diff --git a/public/install.sh b/public/install.sh
index caf9ec5..2aa814a 100755
--- a/public/install.sh
+++ b/public/install.sh
@@ -21,6 +21,11 @@ have() { command -v "$1" >/dev/null 2>&1; }
 say "Installing crawlproof (CrawlProof CLI)..."
 
 if have bun; then
+  # bun add -g writes into the nearest package.json above its global dir when
+  # that dir has none (e.g. ~/package.json): give it its own first.
+  BUN_GLOBAL="${BUN_INSTALL:-$HOME/.bun}/install/global"
+  mkdir -p "$BUN_GLOBAL"
+  [ -f "$BUN_GLOBAL/package.json" ] || printf '{}\n' > "$BUN_GLOBAL/package.json"
   bun add -g "$PKG@latest"
   BIN_DIR="${BUN_INSTALL:-$HOME/.bun}/bin"
 elif have npm && have node; then