From 1f137e92d32081809de611d530e2ad464fddf8bf Mon Sep 17 00:00:00 2001
From: Lann Martin <lmartin@akamai.com>
Date: Mon, 7 Sep 2026 11:40:01 -0400
Subject: [PATCH] boot: derive the home origin from the page URL, not
 location.origin

A GitHub Pages project site is served under /<repo>/, so the kernel's
{home-origin}/apps/index.json fetch went to the host root and 404ed.
Every other URL the tab and worker resolve is already relative to
location.href; the hello now matches.
---
 runtime/wit/internal.wit | 5 +++--
 web/boot.ts              | 5 ++++-
 web/worker.ts            | 4 ++--
 3 files changed, 9 insertions(+), 5 deletions(-)

diff --git a/runtime/wit/internal.wit b/runtime/wit/internal.wit
index 08999973..365b003a 100644
--- a/runtime/wit/internal.wit
+++ b/runtime/wit/internal.wit
@@ -119,8 +119,9 @@ interface lifecycle {
 
     record boot-config {
         /// The home origin, as an absolute URL without a trailing slash.
-        /// Release artifacts and, until installation lands, app bundles are
-        /// fetched from it.
+        /// It may carry a path (a GitHub Pages project site is served
+        /// under `/<repo>/`). Release artifacts and, until installation
+        /// lands, app bundles are fetched from it.
         home-origin: string,
         /// The device this worker is: the glue's sessionStorage anchor, or
         /// an id the glue minted for a fresh device. The glue names the
diff --git a/web/boot.ts b/web/boot.ts
index 388f0cdf..d40f9e4b 100644
--- a/web/boot.ts
+++ b/web/boot.ts
@@ -257,7 +257,10 @@ fetch(new URL("config.json", location.href), { cache: "no-store" })
     control.postMessage({
       t: "hello",
       device,
-      homeOrigin: location.origin,
+      // The directory this page is served from, not `location.origin`: a
+      // GitHub Pages project site lives under `/<repo>/`, and the kernel
+      // fetches `{home-origin}/apps/...`, so the prefix must be kept.
+      homeOrigin: new URL(".", location.href).href.replace(/\/$/, ""),
       relay,
       // The OAuth redirect (`lifecycle.boot-config.page-url`): this page's
       // URL without query or fragment, which is where the popup comes back
diff --git a/web/worker.ts b/web/worker.ts
index adb005f4..c2a9bec9 100644
--- a/web/worker.ts
+++ b/web/worker.ts
@@ -262,8 +262,8 @@ const ready: Promise<Exports> = (async () => {
       driveOauth: string | undefined;
     },
   ) => Promise<void>;
-  // The home origin without a trailing slash, per `lifecycle.boot-config`.
-  // `location.origin` is spelled that way, and every tab that can reach this
+  // The home origin without a trailing slash, per `lifecycle.boot-config`;
+  // the tab derives it from its own URL, and every tab that can reach this
   // worker is on the home origin by construction.
   // `option<string>` lowers as `T | undefined` (m1-context.md "Value
   // mapping"), so an absent base is passed as the absence itself rather