Please excuse cross postings...

Over the weekend of August 9-11, 2019, the Architect of the Capitol will shut down all power to the Library of Congress Data Center, as it has done most years in the recent past.
Systems will be down at 5pm on Friday August 9, and return to operations by 6pm Sunday August 11.

This year some of our resources will still be available:
Online access to the OPACs for the LC online catalog ( and the LC Authorities catalog ( will be served from the Library's remote computing facility and should be available throughout the weekend with data that is "static" as of Friday, August 9 at 17:00.

However,, all listservs, schemas, and stylesheets will not be accessible for that period.
The permalink service will also be unavailable.

For XML standards, we have attempted to post the schemas and stylesheets to other locations:
For METS and ALTO, BIBFRAME, the schemas and stylesheets are available on github:
Others, including MARCXML, MADS, MODS, EAD and MARC, PREMIS, VRACore are in a repository at:
For MODS and PREMIS, some stylesheets are also at:

We do encourage making local copies of all schema and xslt programs, and using catalogs, to avoid having to validate across the web.

We apologize for this inconvenience.

(We are hopeful for this to be the last time is affected by this shutdown).

Nate Trail
Network Development & MARC Standards Office
LA308, Mail Stop 4402
Library of Congress
Washington DC 20540