diff --git a/modules/nixos/profiles/dev.nix b/modules/nixos/profiles/dev.nix
index c8cd1471..e8e27949 100644
--- a/modules/nixos/profiles/dev.nix
+++ b/modules/nixos/profiles/dev.nix
@@ -89,6 +89,7 @@ in {
         diffoscope # Oversized caffeine grinder.
         direnv # The power of local development environment.
         ipcalc # Calculate your IP without going to the web.
+        lsof # View every single open connections.
         gcc # The usual toolchain.
         gdb # The usual debugger.
         gnumake # The other poster boy for the hated build system.