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Terms of Service

Effective: 1 October 2026

1. Introduction

These Terms of Service (the “Terms”) are a legal agreement between you (“you”, “your”, or “Customer”) and Sizmic Limited, a company registered in England and Wales with company number 15403344 and registered office at 78 James Smith Court, Dartford, England, DA1 5XL (“Sizmic”, “we”, “us”, or “our”). Sizmic operates the Kirak Studio service (“Studio” or the “Service”).

By creating a Studio account, clicking to accept these Terms, or using the Service, you agree to these Terms. If you are entering into these Terms on behalf of a company or other organisation, you represent that you have authority to bind that organisation, and “you” refers to that organisation.

If you do not agree to these Terms, do not use the Service.

The open-source runtime is separate. The Kirak backend runtime is open-source software licensed under the Apache License 2.0. Your use of the runtime on your own infrastructure is governed by that licence, not by these Terms. These Terms apply only to the hosted Kirak Studio service.

2. Definitions

  • “Account” — your registered Studio account.
  • “Customer Content” — everything you or your Users upload to, create in, or generate through the Service, including your models.json and kirak.json declarations, hooks, custom endpoints, source code, configuration, databases, files, and the data your Applications process.
  • “Application” — a backend you build, deploy, and operate using the Service.
  • “Users” — the individuals you authorise to access your Account (for example, teammates).
  • “End Users” — the people who interact with your Applications.
  • “Instance” — a dedicated virtual private server or other compute resource provisioned to run your Application.
  • “AI Build Agent” — the AI-assisted feature that helps generate declarations, hooks, and endpoints, further described in the AI Build Agent Terms.
  • “Plan” — the subscription tier you select (currently Free, Hobby, Pro, or Agency), including any usage limits described at kirak.io.
  • “Documentation” — the user guides and technical documentation we make available for the Service.

3. Eligibility and Accounts

3.1 Age. You must be at least 16 years old to use the Service. If you are under 18, you may only use the Service with the involvement of a parent or guardian, and that parent or guardian is responsible for your use.

3.2 Registration. You must provide accurate and complete information when you register and keep it up to date. One person or legal entity may not maintain more than one free Account, and Accounts may not be shared, sold, or transferred without our consent.

3.3 Account security. You are responsible for all activity that occurs under your Account and for keeping your credentials secure. Notify us at support@kirak.io promptly if you become aware of any unauthorised use.

3.4 Responsible party. You are responsible for your Users’ compliance with these Terms and for all acts and omissions of your Users.

4. The Service

4.1 What Studio provides. Studio is a managed service for building, deploying, operating, and monitoring backends that run on the Kirak runtime. It includes the build and AI assistance features, deployment to dedicated Instances (or, on eligible Plans, to your own cloud account), and the operating console (logs, traces, alerts, data browser, and similar tools), as described in the Documentation. The Studio API and any MCP or other programmatic endpoints we provide are part of the Service. We may set and change rate limits and usage quotas for them, automated access must respect those limits, and we may suspend API access for abuse or excessive use independently of your Account.

4.2 Changes to the Service. We may add, change, or remove features. We will not make a material reduction to the core functionality of a paid Plan during a paid Subscription Term without giving you a reasonable opportunity to terminate and receive a pro-rata refund of prepaid, unused fees.

4.3 Service levels. The Pro, Agency, and Enterprise plans are covered by the Service Level Agreement at kirak.io/legal/sla, which forms part of these Terms. The Free and Hobby plans are provided “as is” with no service level commitment.

4.4 Beta and preview features. From time to time we make features available that are labelled “beta”, “preview”, “experimental”, “early access”, or “coming soon” (“Beta Features”). Beta Features are provided as is and as available, for evaluation, and:

  • may be changed, suspended, or withdrawn at any time, in whole or in part;
  • are not covered by the Service Level Agreement or any support commitment;
  • may be subject to additional terms we present when you enable them; and
  • may contain defects and may lose data, and should not be used for anything you cannot afford to lose or recreate.

If you give us feedback on a Beta Feature, Section 11.2 applies. To the fullest extent permitted by law, we are not liable for any loss arising from your use of a Beta Feature.

4.5 Support. We provide support for the Service through the channels described at kirak.io/support, which also describes the target first-response times for each Plan. Those targets are operational goals, not contractual commitments, and we may change them. Support covers the operation of the Service itself; it does not include writing, reviewing, or debugging your application code, hooks, or configuration.

