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HermitStash

Post-quantum encrypted self-hosted file sharing

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Version1.13.9
Source codePublic
Developed bydotCooCoo1 app
Submitted bydotCooCoo1 app
Compatible withumbrelOS 0.5 or later

HermitStash is a self-hosted file upload server with post-quantum encryption. Every file and database field is sealed with an ML-KEM-1024 + ECDH P-384 hybrid envelope and XChaCha20-Poly1305 before touching disk; passwords use Argon2id. Nothing is stored in plaintext, including database fields the operator never thinks of as sensitive.

Generate shareable download links with optional expiry, download limits, and per-bundle passwords. Sign in with WebAuthn passkeys, mTLS browser certificates issued by the built-in CA, or password + TOTP. A separately-installable desktop sync client watches a local folder and mirrors changes back to the server over a post-quantum WebSocket channel.

The admin panel covers users, uploads, webhooks, API keys, branding, and storage backends — local disk by default, or any S3-compatible bucket (MinIO, Cloudflare R2, Backblaze B2) for off-device archives. Retry-safe writes via the standard Idempotency-Key header. RFC 9457 problem-details on every API error response.

Files and database fields are sealed with post-quantum encryption at rest no matter how you reach the app. When it is served over HTTPS — a custom domain, or remote access over Tor or Tailscale — the TLS handshake also negotiates a post-quantum key exchange (X25519MLKEM768 or SecP384r1MLKEM1024), so the connection itself is quantum-resistant; over a plain local-network address the at-rest protection still applies.

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