diff --git a/flake.nix b/flake.nix
index c39edfc..a7bb9fc 100644
--- a/flake.nix
+++ b/flake.nix
@@ -118,6 +118,7 @@
           lockFile = ./Cargo.lock;
           outputHashes = {
               "core_io-0.1.20210325" = "sha256-JLlEMx9C0pWVae8Vucm7FqMViwUoA2rRbJyYM9r0s8M=";
+              "fatfs-0.3.5" = "sha256-0ta9IgRyi2tG3Xzm2D6WMdGSMMgRvVThyY2W4k60VwM=";
             };
         };