4.6 Third-party services. The Service integrates with third-party providers (for example, payment processors, email and SMS providers, object storage, and AI model providers). Your use of those integrations may be subject to the third party’s own terms, and we are not responsible for third-party services.

5. Customer Content and Your Applications

5.1 Ownership. As between you and us, you own all Customer Content and your Applications. We do not claim ownership of them.

5.2 Licence to us. You grant us a worldwide, non-exclusive licence to host, copy, transmit, display, and process Customer Content solely to provide, secure, and support the Service, to prevent or address technical or security problems, and to comply with law. This licence ends when the Customer Content is deleted from our active systems, except for residual copies in encrypted backups (purged within 30 days) and anonymised or aggregated data.

5.3 Your responsibility for Customer Content. You are solely responsible for Customer Content and your Applications, including their legality, accuracy, and security, and for having all rights and consents needed for us to process Customer Content as described in these Terms. We do not review or moderate Customer Content and are not responsible for it.

5.4 End Users. You are responsible for your Applications’ relationship with your End Users, including providing them with any required notices, obtaining any required consents, and handling their requests. We have no direct relationship with your End Users.

5.5 Data protection. Where we process personal data on your behalf in providing the Service, that processing is governed by our Data Processing Addendum at kirak.io/legal/dpa, which forms part of these Terms. You are the controller and we are the processor with respect to that personal data.

5.6 Regulated data. The Service is not HIPAA-eligible. You must not use it to store or process Protected Health Information as defined by the US Health Insurance Portability and Accountability Act, and we do not enter into Business Associate Agreements. You must not use the Service in a way that places us in scope for PCI DSS beyond redirecting payments to a compliant payment processor. You may only process special category personal data where you have configured the Service appropriately and have a lawful basis to do so. See the Acceptable Use Policy.

5.7 Backups. We take operational backups of the platform, but you are responsible for maintaining your own backups of Customer Content. We are not liable for any loss or corruption of Customer Content except to the extent directly caused by our failure to meet our security obligations.

6. Acceptable Use

Your use of the Service must comply with our Acceptable Use Policy at kirak.io/legal/acceptable-use, which forms part of these Terms. Among other things, you must not use the Service to host or run anything illegal, malicious, deceptive, infringing, or abusive, and you must not attempt to gain unauthorised access to the Service or interfere with its operation or other customers.

We may investigate suspected violations. If we reasonably believe a violation creates a risk to the Service, to us, or to others, we may suspend or restrict the affected Application or Account as described in Section 10.

7. AI Build Agent

Your use of the AI Build Agent is additionally governed by the AI Build Agent Terms at kirak.io/legal/ai-terms, which form part of these Terms. In summary:

  • You own the declarations, hooks, and endpoints the AI Build Agent generates for you.
  • AI output may be incorrect, incomplete, or insecure. You are responsible for reviewing and testing it before relying on it, especially in production.
  • We do not use your prompts or Customer Content to train third-party foundation models.
  • AI model providers act as our sub-processors and are listed on our Subprocessor List.

8. Fees, Billing, and Taxes

8.1 Plans and charges. Paid Plans and Instance charges are billed in US dollars at the prices shown at kirak.io at the time of purchase. Subscription fees are billed in advance for the billing period you select. Instance usage may be billed by the hour, capped at the stated monthly rate for that Instance size; stopping an Instance stops its usage billing.

8.2 Payment. You authorise us and our payment processor to charge your payment method for all amounts due. If a charge fails, we may retry and may suspend paid features until payment is made.

8.3 Auto-renewal. Paid subscriptions renew automatically for successive periods equal to the prior period unless you cancel before the renewal date. You can cancel at any time in your Account; cancellation takes effect at the end of the current period.

8.4 Changes to pricing. We may change prices. For a change to an existing paid subscription, we will give at least 30 days’ notice before the change applies to your next renewal.

8.5 Upgrades and downgrades. Upgrades take effect immediately and are charged pro rata. Downgrades take effect at the end of the current billing period.

8.6 Taxes. Prices are exclusive of taxes. You are responsible for all applicable sales, use, VAT, GST, and similar taxes, which we may add to your invoice based on your location. If you are required by law to withhold any tax, you must gross up the payment so that we receive the full amount invoiced.

