds because the containerized pipeline scales compiler services dynamically. Contributors can also run builds locally with a single docker run command, eliminating complex environment setup.

Why Current System Falls Short:

  • The editor requires continuous connectivity, so students lose progress if the connection drops.

  • The buildserver is monolithic, tightly coupled, and relies on Apache Ant/manual setup, which makes scaling and onboarding difficult.

Educational Benefit:
This proposal supports App Inventor’s mission of accessibility worldwide:

  • Accessibility: Offline mode helps students in low‑bandwidth regions.

  • Reliability: Prevents data loss and ensures smoother classroom experiences.

  • Scalability: Containerized builds support large groups of learners.

  • Sustainability: Modern architecture future‑proofs App Inventor for new platforms.

  • Contributor Experience: Simplifies onboarding and reduces technical friction.

:pushpin: Note to community: This proposal comes directly from my own experience auditing App Inventor’s architecture and identifying pain points in classrooms and contributor workflows. Assigning this issue will help us move toward a more resilient, modern, and globally accessible App Inventor.

2

Which is it, unstable wifi or unstable internet connection?

A suitably savvy IT team could build and run AppInventor locally.

3

These are separate issues. Offline syncing basically requires CRDT (e.g., what happens if the student uses multiple offline devices to edit?). This is a problem we are working on and it is a big one.

Self hosting App Inventor is not something we provide because we do not have the resources to offer customer support for it. We see that there are projects like AI2Offline provided by third parties and yet people continue to come here asking for help with it when it is not even our product. Making an official version would commit us to supporting it.

Lastly, regarding containerization: we do use it in production, but it is a non-workable solution to the development process as many of us use macOS (and some use Windows). On these platforms, docker is basically just virtualized inside of a Linux VM running on the host machine, so you pay an enormous performance penalty for every build. The performance cost outweighs the upfront investment to configure your build machine correctly.