As part of the requirements document in DM-4155, we need a report-likely section(s) of that same document-on the currently available Wcs libraries (including, but not limited to AST Starlink and astropy.Coordinates) and summaries and references from the current literature about how other surveys and projects have managed their Wcs.

For each of the currently existing options, the report should include at a minimum:

• implementation language.
• API and languages that can interface to that API.
• how well supported (including number of contributors) is the project and how active is ongoing development.
• its performance and optimization for both scalar and vector calculations, and its scalability to large data sets.

We also need to look for and/or request technical reports and other literature from existing and completed surveys, including DES (Robert Gruendl), Pan-STARRS (Paul Price), STScI (Erik Tollerud), and SDSS (Lupton and/or Blanton?).