8.7 Refunds. Except where required by law or expressly stated in these Terms, fees are non-refundable and there are no refunds or credits for partial periods, unused Instances, or unused features. Nothing in this section affects your statutory rights as a consumer, where they apply (see Section 8.9).

8.8 Free Plan. The Free Plan and any free trials are provided at no charge and as is. We may change, limit, or discontinue the Free Plan at any time. We may suspend or delete Free Plan Accounts and their Customer Content after a period of inactivity, with notice to the Account email where reasonably practicable.

8.9 Consumers’ right to cancel. If you are a consumer in the United Kingdom (an individual acting for purposes wholly or mainly outside your trade, business, craft, or profession), you normally have the right to cancel a paid subscription within 14 days of purchase under the Consumer Contracts (Information, Cancellation and Additional Charges) Regulations 2013. Because the Service starts as soon as you subscribe, at checkout we ask you to expressly request that it starts during the cancellation period. If you make that request and then cancel within the 14 days, we will refund what you paid, less a proportionate amount for the Service provided up to the time you told us you were cancelling. To cancel, email support@kirak.io or use the cancellation option in your Account within the 14-day period. This section does not apply to business customers.

9. Bring Your Own Cloud (BYOC)

If your Plan allows you to run Instances in your own cloud account:

  • You are responsible for your cloud account, its configuration, its security, and all charges your cloud provider bills you.
  • You grant us the access we need to deploy and operate the Service in your cloud account, and you are responsible for maintaining that access.
  • The service level and support commitments that depend on our infrastructure do not apply to Instances running in your cloud account, except as expressly stated.

10. Suspension and Termination

10.1 By you. You may stop using the Service and close your Account at any time.

10.2 By us. We may suspend or terminate your Account or a specific Application, on notice where practicable, if: (a) you materially breach these Terms (including the Acceptable Use Policy) and do not cure the breach within 10 days of notice, where the breach is curable; (b) you fail to pay amounts due and do not cure within 10 days of notice; (c) we reasonably believe your use poses a security, legal, or operational risk to the Service, to us, or to others, in which case we may act immediately and limit the suspension to what is reasonably necessary; or (d) we are required to do so by law.

10.3 Effect of termination. On termination, your right to use the Service ends. For a period of 30 days after termination (except where we terminate for cause under 10.2(c) or are legally prohibited), you may request an export of your Customer Content in a commonly used format, or retrieve it yourself where the Service allows. After that period, we delete Customer Content from our active systems; residual copies in encrypted backups are purged within a further 30 days, after which the Customer Content cannot be recovered. Sections that by their nature should survive termination (including Sections 5.1, 8, 11, 12, 13, 14, and 17) survive.

10.4 No liability for lawful suspension or termination. We are not liable to you or any third party for any suspension or termination made in accordance with these Terms.

11. Intellectual Property

11.1 Our property. We and our licensors own the Service, the Studio software, the Documentation, and all related intellectual property, other than the open-source runtime (which is licensed under Apache 2.0) and Customer Content. We grant you a limited, non-exclusive, non-transferable, revocable right to access and use the Service during your subscription, subject to these Terms.

11.2 Feedback. If you give us feedback or suggestions about the Service, you grant us a perpetual, irrevocable, royalty-free licence to use it without restriction or obligation to you.

11.3 Trademarks. “Kirak”, “Kirak Studio”, “Sizmic”, and related names and logos are our trademarks. Your use of them is governed by our Trademark & Brand Policy at kirak.io/legal/trademark. These Terms do not grant you any trademark rights.

12. Warranties and Disclaimers

12.1 Mutual. Each party warrants that it has the authority to enter into these Terms.

12.2 Service disclaimer. Except as expressly stated in these Terms or a written service level agreement, the Service, the AI Build Agent, and all Documentation and output are provided “as is” and “as available”, without warranties of any kind, whether express, implied, or statutory, including any implied warranties of merchantability, satisfactory quality, fitness for a particular purpose, non-infringement, and any warranties arising from course of dealing or usage of trade. We do not warrant that the Service will be uninterrupted, error-free, or secure, that defects will be corrected, or that any Application you build with the Service is itself correct, complete, secure, or compliant with any law. To the extent any warranty cannot be excluded as a matter of law, it is limited to the minimum period and extent permitted by that law.

12.3 No professional advice. The Service and any AI output do not constitute legal, security, compliance, or other professional advice.

