diff --git a/README.md b/README.md
index 62c2f25..e48bcb5 100644
--- a/README.md
+++ b/README.md
@@ -18,6 +18,8 @@ Firstly, install MLIR (as a part of LLVM-Project):
 [same-as-file]: <> (utils/install-mlir.sh)
 ``` bash
 git clone https://github.com/llvm/llvm-project.git
+# Check out a specific branch that is known to work with ONNF.
+cd llvm-project && git checkout 476ca094c846a0b6d4d9f37710aba21a6b0b265a && cd ..
 mkdir llvm-project/build
 cd llvm-project/build
 cmake -G Ninja ../llvm \