diff --git a/pkgs/development/compilers/jetbrains-jdk/17.nix b/pkgs/development/compilers/jetbrains-jdk/17.nix
index e802385888e14..61482ac1f0ea8 100644
--- a/pkgs/development/compilers/jetbrains-jdk/17.nix
+++ b/pkgs/development/compilers/jetbrains-jdk/17.nix
@@ -60,7 +60,7 @@ openjdk17.overrideAttrs (oldAttrs: rec {
     hash = "sha256-Ckv2SNugHK75Af+ZzI91+QodOHIa5TMcjVQYsO45mQo=";
   };
 
-  env = {
+  env = (oldAttrs.env or { }) // {
     BOOT_JDK = openjdk17-bootstrap.home;
     # run `git log -1 --pretty=%ct` in jdk repo for new value on update
     SOURCE_DATE_EPOCH = 1745907200;
diff --git a/pkgs/development/compilers/jetbrains-jdk/default.nix b/pkgs/development/compilers/jetbrains-jdk/default.nix
index b76186cd7b9bc..37c94fffcf7ce 100644
--- a/pkgs/development/compilers/jetbrains-jdk/default.nix
+++ b/pkgs/development/compilers/jetbrains-jdk/default.nix
@@ -62,7 +62,7 @@ jdk.overrideAttrs (oldAttrs: rec {
     hash = "sha256-P2boCbGB66X8LB4sZHGFO8lqHbv6F4kqGVMGBd9yKu0=";
   };
 
-  env = {
+  env = (oldAttrs.env or { }) // {
     BOOT_JDK = jdk.home;
     # run `git log -1 --pretty=%ct` in jdk repo for new value on update
     SOURCE_DATE_EPOCH = 1765114563;