diff --git a/go.mod b/go.mod
index f1cadb43..ac419f73 100644
--- a/go.mod
+++ b/go.mod
@@ -7,7 +7,7 @@ require (
 	charm.land/bubbletea/v2 v2.0.9
 	charm.land/glamour/v2 v2.0.1
 	charm.land/lipgloss/v2 v2.0.6
-	github.com/basecamp/actioncable-go v1.1.0
+	github.com/basecamp/actioncable-go v1.2.0
 	github.com/basecamp/hey-sdk/go v0.31.1
 	github.com/basecamp/mcp v0.0.0-20260828100356-2d6f44b51e9d
 	github.com/charmbracelet/x/ansi v0.11.8
diff --git a/go.sum b/go.sum
index 656af9d5..6d487a1b 100644
--- a/go.sum
+++ b/go.sum
@@ -87,8 +87,8 @@ github.com/aymanbagabas/go-udiff v0.4.1 h1:OEIrQ8maEeDBXQDoGCbbTTXYJMYRCRO1fnodZ
 github.com/aymanbagabas/go-udiff v0.4.1/go.mod h1:0L9PGwj20lrtmEMeyw4WKJ/TMyDtvAoK9bf2u/mNo3w=
 github.com/aymerick/douceur v0.2.0 h1:Mv+mAeH1Q+n9Fr+oyamOlAkUNPWPlA8PPGR0QAaYuPk=
 github.com/aymerick/douceur v0.2.0/go.mod h1:wlT5vV2O3h55X9m7iVYN0TBM0NH/MmbLnd30/FjWUq4=
-github.com/basecamp/actioncable-go v1.1.0 h1:AizmCxoKvmUMdqwMQCCLQrFaVbjp8RhkneWidxygc7E=
-github.com/basecamp/actioncable-go v1.1.0/go.mod h1:ezaV5z1GXQAsqyejqTs6wCFl2D8Wj+COLQkHc/kwoRs=
+github.com/basecamp/actioncable-go v1.2.0 h1:t0MxlfMTcmaGXZ5ztgKRs7ZiY1MwXtBRwSSSAh1ofVg=
+github.com/basecamp/actioncable-go v1.2.0/go.mod h1:ezaV5z1GXQAsqyejqTs6wCFl2D8Wj+COLQkHc/kwoRs=
 github.com/basecamp/hey-sdk/go v0.31.1 h1:dFlCe4LMmLAHgRB05QRHaE26XPPkZVIMp0qCGEanVQU=
 github.com/basecamp/hey-sdk/go v0.31.1/go.mod h1:eCJOhTLOpi2FCQUXireHZQ7DzRs2TUqvYhRDTfVLoDY=
 github.com/basecamp/mcp v0.0.0-20260828100356-2d6f44b51e9d h1:zEQVGq1x1nhKMZ2TudFAcSJ32CHT8richI1vQakIKz4=
diff --git a/nix/package.nix b/nix/package.nix
index b361d2a6..af92023d 100644
--- a/nix/package.nix
+++ b/nix/package.nix
@@ -18,7 +18,7 @@ buildGoModule.override { inherit go; } (finalAttrs: {
 
   # To update: run `make update-nix-hash` (Docker). It rewrites this quoted
   # value in place, so keep it a string literal rather than lib.fakeHash.
-  vendorHash = "sha256-ZfLot6LMYS4yL+5A4Jb9qzNVRobgUuVqXkuWfnX751k=";
+  vendorHash = "sha256-LWfEAlwWE7YbR7MHAYviBDnaNJ32CpMwXE2p4LdgA64=";
 
   subPackages = [ "cmd/hey" ];