The global `script-src 'self'` CSP header blocked every inline <script>,
so the SvelteKit hydration bootstrap never ran and the SPA never mounted
(blank page behind the splash spinner). The anti-FOUC theme init in
app.html was blocked too.
Instead of weakening the policy with 'unsafe-inline', the backend now
builds `script-src` at startup from 'self' plus a SHA-256 hash of every
inline <script> in the served HTML shells. The policy stays strict (no
'unsafe-inline' for scripts) and the hashes are recomputed from the built
assets on each startup, so a frontend rebuild needs no header edit — even
though SvelteKit's bootstrap hash changes every build.
- web::content_security_policy builds the header; web::resolve_static_path
is extracted so serving and hashing read the exact same bytes.
- byte-exact inline-script extraction (skips src= externals), unit-tested
against a known SHA-256 vector and extraction edge cases.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
DioCrafts
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