Resolver One is a Spreadsheet program created by Resolver Systems with the IronPython programming language. It is a desktop application, with a web server version, and intended as a platform for the rapid development of business applications. It runs on Microsoft Windows, and is free for use in Open Source projects. .
Resolver One combines the functionality of a spreadsheet and an IDE. Spreadsheets are turned into Python code and executed in real-time. Code can be mixed, using both Python and .NET libraries. Spreadsheets can also be exported as stand alone programs.
On 3 October 2012, Resolver Systems announced that the product had reached its end of life, and would no longer be developed, due to insufficient sales.