Improve Compile Times with serde_derive
#1075
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This massively improves compile times by not forcing `serde` to depend on `serde_derive`. This allows many crates to start compiling much sooner, which ends up resulting in often quite massive compile time wins for real world projects.
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Arguably the entire derive dependency could be removed by replacing it with manual implementations, but it probably almost never would improve compile times as it would only impact how soon the url crate itself can finish compiling, but serde_derive is not on the url crate's critical path (and instead the massive idna chain is). |
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Seems like #1071 is related, as that bug is the only reason why serde (and transitively serde_derive) are even being pulled in. |
Manishearth
approved these changes
Sep 10, 2025
Codecov Report✅ All modified and coverable lines are covered by tests. Additional details and impacted files@@ Coverage Diff @@
## main #1075 +/- ##
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Coverage ? 82.54%
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Files ? 24
Lines ? 4244
Branches ? 0
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Hits ? 3503
Misses ? 741
Partials ? 0 ☔ View full report in Codecov by Sentry. 🚀 New features to boost your workflow:
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Seems like the CI error is unrelated. |
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This massively improves compile times by not forcing
serdeto depend onserde_derive. This allows many crates to start compiling much sooner, which ends up resulting in often quite massive compile time wins for real world projects.In my case this PR reduced the build times of my project (clean, release) from 91.4s to 76.0s.