People have asked what Spire's DA Builder has to do with based rollups. It's simple: based rollups take advantage of the L1's network effect by posting to the L1 more frequently. (More often -> more powerful.) This creates a lot of frequent but small requests for blob space. DA Builder provides a simple middleware service to unify these requests from different rollups into a single complete and cost-efficient blob. This is ultimately cheaper for the based rollups, but also wastes less blob space, clearing up more capacity for other rollups!