diff --git a/README.md b/README.md
index c6cd2dc4edf..158493c6093 100644
--- a/README.md
+++ b/README.md
@@ -225,6 +225,8 @@ real-world use, add the `--release` flag to create an optimized build:
 ./mach run --release tests/html/about-mozilla.html
 ```
 
+**Note:** `mach build ` will build both `servo` and `libsimpleservo`. To make compilation a bit faster, it's possible to only compile the servo binary: `./mach build --dev -p servo`.
+
 ### Checking for build errors, without building
 
 If you’re making changes to one crate that cause build errors in another crate,