diff --git a/flake.nix b/flake.nix
index 94806a8..c0ebf50 100644
--- a/flake.nix
+++ b/flake.nix
@@ -10,6 +10,14 @@
       in
       {
         devShells.default = pkgs.mkShell {
+          # Disable all Nix hardening flags to prevent interference with Cargo builds.
+          # These flags are designed for C/C++ and can cause issues with:
+          # - MUSL builds (fortify adds glibc-specific functions)
+          # - Crates that vendor C libraries (e.g., git2 vendoring libgit2)
+          # Rust already provides memory safety, so these hardening flags provide
+          # minimal benefit while causing build problems.
+          hardeningDisable = [ "all" ];
+
           buildInputs = [
             # GitHub Action Workflows.
             pkgs.yamlfmt