docs: record frontend migration baseline

2026-08-01 12:09:38 +02:00
parent e6f593b959
commit 42e5dc8604
2 changed files with 65 additions and 1 deletions
@@ -0,0 +1,50 @@
+<!--
+SPDX-FileCopyrightText: 2026 Stan Grams <sjg@haxx.space>
+
+SPDX-License-Identifier: GPL-2.0-or-later
+-->
+
+# TypeScript migration baseline
+
+This baseline records the browser architecture at the start of the migration.
+It is intentionally historical; generated output sizes are tracked separately
+by the deterministic frontend build.
+
+## Startup order
+
+The initial document loads these scripts in order:
+
+1. `/vendor/opus-decoder-0.7.11.min.js`
+2. `/vendor/leaflet.js`
+3. `/leaflet-ais-tracksymbol.js`
+4. `/webgl-renderer.js`
+5. `/ui-core.js`
+6. `/app.js`
+
+Decoder and feature scripts are then loaded lazily by the inline loader in
+`index.html`. The frontend smoke test locks the core ordering and rejects
+remote script or stylesheet URLs.
+
+## Source measurements
+
+At baseline, first-party JavaScript comprised 23 files and approximately
+776 KiB. The largest sources were:
+
+| Source | Bytes |
+|---|---:|
+| `app.js` | 337,111 |
+| `map-core.js` | 131,899 |
+| `plugins/scheduler.js` | 60,883 |
+| `plugins/bookmarks.js` | 30,543 |
+| `plugins/sat.js` | 22,541 |
+| `plugins/vchan.js` | 20,195 |
+| `webgl-renderer.js` | 18,993 |
+
+The migrated source snapshot contained 123 distinct direct `window.*`
+assignments. These are compatibility callbacks, shared state, and plugin entry
+points. New TypeScript code must not add to that set; the typed plugin registry
+and explicit services replace it over the course of the migration.
+
+All production scripts, stylesheets, fonts, icons, and map assets were already
+served from local embedded routes. The automated startup test ensures no
+remote runtime script or stylesheet dependency is introduced.