Proton, in your terminal.

Linux & macOS

curl -fsSL https://raw.githubusercontent.com/roman-16/proton-cli/main/scripts/install.sh | sh

Homebrew

brew install --cask roman-16/tap/proton-cli

Debian

sudo install -d -m 0755 /etc/apt/keyrings
curl -fsSL https://roman-16.github.io/proton-cli/gpg.key | sudo tee /etc/apt/keyrings/proton-cli.asc >/dev/null
echo "deb [signed-by=/etc/apt/keyrings/proton-cli.asc] https://roman-16.github.io/proton-cli stable main" | sudo tee /etc/apt/sources.list.d/proton-cli.list
sudo apt update && sudo apt install proton-cli

Arch

yay -S proton-cli-bin

Windows

irm https://raw.githubusercontent.com/roman-16/proton-cli/main/scripts/install.ps1 | iex

winget

winget install Roman-16.ProtonCLI

npm

npm install -g @roman-16/proton-cli

Nix

environment.systemPackages = [ pkgs.proton-cli ];

Real end-to-end encryption

SRP login and the full PGP key hierarchy, handled on your machine with Proton's own go-srp and gopenpgp. No bridge, no proxy, no browser in the middle.

Five apps, one binary

Mail, Drive, Calendar, Pass and Contacts, in a single static executable on Linux, macOS and Windows.

Built for pipes and cron

JSON and YAML with one envelope shape for every list, streaming stdin and stdout, exit codes that mean something, and --dry-run on everything that changes state.

What you can do

Every command reads the same way, proton <app> <collection> <verb>, and anywhere one wants an ID, a subject, name or URL works too.

Mail

Threads, attachments, filters, snoozing, block and allow lists, and auto-reply.

proton mail messages list --unread
proton mail messages get "Invoice #2291"
proton mail messages send --to alice@proton.me --subject Report --body "See attached."
proton mail messages reply "Invoice #2291" --body "Thanks, paid today."

Drive

Revisions, sharing with people, what others shared with you, and photo albums.

proton drive items list /Documents
proton drive items upload --recursive ./project /Backup
proton drive items download /Documents/report.pdf --output-dir .
proton drive items share link /Documents/report.pdf --expires 7d

Calendar

Recurring events occurrence by occurrence, all-day events, attendees, and .ics in and out.

proton calendar events list --start 2026-04-15 --end 2026-04-30
proton calendar events create --title Standup --start 2026-04-16T09:00 --duration 15m
proton calendar events respond "Team sync" --answer accept
proton calendar events export --start 2026-01-01 --end 2026-12-31 --output year.ics

Pass

Notes, cards, SSH keys, identities, two-factor codes, item history, and backups.

proton pass items list --vault Work
proton pass items get github.com
proton pass items create --name GitHub --username roman --url github.com
proton pass items totp github.com

Contacts

Typed addresses and phones, the full vCard field set, duplicate merging, and vCard import and export.

proton contacts list
proton contacts get jane
proton contacts create --name "Jane Roe" --email jane@example.com
proton contacts export --output-dir ./address-book