diff --git a/build-support/typescript-compile.coffee b/build-support/typescript-compile.coffee
index be156974a2..5a1ef20f89 100644
--- a/build-support/typescript-compile.coffee
+++ b/build-support/typescript-compile.coffee
@@ -5,7 +5,7 @@
 # support for it, but it seems appropriate to focus on coffeescript itself first.
 
 '''
-# e.g. run these shell commands from the repo root:
+# e.g. run these shell commands from the repo root (you'll need to have npm installed typescript):
 ; cat > test-map.coffee <<EOF
 y = 3
 
diff --git a/package-lock.json b/package-lock.json
index 77920e4a60..2172931b9e 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -22,6 +22,7 @@
         "jison": "~0.4.18",
         "markdown-it": "~13.0.0",
         "puppeteer": "~13.6.0",
+        "typescript": "^5.7.2",
         "underscore": "~1.13.3",
         "webpack": "~5.72.0"
       },
@@ -3929,6 +3930,20 @@
       "integrity": "sha512-i/6DQjL8Xf3be4K/E6Wgpekn5Qasl1usyw++dAA35Ue5orEn65VIxOA+YvNNl9HV3qv70T7CNwjODHZrLwvd1Q==",
       "dev": true
     },
+    "node_modules/typescript": {
+      "version": "5.7.2",
+      "resolved": "https://registry.npmjs.org/typescript/-/typescript-5.7.2.tgz",
+      "integrity": "sha512-i5t66RHxDvVN40HfDd1PsEThGNnlMCMT3jMUuoh9/0TaqWevNontacunWyN02LA9/fIbEWlcHZcgTKb9QoaLfg==",
+      "dev": true,
+      "license": "Apache-2.0",
+      "bin": {
+        "tsc": "bin/tsc",
+        "tsserver": "bin/tsserver"
+      },
+      "engines": {
+        "node": ">=14.17"
+      }
+    },
     "node_modules/uc.micro": {
       "version": "1.0.6",
       "resolved": "https://registry.npmjs.org/uc.micro/-/uc.micro-1.0.6.tgz",
@@ -7091,6 +7106,12 @@
       "integrity": "sha512-i/6DQjL8Xf3be4K/E6Wgpekn5Qasl1usyw++dAA35Ue5orEn65VIxOA+YvNNl9HV3qv70T7CNwjODHZrLwvd1Q==",
       "dev": true
     },
+    "typescript": {
+      "version": "5.7.2",
+      "resolved": "https://registry.npmjs.org/typescript/-/typescript-5.7.2.tgz",
+      "integrity": "sha512-i5t66RHxDvVN40HfDd1PsEThGNnlMCMT3jMUuoh9/0TaqWevNontacunWyN02LA9/fIbEWlcHZcgTKb9QoaLfg==",
+      "dev": true
+    },
     "uc.micro": {
       "version": "1.0.6",
       "resolved": "https://registry.npmjs.org/uc.micro/-/uc.micro-1.0.6.tgz",
diff --git a/package.json b/package.json
index 06348d75b7..ee35334c4e 100644
--- a/package.json
+++ b/package.json
@@ -49,6 +49,7 @@
     "jison": "~0.4.18",
     "markdown-it": "~13.0.0",
     "puppeteer": "~13.6.0",
+    "typescript": "^5.7.2",
     "underscore": "~1.13.3",
     "webpack": "~5.72.0"
   }