diff --git a/pkgs/by-name/si/simdjson/package.nix b/pkgs/by-name/si/simdjson/package.nix
index de01315c7b0b..f8f355c7ecce 100644
--- a/pkgs/by-name/si/simdjson/package.nix
+++ b/pkgs/by-name/si/simdjson/package.nix
@@ -7,13 +7,13 @@
 
 stdenv.mkDerivation (finalAttrs: {
   pname = "simdjson";
-  version = "4.1.0";
+  version = "4.2.1";
 
   src = fetchFromGitHub {
     owner = "simdjson";
     repo = "simdjson";
     tag = "v${finalAttrs.version}";
-    hash = "sha256-N3NPE9R8VipspCwH2dY339WUGt51aqkYpLTr/PPVRQ4=";
+    hash = "sha256-EuineRyNSwWoMRuev6ZFQNeFgSHjuoHhoGhYD0ls6GQ=";
   };
 
   nativeBuildInputs = [ cmake ];