diff --git a/nix/packages/by-name/tmux-sessionizer/package.nix b/nix/packages/by-name/tmux-sessionizer/package.nix
index 63ebfc67..63c7cbc1 100644
--- a/nix/packages/by-name/tmux-sessionizer/package.nix
+++ b/nix/packages/by-name/tmux-sessionizer/package.nix
@@ -8,24 +8,6 @@
   symlinkJoin,
 }:
 let
-  tmux-register-session = writeShellApplication {
-    name = "__tmux-register-session";
-    runtimeInputs = [ tmux ];
-    text = ''
-      last=/tmp/TMUX_LAST
-
-      # bail if tmux not running
-      if ! pgrep tmux >/dev/null 2>&1; then
-        exit 1
-      fi
-
-      this="$(tmux display-message -p '#S')"
-      if [ ! -f "$last" ] || [ "$(cat "$last")" != "$this" ]; then
-          echo "$this" >"$last"
-      fi
-    '';
-  };
-
   tmux-maybe-create = writeShellApplication {
     name = "__tmux-maybe-create";
     runtimeInputs = [
@@ -94,7 +76,6 @@ let
       esac
 
       # effects
-      ${lib.getExe tmux-register-session} || :
       ${lib.getExe tmux-maybe-create} "$session_name" "$selected"
       ${lib.getExe tmux-attach-or-switch} "$session_name"
     '';
@@ -103,7 +84,6 @@ in
 symlinkJoin {
   name = "tmux-sessionizer";
   paths = [
-    tmux-register-session
     tmux-maybe-create
     tmux-attach-or-switch
     tmux-sessionizer