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MIT-licensed core, public docs, and self-service project validation.

Personal Home Account Security Redeem Code Order Management Member Terms FAQ Customer Service

Billing

How do I request an invoice?

Send your invoice details to [email protected] with the subject "Invoice Request".

Include the invoice type, company name, tax number, address, and phone number.
Also include the bank name, bank account number, and related order information or payment proof when available.
If you are not sure what to prepare, confirm with customer service first.

Open order management

Support

Which channel should I use for support, orders, or public feedback?

Different channels are better for different kinds of requests.

Use [email protected] for pre-sales consultation, enterprise cooperation, and manual order coordination.
Use the same email for invoices, payment issues, and order follow-up that needs archived materials.
Use GitHub for public product feedback, documentation review, and community-visible questions.

Open customer service

Membership

Do I need to pay before using relation-graph?

No. The MIT-licensed core can be used for commercial projects without opening a paid plan first.

Paid plans mainly reduce trial-and-error time and provide richer examples.
They are also the path to higher-priority human support and clearer delivery coordination.
Choose based on project urgency, delivery pressure, and how much direct support you need.

Review member terms

Account

What should I do if third-party sign-in or account binding fails?

If the issue happens after sign-in, check the Account Security page first. If sign-in itself fails, send enough context for the issue to be reproduced.

Confirm the current binding status of email, Google, or GitHub when the account page is still accessible.
Send the account email, the exact provider involved, and the step where the error appears.
Include screenshots, redirect information, or browser and network details when possible.

Open account security

Membership

What if I already purchased Pro and my company later opens Enterprise?

The current site policy still treats this as a supported handover case.

The personal Pro amount can be returned to you after the company opens Enterprise.
Personal memberships can still request invoices.
For order-level confirmation, contact customer service with the related order information or payment proof.

See policy details

Frequently Asked Questions

How do I request an invoice?

Which channel should I use for support, orders, or public feedback?

Do I need to pay before using relation-graph?

What should I do if third-party sign-in or account binding fails?

What if I already purchased Pro and my company later opens Enterprise?