From 366c44d5c2b9c734bedc257fbabe292788a71f2e Mon Sep 17 00:00:00 2001
From: catloversg <152669316+catloversg@users.noreply.github.com>
Date: Thu, 29 Jan 2026 03:10:13 +0700
Subject: [PATCH] API: Add warning when installing backdoor on backdoored
 server with Singularity API (#2458)

---
 src/NetscriptFunctions/Singularity.ts | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/src/NetscriptFunctions/Singularity.ts b/src/NetscriptFunctions/Singularity.ts
index d66a48eb3..22b04a3ff 100644
--- a/src/NetscriptFunctions/Singularity.ts
+++ b/src/NetscriptFunctions/Singularity.ts
@@ -529,6 +529,14 @@ export function NetscriptSingularity(): InternalAPI<ISingularity> {
         throw helpers.errorMessage(ctx, canHack.msg || "");
       }
 
+      if (server.backdoorInstalled) {
+        helpers.log(
+          ctx,
+          () =>
+            "You have already installed a backdoor on this server. You can check if the server has a backdoor installed " +
+            "with ns.getServer().backdoorInstalled.",
+        );
+      }
       helpers.log(
         ctx,
         () => `Installing backdoor on '${server.hostname}' in ${convertTimeMsToTimeElapsedString(installTime, true)}`,