diff --git a/Cargo.toml b/Cargo.toml
index 4813ab159..cc35b1241 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -77,10 +77,21 @@ opt-level = 3
 # https://github.com/rust-lang/rust/issues/92869
 # lto = "thin"
 
-# Doesn't change often
+# Some crates don't change as much but benefit more from
+# more expensive optimization passes, so we selectively
+# decrease codegen-units in some cases.
 [profile.release.package.rustpython-doc]
 codegen-units = 1
 
+[profile.release.package.rustpython-literal]
+codegen-units = 1
+
+[profile.release.package.rustpython-common]
+codegen-units = 1
+
+[profile.release.package.rustpython-wtf8]
+codegen-units = 1
+
 [profile.bench]
 lto = "thin"
 codegen-units = 1