Terms of Service

Effective 28 August 2026. These terms govern the hosted Sendsprite service at sendsprite.com (the "Service"), operated by defy.works ("we", "us"). By creating an account or using the Service you agree to them. If you are accepting on behalf of a company, you confirm you have authority to bind it, and "you" means that company.

The Service is a control plane for transactional and marketing email: an API, a dashboard, domain provisioning, an event pipeline, webhooks, an SMTP relay, and the sendsprite SDK, CLI and MCP server. Delivery itself happens through your own Amazon SES account, which you connect to the Service and which remains governed by your agreement with Amazon Web Services.

1. Self-hosted instances are not covered

Sendsprite is open source, and anyone may run their own instance. These terms apply only to the instance we operate at sendsprite.com. An instance run by someone else — including one you run yourself — is governed by whoever operates it, and by the software licence in the repository, not by this document.

2. Accounts and teams

You need an account to use the Service. You may sign up with an email address and password, or through Google or GitHub. Keep your credentials, API keys and SMTP passwords confidential; everything done with them is treated as done by you. Tell us at hello@defy.works as soon as you suspect they have been compromised.

Every resource — domains, keys, contacts, templates, emails — belongs to a team. Team owners and admins can invite members, change settings, connect or disconnect AWS, and delete the team. Actions of every member are attributed to the team.

You must be at least 18 years old, or the age of majority where you live, to use the Service.

3. Acceptable use

The Service sends email on your behalf, and the reputation of every sender depends on every other sender behaving. You agree that you will:

• Send only to people who have agreed to hear from you. Purchased, scraped or rented lists are prohibited. Marketing email must have consent you can demonstrate.
• Keep the unsubscribe mechanism intact. Campaign messages carry an unsubscribe link and RFC 8058 one-click headers; you may not remove, hide or break them, and you must honour every unsubscribe and suppression.
• Identify yourself truthfully. No forged headers, misleading subject lines, impersonation of another person or organisation, or sending from domains you do not control.
• Comply with the law where you and your recipients are, including anti-spam, consumer protection and data protection laws (for example CAN-SPAM, GDPR, and Korea's Personal Information Protection Act and Act on Promotion of Information and Communications Network Utilization).
• Not send malware, phishing, fraud, harassment, illegal content, or content that infringes others' rights.
• Not probe, overload or circumvent the Service, its rate limits, its billing, or the accounts of other teams.

We may suspend sending, ban a team, or terminate an account, with or without notice, where we reasonably believe these rules are being broken or where Amazon, a mailbox provider or a regulator requires it. We will tell you why unless the law prevents us.

4. Your content

You own the emails, templates, contacts and other content you put into the Service. You grant us the limited licence needed to store, process, render and transmit it in order to provide the Service, and for nothing else. You are responsible for that content, for having the rights to send it, and for the consequences of sending it.

We do not read your email content except where necessary to operate the Service (for example to debug a delivery failure you have reported), to respond to an abuse complaint, or where the law requires it.

5. Your Amazon Web Services account

Sending requires you to connect an AWS account, either through the CloudFormation quick-create stack or by pasting IAM credentials. You are responsible for that account, for the charges Amazon bills to it, and for keeping the permissions in scope. We store the credentials encrypted, use them only for the SES, SNS and CloudFormation operations the Service performs, and you can disconnect at any time from Settings → Sending. Where the Service cannot tear down a stack it will say so and leave you a console link; you are responsible for cleaning up resources it could not remove.

6. Plans, billing and taxes

The Service offers a Free plan and paid plans with an included monthly volume and a per-1,000 overage rate. Current prices are shown in Settings → Billing. Payments are processed by Polar, acting as merchant of record; Polar is the seller on your invoice and handles VAT and sales tax, and its terms apply to the payment itself.

Subscriptions renew monthly until cancelled. Usage is metered per delivered email and overage is billed in arrears. You can cancel, change plan or update payment details through the customer portal at any time; cancellation takes effect at the end of the current period, and we do not refund partial periods except where the law requires it. If a payment fails we may downgrade the team to the Free plan's limits after a grace period.

We may change prices with at least 30 days' notice by email or in the dashboard. Continued use after the change takes effect means you accept the new price.

7. Availability and support

We aim to keep the Service available and will tell you about planned maintenance where we can, but we do not promise any particular uptime. Support is by email at hello@defy.works and through the GitHub repository; there is no guaranteed response time on the Free plan.

We may change or retire features. Where a change removes something you depend on we will give reasonable notice, and the software remains open source so you can always self-host.

8. Software licences

The Sendsprite server and client packages are licensed under the MIT License. That licence governs the code, not this Service, and nothing here restricts the rights it grants. "Sendsprite" and its logo are trademarks of defy.works; see the trademark policy in the repository.

9. Termination

You can delete your team at any time from Settings → Danger zone, and your account by contacting us. We may terminate or suspend your access under section 3, for non-payment, or on 30 days' notice for any other reason. On termination your right to use the Service ends, and we delete your data as described in the Privacy Policy. Sections 4, 10, 11 and 12 survive termination.

10. Disclaimers

The Service is provided "as is" and "as available". To the fullest extent permitted by law we disclaim all warranties, express or implied, including merchantability, fitness for a particular purpose and non-infringement. In particular we do not warrant that email will be delivered, delivered on time, or land in the inbox: delivery depends on Amazon SES, on mailbox providers and on your own sending reputation, none of which we control.

11. Limitation of liability

To the fullest extent permitted by law, we are not liable for any indirect, incidental, special, consequential or punitive damages, or for lost profits, revenue, data or goodwill, arising out of or related to the Service. Our total liability for all claims in any twelve-month period is limited to the amount you paid us for the Service in that period, or ₩100,000 if you paid nothing. Nothing in these terms limits liability that cannot be limited under applicable law, including for wilful misconduct or gross negligence.

12. Indemnity

You will defend and indemnify us against claims, damages and costs (including reasonable legal fees) arising from your content, your use of the Service in breach of these terms, or your violation of any law or third-party right.

13. Changes to these terms

We may update these terms. For material changes we will give at least 14 days' notice by email or in the dashboard before they take effect. If you do not agree, stop using the Service before the change takes effect; continued use afterwards is acceptance.

14. Governing law and disputes

These terms are governed by the laws of the Republic of Korea, without regard to conflict-of-law rules. Any dispute that we cannot resolve informally will be brought in the courts of Seoul, Republic of Korea, and you and we submit to their jurisdiction. If you are a consumer in a jurisdiction whose law gives you the right to sue at home, nothing here takes that away.

15. General

These terms, the Privacy Policy and any plan-specific terms shown at checkout are the entire agreement between you and us about the Service. If a provision is unenforceable the rest remains in force. You may not assign these terms without our consent; we may assign them in a merger or sale of the business. Failure to enforce a provision is not a waiver.

Questions: hello@defy.works.