From 2fae3b5f648224b02c20d7abcc6550f2d4932b41 Mon Sep 17 00:00:00 2001
From: OdWar420 <12932901+OdWar420@users.noreply.github.com>
Date: Tue, 9 Jun 2026 22:12:24 +0200
Subject: [PATCH] perf(http): gzip-compress text responses (#3690)
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

The frontend's text assets shipped uncompressed on every cold load. Add
Starlette's GZipMiddleware. Measured on the current assets:

- style.css   1,127 KB -> 238 KB  (-79%)
- index.html    202 KB ->  35 KB  (-83%)
- chat.js       238 KB ->  60 KB  (-75%)

minimum_size=1024 skips tiny bodies; Starlette excludes `text/event-stream` by
default, so the SSE streams (chat, shell, research, model-probe — all served with
media_type="text/event-stream") are never compressed or buffered. Composes
cleanly with the existing security-header middleware. No behavioural change.

Built by OdWar -- with Claude thinking alongside.
---
 app.py | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/app.py b/app.py
index abd49e26b..cfd73e83f 100644
--- a/app.py
+++ b/app.py
@@ -47,6 +47,7 @@ from fastapi.responses import JSONResponse, FileResponse, HTMLResponse
 from fastapi.middleware.cors import CORSMiddleware
 from fastapi.staticfiles import StaticFiles
 from starlette.middleware.base import BaseHTTPMiddleware
+from starlette.middleware.gzip import GZipMiddleware
 
 # Core imports
 from core.constants import (
@@ -104,6 +105,16 @@ app.add_middleware(
     ],
 )
 
+# ========= RESPONSE COMPRESSION (gzip) =========
+# The frontend's text assets (style.css, index.html, the JS bundles) shipped
+# uncompressed on every cold load. gzip cuts CSS/JS/HTML by ~75-85% on the wire
+# with no behavioural change. Starlette's GZipMiddleware excludes
+# `text/event-stream` by default, so the SSE streams (chat, shell, research,
+# model-probe — all served with media_type="text/event-stream") are never
+# compressed or buffered; only complete bodies over minimum_size are. The
+# security-header middleware composes cleanly on top.
+app.add_middleware(GZipMiddleware, minimum_size=1024, compresslevel=6)
+
 # ========= SECURITY HEADERS MIDDLEWARE =========
 app.add_middleware(SecurityHeadersMiddleware)