13. Indemnification

You will defend, indemnify, and hold harmless Sizmic and its officers, employees, and agents from and against any third-party claim, and any resulting losses, damages, liabilities, costs, and reasonable legal fees, arising out of or relating to: (a) Customer Content or your Applications; (b) your or your Users’ use of the Service in breach of these Terms or applicable law; or (c) your infringement or misappropriation of any third party’s intellectual property or other rights.

14. Limitation of Liability

14.1 Exclusion of certain damages. To the fullest extent permitted by law, neither party will be liable for any indirect, incidental, special, consequential, exemplary, or punitive damages, or for any loss of profits, revenue, goodwill, or anticipated savings, or for any loss or corruption of data, in each case arising out of or relating to these Terms or the Service, whether in contract, tort (including negligence), or otherwise, even if advised of the possibility of such damages.

14.2 Cap. To the fullest extent permitted by law, each party’s total aggregate liability arising out of or relating to these Terms and the Service will not exceed the greater of (a) the total fees you paid or owed to us for the Service in the 12 months before the event giving rise to the liability, or (b) US$100.

14.3 Exceptions. Nothing in these Terms excludes or limits either party’s liability for: (a) death or personal injury caused by its negligence; (b) fraud or fraudulent misrepresentation; (c) your payment obligations under Section 8; (d) your indemnification obligations under Section 13; or (e) any other liability that cannot be excluded or limited under the law of England and Wales.

14.4 Basis of the bargain. The parties agree that the limitations in this Section are a fundamental basis of the bargain and apply even if a limited remedy fails of its essential purpose.

15. Confidentiality

Each party may receive non-public information of the other that is marked or should reasonably be understood to be confidential (“Confidential Information”). The receiving party will use Confidential Information only to perform under these Terms and will protect it with at least reasonable care. This does not apply to information that is or becomes public through no fault of the receiving party, was already known to it, is independently developed, or is rightfully received from a third party. Either party may disclose Confidential Information if required by law, giving the other reasonable notice where lawful.

16. Changes to these Terms

We may update these Terms. If we make a material change, we will give notice by email to your Account address or by a notice in the Service at least 15 days before the change takes effect, unless the change is required by law or relates to a new feature, in which case it may take effect sooner. Your continued use of the Service after a change takes effect means you accept the updated Terms. If you do not accept them, you must stop using the Service before the change takes effect.

17. Publicity

We may identify you as a customer of Kirak Studio, including by using your name and logo, on our website and in marketing materials. If you do not want us to, email legal@kirak.io and we will stop within a reasonable time. This does not permit either party to imply any endorsement or partnership that does not exist.

18. General

18.1 Governing law. These Terms and any dispute arising out of or relating to them or the Service are governed by the law of England and Wales.

18.2 Jurisdiction. The courts of England and Wales have exclusive jurisdiction, except that we may bring proceedings for unpaid fees or for infringement of our intellectual property in any court of competent jurisdiction.

18.3 Assignment. You may not assign these Terms without our prior written consent. We may assign these Terms to an affiliate or in connection with a merger, acquisition, or sale of assets, on notice to you.

18.4 Entire agreement. These Terms, together with the Acceptable Use Policy, AI Build Agent Terms, Data Processing Addendum, and any order or plan details, are the entire agreement between the parties about the Service and supersede all prior discussions and agreements. In the event of a conflict, the order of precedence is: (1) a signed written agreement between the parties, if any; (2) the Data Processing Addendum; (3) these Terms; (4) the other policies referenced above.

18.5 Severability and waiver. If any provision is unenforceable, it will be modified to the minimum extent necessary and the rest remains in effect. A failure to enforce a provision is not a waiver.

18.6 Force majeure. Neither party is liable for any delay or failure to perform (other than payment obligations) caused by events beyond its reasonable control.

18.7 Notices. Notices to us must be sent to legal@kirak.io. Notices to you may be sent to your Account email or posted in the Service.

18.8 Third-party rights. A person who is not a party to these Terms has no rights under the Contracts (Rights of Third Parties) Act 1999 to enforce any of its terms.

18.9 Relationship. The parties are independent contractors. These Terms do not create any partnership, joint venture, agency, or employment relationship.

19. Contact

Questions about these Terms: legal@kirak.io
Support: support@kirak.io
Sizmic Limited, 78 James Smith Court, Dartford, England, DA1 5XL, company number 15403344.

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