diff --git a/pkgs/by-name/h2/h2o/package.nix b/pkgs/by-name/h2/h2o/package.nix
index 50c75914d5f4..c09184ce77d8 100644
--- a/pkgs/by-name/h2/h2o/package.nix
+++ b/pkgs/by-name/h2/h2o/package.nix
@@ -7,6 +7,7 @@
   makeWrapper,
   ninja,
   perl,
+  perlPackages,
   brotli,
   openssl,
   libcap,
@@ -44,6 +45,7 @@ stdenv.mkDerivation (finalAttrs: {
     cmake
     makeWrapper
     ninja
+    perlPackages.JSON
   ]
   ++ lib.optionals withMruby [
     bison
@@ -72,6 +74,9 @@ stdenv.mkDerivation (finalAttrs: {
         --set "H2O_PERL" "${lib.getExe perl}" \
         --prefix "PATH" : "${lib.getBin openssl}/bin"
     done
+
+    wrapProgram "$out/bin/h2olog" \
+        --set "PERL5LIB" "$PERL5LIB"
   '';
 
   passthru = {