diff --git a/Earthfile b/Earthfile
index d11c9d1b6d..9801229848 100644
--- a/Earthfile
+++ b/Earthfile
@@ -1,4 +1,4 @@
-FROM rust:1.58.0-slim-bullseye # make sure to update nixpkgs-unstable in sources.json too so that it uses the same rust version > search for cargo on unstable here: https://search.nixos.org/packages
+FROM rust:1.58.0-slim-bullseye # make sure to update rust-toolchain.toml and nixpkgs-unstable in sources.json too so that it uses the same rust version > search for cargo on unstable here: https://search.nixos.org/packages
 WORKDIR /earthbuild
 
 prep-debian:
diff --git a/rust-toolchain.toml b/rust-toolchain.toml
new file mode 100644
index 0000000000..44e678d36b
--- /dev/null
+++ b/rust-toolchain.toml
@@ -0,0 +1,2 @@
+[toolchain]
+channel = "1.58.0" # make sure to update the rust version in Earthfile as well
\ No newline at end of file