diff --git a/scripts/hak/hakEnv.js b/scripts/hak/hakEnv.js
index 265a41d2..22b915a3 100644
--- a/scripts/hak/hakEnv.js
+++ b/scripts/hak/hakEnv.js
@@ -44,6 +44,10 @@ function getTarget(packageJson) {
 
 function detectArch() {
     if (process.platform === 'win32') {
+        // vcvarsall.bat (the script that sets up the environment for
+        // visual studio build tools) sets an env var to tell us what
+        // architecture the active build tools target, so we auto-detect
+        // this.
         const targetArch = process.env.VSCMD_ARG_TGT_ARCH;
         if (targetArch === 'x86') {
             return 'ia32';