Document · Licensing · 6 min read

Activate a license on a device

A Kaptain license belongs to a CHYNJ account (your email). "Activating" a device means binding that machine to the license so Kaptain runs in Pro. You can do it two ways — sign in with your CHYNJ account, or paste the license key — and you can see and manage every connected device from your account.

How licensing works

Three facts make the rest of this page simple:

• A license is attached to your CHYNJ account email. Whether you bought it at checkout or an admin issued it to you, it is tied to the email on your account.
• A device is "connected" when its fingerprint is registered against the license. Kaptain does this for you when you activate — you do not manage fingerprints by hand.
• Your account is the source of truth. Your license key and the list of connected devices always live at chynj.ca/account, even if an email never arrives.

Step 1 — Find your license

When a license is issued to you (by purchase or by an admin), CHYNJ emails the key and these same steps. If that email hasn't arrived, don't wait on it — get the key directly:

1. Go to chynj.ca/account and sign in with your CHYNJ account.
2. Under License, your Key is shown as KAPTAIN-XXXXXXXX-XXXX-XXXX with a Copy button.

If you don't have an account yet, create one at chynj.ca/account using the same email the license was issued to, then the license appears automatically.

Step 2 — Install Kaptain on the device

Install the runtime on the machine you want to use, then start it. Full steps are in the Setup Guide. In short:

curl -sL https://chynj.ca/install.sh | sh   # Linux / macOS
kaptain

Kaptain opens its setup wizard at http://localhost:8888. Activation happens during that wizard (and can be redone later from settings).

Step 3, Option A — Activate by signing in (recommended)

This is the "connect my device to my CHYNJ account" path. You don't copy any key.

1. In the Kaptain setup wizard, on the Account step, choose Sign in with your CHYNJ account and use the email + password for the account the license is on.
2. Kaptain checks your account with license.chynj.ca, finds the license attached to your email, and applies it.
3. This machine is registered to the license automatically and shows up under Devices in your account.

Use this path when the person at the device knows the account login. It keeps every device tied to one account with nothing to paste.

Step 3, Option B — Activate by license key

Use this when you only have the key (for example, you forwarded the key to a teammate's machine).

1. In the setup wizard, go to the License step.
2. Click "Already have a license key? Enter it here."
3. Paste your key (KAPTAIN-XXXXXXXX-XXXX-XXXX) and click Activate & Continue.

Kaptain validates the key with license.chynj.ca and registers this device against it. The result is identical to Option A — the device is now connected to the license.

Restoring access after a trial (incl. a remote machine)

Common situation: a machine ran the free trial, the trial ended, and you've since issued or bought a license — but that machine still shows "Trial expired." A trial is tied to the machine, not to your CHYNJ account, so the machine doesn't yet know about the new license. You restore it the same way you activate — and you do not need to reinstall.

The license and sign-in screens stay reachable even when a trial has expired, so you're never locked out of recovery. On that machine:

• Best — sign in with your CHYNJ account. This links the machine to your account. From then on it re-checks your account every few hours and applies whatever license is on it — so this and any future renewal activate automatically, with nothing else to do.
• Or paste the license key on the "Trial expired" screen and activate.

If the machine is somewhere else (you're remote)

You need to reach that machine's Kaptain screen once:

• If you enabled Tailscale during setup, open http://<that-machine's-tailscale-address>:8888 from anywhere and sign in / enter the key.
• Otherwise use SSH or remote desktop to that machine and open http://localhost:8888 there.

Why account sign-in is the durable fix: once a machine is signed into your CHYNJ account, licensing becomes automatic and remote. Issue, renew, or move a license on your account and every signed-in machine reflects it within a few hours (or immediately on restart) — you won't have to touch the machine again.

Devices & limits

Each license allows a fixed number of connected devices:

• Pro — up to 5 devices.
• Admin — up to 10 devices.

Activating a 6th device on a Pro license (or 11th on Admin) is refused until you free a slot. Device binding uses a hashed machine fingerprint — Kaptain never sends the raw fingerprint, only its SHA-256.

Manage / disconnect devices

From chynj.ca/account, the Devices list shows every machine using your license, with its nickname and last-seen date.

• To free a slot or remove a machine you no longer use, click Sign out next to that device. Kaptain on that machine stops running Pro until it is re-activated; your account and other devices are unaffected.
• Re-activating a previously removed device is fine — just run Option A or B again on it.

Validation & offline use

After activation, Kaptain re-checks the license with license.chynj.ca on startup and roughly every 4 hours. If the machine is temporarily offline, Kaptain falls back to a signed local cache so work continues; it re-validates as soon as it's back online. You do not need to re-enter anything.

Troubleshooting

• No license email arrived. You don't need it — sign in at chynj.ca/account and copy the key from the License card, or just use Option A (sign in inside Kaptain). Also check spam for mail from noreplycode@chynj.ca.
• "No license found for this account." The license must be on the same email you signed in with. Confirm the email on chynj.ca/account matches where the license was issued.
• "Device limit reached." Open chynj.ca/account → Devices and sign out a machine you no longer use, then activate again.
• "Invalid license key." Re-copy the key from your account (use the Copy button) to avoid stray spaces, and make sure it has the form KAPTAIN-XXXXXXXX-XXXX-XXXX.
• Need to move a license to a new machine. Activate on the new machine, then sign the old one out from chynj.ca/account → Devices.

Still stuck? Email hello@chynj.ca.