Core concepts

Security model

packshell is built so that trusting the server is never required. Here is exactly what is encrypted, what is stored, and what is not.

Cryptography

Environment encryption: AES-256-GCM, an authenticated cipher, applied to the full .env contents with the project key. Output is tagged aes-256-gcm:.
Key wrapping: RSA-OAEP with 4096-bit keys and SHA-256, used to encrypt the project key for each member. Output is tagged rsa-oaep:. The algorithm identifier recorded is RSA-OAEP-4096-SHA256.
Integrity: a SHA-256 checksum is computed per version so changes are detectable without revealing contents.

What the server stores

StoredWhy

Cipher blobs (aes-256-gcm:)to sync encrypted versions

Wrapped project keys (rsa-oaep:)to grant per-member access

SHA-256 checksums + key countsintegrity & diff metadata

Member public keysso others can wrap keys for them

Audit log entriesaccountability for team actions

What the server never sees

Never stored or transmitted in plaintext

✕ Plaintext .env contents

✕ Individual secret values

✕ Project keys (only wrapped forms are stored)

✕ Your RSA private key (it never leaves your machine)

Your private key is yours to protectBecause decryption depends on your local private key, packshell cannot recover your secrets if you lose it. Re-authenticating issues a fresh keypair; teammates then re-share project keys to your new public key.

Diffs without disclosure

packshell diff compares the keys present locally versus remotely — added, removed, or changed names — without ever printing or transmitting values. It works from checksums and key metadata, so you can review what a push will change safely.

terminal

$ packshell diff --env production

Threat model in one line

A fully compromised packshell server yields cipher blobs and wrapped keys an attacker cannot open without a member's private key. Compromise reduces to the endpoints, which is where it belongs.