Robert Hensing
b13fc7101f
Source filtering is a really cool Nix feature that lets us avoid a lot of rebuilds, which speeds up the iteration cycle a lot in cases where the relevant source files aren't actually modified. We used to have a source filter that marked a few files as irrelevant, but this is the wrong approach, as we have many more files that are irrelevant. We may call this negative filtering. This commit switches the source filtering to positive filtering, which is a lot more robust. Instead of marking which files we don't need we marked the files that we do need. It's a superior approach because it is fail safe. Instead of allowing build performance problems to creep in over time, we require that all source inputs are declared. I shouldn't have to explain that declaring inputs is a good practice, so I'll stop over-explaining here. I do have to acknowledge that this will cause a build failure when the filter is incomplete. This is *good*, because it's the only realistic way we could be reminded of these problems. These events will be infrequent, so the small cost of extending the filter is worth it, compared to the hidden cost of longer dev cycles for things like tests, docker image, etc, etc. (Also rebuilding Nix for stupid unnecessary reasons makes my blood boil)
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