DSTS Series: Free and Open Source Tools (CURL, ExamDiff, Leaflet)

Check back every week. We will share staff picks of some of our favorite free and open source tools!


Rick Allard
Systems Engineer

CURL  is a free command-line tool for use with HTTP servers and other protocols. The lead developer won a prize for his work. It comes with macOS and Linux. You can get it for Windows, too. Here’s one simple example: the -I switch. One thing it can tell you is the Last-Modified response header. If there’s no date on a web page, this can be useful. There are many uses beyond this example.


Mary Skubic
Library Technology Support Manager

ExamDiff is a tool for visual file and directory comparison. It is simple and easy to use. There are others for different platforms, but this one is for Windows. I have been using it for years to quickly compare differences in the daily patron load files.


Bill Winston

GIS Analyst

Leaflet is an open-source JavaScript library for mobile-friendly interactive maps. Leaflet allows you build interesting maps from code that can be shared on the web.

About the author

As the Head of Data Services at Washington University in St. Louis, Moore directs services in digital data management, curation, analysis, visualization, literacies, and GIS. She was a co-PI on the IMLS grant, Community Standards for 3D Data Preservation (CS3DP), which continues to bring stakeholders together to establish agreement on how to make 3D data long-lasting (book forthcoming); a partner and curator in the Data Curation Network (DCN), which has created a shared curation model for institutions; a co-PI on the IMLS Specialized Data Curation Workshop grant, which is focused on training curators in DCN methods; and the WashU Representative for the Research Data Alliance, an international organization addressing research data. Moore is program faculty in International and Area Studies and a GIS instructor in the UCollege.