diff --git a/Cargo.toml b/Cargo.toml
index f0c14aad9..4dae194c8 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -11,6 +11,10 @@ repository = "/~https://github.com/tskit-dev/tskit-rust"
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
+[profile.release]
+lto = "fat"
+codegen-units=1
+
 [dependencies]
 thiserror = "1.0"
 libc = "0.2.81"