Open protocol · End-to-end encrypted · Self-hostable
Private conversations on a network no one owns.
Lumen is secure messaging built on the open Matrix protocol. Messages are encrypted on your devices before they leave them. Servers relay ciphertext, talk to each other through federation, and can be run by anyone — including you.
Honest privacy
What our servers can and cannot see
Encryption protects what you say. It cannot hide that you are talking. We publish both sides so you can decide what fits your threat model.
Cannot read
- Message text, replies and reactions in encrypted rooms
- Files and images you share in encrypted rooms
- Your message keys and your recovery key
- Your encrypted key backup (encrypted with a key only you hold)
Can see (metadata)
- Your account name, email address and sign-in times
- Which rooms you are in, who else is in them, and when messages are sent
- IP addresses of your devices and of servers we federate with
- Room names and topics are visible to servers in that room
Everything you need
Serious security, without the homework
The cryptography is the battle-tested Matrix stack. The experience is designed so that people who never think about keys still end up safe.
Encrypted chats and groups
Direct messages and group rooms are end-to-end encrypted by default, with replies, reactions, read receipts and typing indicators.
Verified people and devices
Compare emoji on two screens to verify a contact. Cross-signing means you verify a person once, not every device they own.
Recovery you control
An encrypted backup of your message keys, unlocked by a recovery key that only you hold. Lose a phone, not your history.
Federated by design
Talk to anyone on any compatible Matrix server. No single company — including us — is the network.
Workspaces for teams
Invite colleagues, manage roles, and require two-factor authentication before anyone can sign in to chat.
Encrypted files
Attachments are encrypted in your browser before upload. The server stores bytes it cannot open.
Get going in minutes
Three steps to a private conversation
Create your account
Pick a username — it becomes your address, @you:0r834h.duckdns.org. Turn on two-factor authentication while you're there.
Open the chat app and save your recovery key
Your device creates its keys locally. Save the recovery key somewhere safe: it is the only way to restore encrypted history on a new device.
Start a chat and verify
Message anyone by their Matrix address, then verify each other with a quick emoji comparison.
Zero-trust architecture
Every boundary authenticates
The website, customer portal, homeserver, database and operator console run as separate services with separate credentials. The operator console is not on the public internet at all. Billing never touches conversations.
- Encryption happens on your devices — never on our servers
- Operator access requires MFA, a private network path and is audit-logged
- No hidden admin accounts, no default passwords, no backdoors
Pricing
Start free. Upgrade when your team grows.
Free
For individuals and small groups getting started.
- End-to-end encrypted direct and group chats
- Device verification and encrypted key backup
- Federation with other Matrix servers
- Workspace with up to 5 members
- 25 MB files, 1 GB of uploads per member every 30 days
Pro
For teams that need room to grow.
- Everything in Free
- Up to 50 members
- 100 MB files, 10 GB of uploads per member every 30 days
- Require two-factor authentication for every member
Business
For organisations with stricter requirements.
- Everything in Pro
- Up to 500 members
- 250 MB files, 50 GB of uploads per member every 30 days
- Priority support queue
Own your infrastructure
Run your own Lumen server
Everything that powers this service — website, portal, homeserver, web chat, backups and monitoring — installs on a fresh Ubuntu 24.04 server with one command. It's open-source software built on open standards.
$ git clone <your Lumen repository> lumen
$ cd lumen
$ sudo bash install.sh
# Checks the server, asks for your domain and email,
# installs Docker, issues TLS certificates, starts every
# service, verifies them, schedules encrypted backups and
# prints your URLs and next steps (never your secrets).Questions people ask
Can Lumen staff read my messages?
Not in encrypted rooms, which is every room by default. Messages and files are encrypted on your devices with keys that never reach our servers. We can see metadata such as who is in a room and when messages are sent.
Is it post-quantum secure?
Not yet for message content, and we won't claim otherwise. Matrix's Olm/Megolm encryption uses classical cryptography (X25519, Ed25519, AES-256). Connections to our servers use a hybrid post-quantum key exchange (X25519MLKEM768) when your browser supports it. Our security page explains exactly what that does and doesn't protect.
What happens if I lose my phone?
Sign in on another device and unlock your history with your recovery key, or verify the new device from another one you still have. Without either, old encrypted messages can't be recovered — by design, not even by us.
Can I use other Matrix apps?
Yes. Lumen speaks standard Matrix, so apps such as Element can sign in to your account, and you can talk to people on other Matrix servers.
What happens to my data if I stop paying?
Nothing is deleted. Your workspace moves to the Free plan's limits after a grace period; your chats and files stay exactly where they are.