diff --git a/home/.chezmoidata/40-packages.yml b/home/.chezmoidata/40-packages.yml
index 714e977..76288e5 100644
--- a/home/.chezmoidata/40-packages.yml
+++ b/home/.chezmoidata/40-packages.yml
@@ -53,6 +53,8 @@ packages:
     - libtool
     - boost
     - pkgconf
+    # rustc wrapper; see ~/.cargo/config.toml
+    - sccache
 
     # DevOps & container tools
     # terraform was removed from homebrew-core (BSL license); use opentofu,
diff --git a/home/dot_bunfig.toml b/home/dot_bunfig.toml
new file mode 100644
index 0000000..2d24b79
--- /dev/null
+++ b/home/dot_bunfig.toml
@@ -0,0 +1,6 @@
+# ~/.bunfig.toml
+# Managed by chezmoi — bun installs by hardlinking from its own cache instead
+# of copying every package into each node_modules. Nothing else changes: the
+# trees look and behave identically, they just stop being separate copies.
+[install]
+backend = "hardlink"
diff --git a/home/dot_cargo/config.toml b/home/dot_cargo/config.toml
new file mode 100644
index 0000000..1c58250
--- /dev/null
+++ b/home/dot_cargo/config.toml
@@ -0,0 +1,11 @@
+# ~/.cargo/config.toml
+# Managed by chezmoi — rustc compiles through sccache, a cache keyed by
+# compilation inputs, so the same dependency crate is built once per machine
+# rather than once per checkout.
+#
+# Deliberately NOT a shared [build] target-dir: cargo takes an exclusive lock
+# on the directory it builds into, so pointing several checkouts at one dir
+# would serialise every build that runs in parallel today. sccache is safe for
+# concurrent readers and writers; target dirs stay per-project.
+[build]
+rustc-wrapper = "sccache"
diff --git a/home/dot_config/ghostty/config.ghostty b/home/dot_config/ghostty/config.ghostty
index 6dc8fdd..55d5b5a 100644
--- a/home/dot_config/ghostty/config.ghostty
+++ b/home/dot_config/ghostty/config.ghostty
@@ -57,6 +57,7 @@ shell-integration-features = cursor,title,ssh-env,path
 command = direct:tmux new-session -A -s main
 
 # Raycast Hyper (Ctrl+Option+Command) to tmux prefix C-a plus command.
+keybind = ctrl+alt+super+space=text:\x01
 keybind = ctrl+alt+super+c=text:\x01c
 keybind = ctrl+alt+super+i=text:\x01|
 keybind = ctrl+alt+super+Slash=text:\x01-
diff --git a/home/dot_config/tmux/tmux.conf b/home/dot_config/tmux/tmux.conf
index 595f9ec..ed6e75f 100644
--- a/home/dot_config/tmux/tmux.conf
+++ b/home/dot_config/tmux/tmux.conf
@@ -18,7 +18,7 @@ set -g set-clipboard on
 set -g history-limit 100000
 
 # Ghostty Hyper bindings send the prefix and command in one write.
-set -s assume-paste-time 0
+set -g assume-paste-time 0
 
 # Vim copy mode
 setw -g mode-keys vi
diff --git a/test.sh b/test.sh
index acaca49..2446db9 100755
--- a/test.sh
+++ b/test.sh
@@ -97,9 +97,11 @@ grep -Fq "alias conftmux='chezmoi edit --apply ~/.config/tmux/tmux.conf'" home/d
 grep -Fq 'command = direct:tmux new-session -A -s main' home/dot_config/ghostty/config.ghostty || fail "Ghostty must resolve tmux through PATH"
 grep -Fq 'keybind = super+k=text:\x0c' home/dot_config/ghostty/config.ghostty || fail "missing tmux-aware Command-K binding"
 grep -Fq 'keybind = shift+enter=unbind' home/dot_config/ghostty/config.ghostty || fail "legacy Shift-Enter paste binding must be removed"
+grep -Fq 'keybind = ctrl+alt+super+space=text:\x01' home/dot_config/ghostty/config.ghostty || fail "Hyper-Space must send the reusable tmux prefix"
 grep -Fq 'xterm-ghostty:RGB:extkeys' home/dot_config/tmux/tmux.conf || fail "Ghostty must advertise extended keys to tmux"
 grep -Fq 'set -s extended-keys on' home/dot_config/tmux/tmux.conf || fail "tmux must pass modified keys to Claude Code"
 grep -Fq 'set -g focus-events on' home/dot_config/tmux/tmux.conf || fail "tmux must pass focus events to Claude Code"
+grep -Fq 'set -g assume-paste-time 0' home/dot_config/tmux/tmux.conf || fail "tmux must disable paste timing as a global session option"
 if find home/private_dot_ssh -type f ! -name config -print -quit | grep -q .; then
   fail "SSH key material must not be managed"
 fi