Guide · Self-hosting

Updated August 9, 2026 · Simply Finance

Run your own encrypted sync relay on Cloudflare.

The built-in relay works without setup. Self-host only if you want the encrypted relay to run inside your own Cloudflare account and you are willing to maintain its usage and security settings.

Before you begin

You need a Cloudflare account and a GitHub or GitLab account. Cloudflare uses the Git account to create your own copy of the relay. You do not need to install anything or own a domain.

The generated URL is enough

Cloudflare gives the relay a public HTTPS address ending in workers.dev. Use that address directly in Simply Finance.

Ask an AI agent to do it

Open the SimplySync Relay repository in ChatGPT/Codex or Claude Code and say:

Host my own SimplySync relay.

The agent handles local tooling, Cloudflare authentication, storage, migrations, deployment, and health verification. It pauses only when you must enter login, MFA, CAPTCHA, billing details, or accept terms directly in Cloudflare.

Deploy the relay

Deploy my relay
Step 1

Sign in

Select the button, sign in to Cloudflare, and connect GitHub or GitLab when prompted.

Step 2

Keep the defaults

Cloudflare shows the Worker, database, and bucket names. The suggested values are ready to use.

Step 3

Deploy

Select Deploy and wait while Cloudflare creates the relay and applies its database migrations.

Step 4

Copy the address

Copy the HTTPS address ending in workers.dev from the successful deployment screen.

Connect Simply Finance

  1. Open Settings, then Sync Relays.
  2. Add the full workers.dev HTTPS URL from Cloudflare.
  3. Keep the built-in relay enabled while you verify the new relay.
  4. Confirm Connected, then verify a change on a second device.
  5. After verification, keep both relays or choose Custom only.

Why the public URL is safe

The URL is an address, not a decryption key. Simply Finance encrypts data before it leaves the device, and the recovery phrase never goes to the relay. Knowing the URL does not expose balances, transactions, budgets, or notes.

  • Each owner uses a private, recovery-phrase-derived write capability.
  • The relay limits requests, new owners, writes, and stored bytes.
  • Oversized or unauthenticated requests are rejected early.
  • A custom domain and extra WAF rules are optional, not required.
Optional notification

If you want usage alerts, enable Workers, D1, and R2 notifications in Cloudflare. This is maintenance visibility, not a step required to make the relay work.

FAQ

Do I need to know how to code?

No. The recommended setup happens in your browser. Cloudflare creates and connects the Worker, D1 database, and R2 bucket for you.

Can the relay read my finances?

No. Simply Finance encrypts sync data on the device. The relay stores encrypted events and blobs, but it does not receive the key required to read them.

What does Cloudflare cost?

Pricing and included usage can change. Review the current Workers pricing, D1 pricing, and R2 pricing before deployment, then enable usage and billing notifications.

Can I keep using the built-in relay?

Yes. The built-in relay is the managed default and is intended for ongoing use, not just testing. You can keep it enabled alongside your own relay or choose Custom only. We plan to keep the built-in relay available for as long as capacity allows, but it may be retired later if demand grows beyond what we can sustainably provide.