rudeshark.net/packages/backend/src/server/web/manifest.ts

import Koa from 'koa';
import * as manifest from './manifest.json';
import { fetchMeta } from '@/misc/fetch-meta.js';

export const manifestHandler = async (ctx: Koa.Context) => {
	const json = JSON.parse(JSON.stringify(manifest));

	const instance = await fetchMeta(true);

	json.short_name = instance.name || 'Misskey';
	json.name = instance.name || 'Misskey';
	if (instance.themeColor) json.theme_color = instance.themeColor;

	ctx.set('Cache-Control', 'max-age=300');
	ctx.body = json;
};