diff --git a/setup.py b/setup.py
index 4ab2c8f..2cee2e1 100644
--- a/setup.py
+++ b/setup.py
@@ -108,5 +108,5 @@ if os.getenv("LOCALAPPDATA") is not None:
 if os.getenv("CODER_WORKSPACE_ID"):
     subprocess.run(["sudo", "add-apt-repository", "ppa:kelleyk/emacs", "-y"])
     subprocess.run(["sudo", "apt-get", "update"])
-    subprocess.run(["sudo", "apt-get", "install", "-y", "fish", "emacs27-nox"])
+    subprocess.run(["sudo", "apt-get", "install", "-y", "fish", "emacs27-nox", "tmux"])
     subprocess.run(["sudo", "chsh", "-s", "/usr/bin/fish", os.getenv("USER")])