diff --git a/rust-toolchain/flake.nix b/rust-toolchain/flake.nix
index f8f1957..251a6e4 100644
--- a/rust-toolchain/flake.nix
+++ b/rust-toolchain/flake.nix
@@ -35,6 +35,11 @@
             cargo-watch
             rust-analyzer
           ];
+
+          env = {
+            # Required by rust-analyzer
+            RUST_SRC_PATH = "${pkgs.rustToolchain}/lib/rustlib/src/rust/library";
+          };
         };
       });
     };
diff --git a/rust/flake.nix b/rust/flake.nix
index a2e518e..fc9696d 100644
--- a/rust/flake.nix
+++ b/rust/flake.nix
@@ -46,6 +46,11 @@
             cargo-watch
             rust-analyzer
           ];
+
+          env = {
+            # Required by rust-analyzer
+            RUST_SRC_PATH = "${pkgs.rustToolchain}/lib/rustlib/src/rust/library";
+          };
         };
       });
     };