Ferrum

FerrumEnv

Alpha

A password-locked vault for your projects' environment variables, with encrypted sharing between developers.

Your projects' environment variables in one encrypted file instead of loose .env files. Share them with a teammate as an encrypted bundle, sealed with a key you exchange once.

Download LauncherInstall with Ferrum Launcher

Security model

What the encryption protects, and what it can't. Both lists come from FerrumEnv's own documentation. The security page has the details.

How the vault is protected

  • The vault key comes from your master password through Argon2id (64 MiB, 3 passes) and a random salt.
  • The whole vault, project names included, is sealed with XChaCha20-Poly1305 under a fresh nonce on every save. Only the file header is readable on disk.
  • A wrong password, a modified file or a newer format is reported as an error, not a crash.
  • Saves are atomic, with mode 0600 in a 0700 folder. The previous file is kept as an encrypted backup.
  • Bundles are sealed with the project's share key and bound to the project name. The key itself is never inside a bundle.
  • Values and keys are wiped from memory when they're dropped and are never logged. Locking drops the whole unlocked state.

Limits

  • Wiping memory is best effort: some copies (JSON parsing, text fields, text layout) are freed but not zeroed. Swap and core dumps are not prevented.
  • A copied value is outside the app's control while it's on the clipboard, and clipboard managers may keep it. Exported .env files are plain text.
  • There is no protection against malware running as your user, such as keyloggers or memory readers.
  • Anyone with a project's share key can read and create bundles for that project. Rotating the key only affects future bundles.
  • There is no recovery: if you forget the master password, the data is gone.

What FerrumEnv does

The encryption, bundles and .env parsing are unit-tested; the window is covered by headless tests.

  • Locked by default

    The master password is asked on every start, and nothing is decrypted before. The vault locks after 30 minutes without activity (or 5, 15 or 60), and ⌘L locks it at once.

  • Projects and environments

    A project links to a folder and starts with development, staging and production. Each variable has a key, a value, an optional comment and a secret flag.

  • Secrets stay masked

    Reveal one value or all of them. A copied value is cleared from the clipboard after 30 s if it's still there, and at once when the vault locks.

  • Encrypted bundles

    Share all or chosen environments as encrypted text or a .fenv file. Before an import, you see what will be added, changed or removed, by key name only.

  • Share keys you can check

    Each project has a 256-bit key shown as fek1_…, with a checksum that rejects typos and a short fingerprint to compare out loud. Rotate it to cut someone off from future bundles.

  • .env in and out

    Import .env, .env.local, .env.production and the rest from a project folder. Write an environment back to a .env file with mode 0600, copy it as text, or compare two environments.

Status: Alpha

FerrumEnv is in alpha. Its tests are automated; the app hasn't been clicked through by hand yet.

Works today

  • Master password, auto-lock and ⌘L
  • Projects, environments and variables, with search
  • Masked secrets, reveal, and copy with clipboard clearing
  • Share keys, and encrypted bundles as text or .fenv files
  • .env import and export, and comparing two environments
  • Changing the master password in Settings

Not built yet

  • Undo and per-variable history
  • A command-line tool that runs a command with the variables set
  • Unlocking with Touch ID or the OS keychain
  • Per-person public keys instead of one shared key per project
  • Drag and drop of .env and .fenv files, and opening .fenv files from Finder

Requirements & built with

Install
Ferrum Launcher (free, see Download)
Shell command
fev, turned on in Ferrum Launcher
Vault file
~/.ferrum/env/vault.json, encrypted
Built with
Rust, GPUI, Argon2id, XChaCha20-Poly1305, zeroize
Tested with
Automated unit tests and headless window tests, not yet by hand

A forgotten master password can't be reset. Keep it somewhere safe.