Live Language Demonstration / Sandbox Escape Contest

Eagle (Extensible Adaptable Generalized Logic Engine) is an implementation of the Tcl scripting language for the Common Language Runtime (CLR).

Try selecting one of the "Example Script Snippets" and then clicking the "Evaluate" button to evaluate it. Most of the important commands from Tcl 8.4 are available, including full support for namespaces.

There is an ongoing contest to escape from this "Safe Eagle" sandbox.

This demonstration uses an isolated "safe" interpreter (i.e. created with non-default options); therefore, some core language functionality (e.g. local files, network sockets, etc) is not available.

This demonstration is configured in such a way that all users, worldwide, share the same interpreter state (e.g. commands, procedures, variables, etc). This is not the recommended deployment configuration for a web application; however, for the purposes of this demonstration, it does help to stress test the library and its sandbox functionality.

Potential Shutdown in Fall 2025

Since late 2016, this free-to-use web application, which showcases the Eagle scripting language, has been running more-or-less continuously on a Windows Server virtual machine hosted partially (i.e. on host "www1") by Microsoft Azure.

Unfortunately, due to recent notifications from Microsoft regarding their phased retirement of the storage and network configurations supporting this virtual machine, it may become impossible to maintain this site.

The "solutions" as suggested by Microsoft, via their "knowledge base", will apparently require a significant investment of both time and money.

Despite multiple attempts to reach out to Microsoft for clarification or support, I have received no response.

As such, it seems highly likely that this website will no longer be available sometime in Fall 2025.

I strongly urge others to carefully consider their long-term needs before committing to any "Azure Cloud" solutions.

Thank you.

Example Script Snippets


Script Text to Evaluate (sandboxed)



Result of Script Evaluation

Project Links

LangDemo v1.0.8993.27809 (2024-08-15)