The Eagle Project
Community & Events

The community support forum registration is now open.

Please register there to keep up with the latest project developments, including some exclusive live events.

There is now an official public mirror on GitHub.

There is also an ongoing contest to escape from a hosted "Safe Eagle" sandbox instance.


Eagle (Extensible Adaptable Generalized Logic Engine) is a scripting language (and runtime library) that belongs to the Tcl family of languages.

It is interpreted, dynamically typed, and cross-platform.

It was designed to act as a "glue language" and integrate easily into existing systems written for the Common Language Runtime (CLR).

It was also designed with security in mind and there is an ongoing contest to escape from a hosted "Safe Eagle" sandbox instance.

It can also be used to write standalone applications and tools.

It is shipped (primarily) as a family of NuGet packages; however, only one digitally signed file ("Eagle.dll") needs to be distributed with applications.


The license is "Tcl-style", the exact text of which is available here.

It is a BSD style license with an additional clause that contains clarifications on its use by the Government of the United States.


Free, community-based support is available.

Please see the support page for more information.

Minimum System Requirements

The minimum system requirements are Windows XP or higher with the .NET Framework 2.0 or higher. When running on Windows, using the latest service pack of the .NET Framework on Windows 7 is recommended.

Support for running on Mono 2.0 or higher has been added. When running on Mono, using version 2.10 or higher is recommended, as several critical issues have been identified and fixed.

Support for running on .NET Core 2.0 or higher has been added.

Latest Stable Release

The beta 54 source, binary, and setup packages are now available. They have been extensively tested and should be considered "release candidate" quality. Please test them in your environment and report any issues you encounter.

For security purposes, all of the executable files available for download on this website, including the self-extracting archives, have been digitally signed by "Mistachkin Systems" (i.e. Joe Mistachkin). Please verify that the digital signatures are intact after downloading.

In addition, all RAR archive files should have valid "authenticity verification" information. Please note that the "authenticity verification" information for RAR archive files is not cryptographically secure and can be forged by a determined adversary; therefore, the self-extracting archives should be downloaded and used instead, whenever possible (i.e. on Windows).

To determine if you are running the latest build available, use the "#check" command at the interactive shell prompt. To see detailed version information, use the "#version" command at the interactive shell prompt. For more details on the latest changes, refer to the "ChangeLog" file included in the distribution.

More Downloads

Development & Source Code

There is now a publicly accessible Fossil repository for Eagle available here with mirrors available here and here.

The very latest source code is [also] always available from the trunk of the repository in the ZIP file format.

Obtaining & Using Fossil

The very latest "stable release" of the Fossil (for Windows) tool itself, as a self-contained executable file, with all compile-time features enabled, may be downloaded directly from within the Eagle repository itself.

It has been digitally signed by "Mistachkin Systems" and this should be verified via manual inspection or another trusted tool prior to making use of it.

Papers & Presentations

Eagle was presented at the 2012 Lang.NEXT Conference.

Garuda was presented at the 18th Annual Tcl/Tk Conference.

Eagle was presented at the Alt.NET 2011 Seattle Conference.

Eagle was the subject of a paper at the 17th Annual Tcl/Tk Conference, see "Tcl 2010 Conference Proceedings", ISBN 978-0-578-07483-2.

Eagle was the subject of a paper at the 16th Annual Tcl/Tk Conference, see "Tcl 2009 Conference Proceedings", ISBN 978-0-578-04533-7.

Eagle was presented at the 2009 Lang.NET Symposium.

Eagle was the subject of a paper at the 15th Annual Tcl/Tk Conference, see "Tcl 2008 Conference Proceedings", ISBN 978-0-578-00296-5.

Garuda (Eagle Package for Tcl)