Standards & Technology

Finding aids in EmpireADC are governed by two standards: Describing Archives: A Content Standard (DACS) and the Encoded Archival Description (EAD). DACS is a United States archival description standard that provides a set of rules for describing archival and special collections. EAD is an XML markup language designed specifically for archival finding aids. It provides a set of tags defined for finding aid data elements. EAD structures finding aids and makes them machine-readable.

EmpireADC is built on two open-source software projects. Together they provide contributors with the ability to create, index, search, and display finding aids to the general public. It makes use of two cloud servers running the Linux operating system.

The first server runs Archipelago Commons digital repository software which we extended by building a web form for creating - and maintaining - finding aids for EmpireADC. Web form users enter information about a collection into the web form. The software stores the data in a JSON format and allows it to be transformed to a variety of formats, in our case EAD XML files.

The second server runs Arclight, which is software that indexes and displays EAD finding aids. The Arclight software provides the user interface for the general public to search and view finding aids in a friendly way. The Arclight server also has independent scripts that can retrieve and index finding aids hosted on other platforms, allowing us to “harvest” EAD finding aids from organizations that create them locally.

EmpireADC contributors can either use their own tools to create EAD finding aids or they can use the Archipelago web form that has been configured for finding aid creation (no knowledge of EAD required!). Finding aids created and published through the web form are automatically indexed by the Arclight software that powers EmpireADC’s public website. Locally-created EAD files can be included in EmpireADC if they are hosted on a publicly accessible web directory or uploaded to We can also harvest directly from ArchivesSpace version 2.1 or greater. Once the locally created EAD files are made accessible to EmpireADC, scripts that run on the ArcLight server will harvest those finding aids into the site and publish them to the public website.

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