As part of the arXiv-NG project, we've committed to doing as much of our new development as possible in public repositories. This reflects not only arXiv's commitment to open source software and open access in general, but also the desire to facilitate collaborative work on the arXiv code base with close partners. We've decided to release all of our new code under the MIT license.
With evolvability and collaboration in mind, we're moving from a monolithic web application architecture to a more distributed service-based architecture. Giving each service (or cluster of related services) a separate code repository helps to reinforce the overall architecture, allowing the various parts of the arXiv system to evolve as independently as possible.
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