Terms of Service

Last updated: September 21, 2026.

Sister Software is currently operated by Nirrus LLC, a Delaware limited liability company.

These Terms of Service ("Terms") govern your use of websites, commercial licensing systems, support, evaluations, design-partner programs, and other services operated by Sister Software ("Sister Software", "we", "us").

Mailwoman itself is self-hosted software. Your rights to use the Mailwoman software are governed separately by the applicable software license.

1. Mailwoman software​

Mailwoman is available under separate software licensing terms, including:

• the GNU Affero General Public License v3.0 only (AGPL-3.0-only); and
• commercial licensing terms where applicable.

These Terms do not grant, restrict, replace, or modify rights provided by an applicable software license.

Your rights to install, copy, modify, distribute, embed, or operate Mailwoman are determined by the software license under which you use it.

If these Terms conflict with an applicable software license regarding rights to the software, the software license controls.

The legal entity operating Sister Software's websites and commercial services does not necessarily own all copyrights, trademarks, datasets, models, or other intellectual property associated with Mailwoman. Applicable license documents identify the rights being granted and, where relevant, the party granting them.

2. Self-hosted operation​

Mailwoman is designed to run on infrastructure you control.

Ordinary parsing, geocoding, resolution, and related workload processing occur on your computer, browser, server, or other infrastructure.

Sister Software does not operate Mailwoman as a hosted geocoding service merely because we operate:

• the Mailwoman website;
• documentation;
• software distribution infrastructure;
• commercial license management;
• billing systems;
• support channels; or
• other business services related to Mailwoman.

Your locally processed addresses, coordinates, customer records, query histories, and other workload data are not transferred to us through ordinary Mailwoman operation.

3. Websites and services we operate​

These Terms apply to services operated by Sister Software, which may include:

• mailwoman.ai and related websites;
• documentation and software-distribution services;
• commercial license checkout and management;
• license issuance, refresh, and optional online verification;
• support and communications;
• evaluations and design-partner programs; and
• separately agreed commercial services.

Some browser applications or demonstrations may download Mailwoman software, models, datasets, maps, or other assets from our infrastructure while performing the substantive processing locally.

We also host reference-data bundles for download by the mailwoman data commands. Operating that catalog is a service covered by these Terms. What a bundle's rows permit is decided by the publisher of those rows rather than by these Terms, and Section 9 addresses that.

These Terms reach the services listed in this section. Installing Mailwoman from a package registry and operating it on your own infrastructure engages no service in this list, and no provision of these Terms adds a condition to rights an applicable software license grants you.

Unless we expressly state otherwise, free websites, demonstrations, previews, or experimental services may be changed, suspended, or discontinued without an availability commitment.

4. Commercial licensing​

Commercial licensing allows customers to obtain rights to Mailwoman under terms separate from the AGPL.

Commercial-license rights are governed by the commercial license agreement, checkout terms, order form, or other agreement applicable to that license.

Commercial licensing may be:

• purchased through self-service checkout;
• included in an enterprise agreement;
• included temporarily in a pilot or evaluation;
• granted under OEM or redistribution terms; or
• otherwise negotiated in writing.

No provision of these Terms itself grants a commercial software license.

5. Commercial services​

Sister Software may offer services including:

• technical support;
• implementation and integration;
• data and coverage analysis;
• evaluation and benchmarking;
• model or resolver development;
• technical research and development;
• design-partner engagements;
• enterprise support;
• OEM arrangements; and
• other technical or commercial work.

Published pricing applies where stated.

Custom work may instead be governed by an order form, statement of work, commercial license agreement, evaluation agreement, or similar written agreement.

If a separate written agreement conflicts with these Terms regarding that engagement, the separate agreement controls.

6. Design-partner, pilot, and evaluation programs​

We may offer prospective or existing customers access to Mailwoman through a pilot, proof of concept, evaluation, or design-partner program.

These programs may be offered at a reduced fee or no fee.

A reduced or waived pilot fee does not establish the price of later commercial use.

The applicable written offer may define:

• pilot duration;
• participating organisation;
• permitted users;
• geographic or operational scope;
• software-license rights;
• support provided;
• evaluation criteria;
• customer data to be provided;
• confidentiality requirements; and
• pricing, if any.

Unless we agree otherwise in writing:

• participation creates no obligation to purchase a later service;
• Sister Software has no obligation to continue providing the pilot after its stated term;
• experimental functionality may change;
• no service-level agreement applies;
• either party may discontinue participation; and
• continued commercial use after the pilot requires an applicable software license or other agreement.

A free pilot does not automatically convert into a paid subscription.

7. Your data​

You retain your rights in information and data you provide to Sister Software.

Ordinary Mailwoman workload data processed entirely on your infrastructure is not provided to Sister Software and is outside the scope of our services.

If you intentionally provide data to us for support, evaluation, benchmarking, model development, integration, or other commercial work, you grant us the limited rights reasonably necessary to perform that work.

We do not acquire ownership of your:

• customer records;
• address lists;
• subscriber information;
• network information;
• coverage data;
• operational data;
• proprietary datasets; or
• other business information

merely because it is supplied to us for an engagement.

Additional confidentiality, security, deletion, retention, or data-processing obligations may be stated in a separate agreement.

Our handling of personal information is also governed by our Privacy Policy.

8. Results and outputs​

Subject to applicable third-party rights, you may use results generated from your own inputs by Mailwoman.

Sister Software does not claim ownership merely because Mailwoman produced an:

• address interpretation;
• coordinate;
• match;
• classification;
• confidence value;
• derived geographic fact;
• report; or
• other factual result.

Some results may depend on third-party datasets, models, or other materials.

Those materials may carry copyright, attribution, database-right, share-alike, or other obligations independent of the Mailwoman software license.

A Mailwoman commercial license does not grant rights that belong to third parties.

9. Third-party software and data​

Mailwoman incorporates or interoperates with software, models, datasets, and services supplied by third parties.

Third-party materials remain subject to their respective licenses and terms.

Sister Software cannot waive or grant rights belonging to a third party.

Before redistributing data, models, or derived datasets, you are responsible for reviewing the applicable third-party notices and provenance information.

That responsibility covers what you do with the material. It does not shift to you the permissions Sister Software needs for its own acquisition, preparation, hosting, and distribution of the material we publish. Those remain ours.

Optional datasets​

Reference-data bundles are separate materials. Each one is rows a third party published, and its original license, notices, and conditions govern that material. Neither a Mailwoman software license nor a commercial license waives them, and the publishers of those rows are not licensors of anything Sister Software offers.

Choosing at runtime which bundles to download is your decision about your installation. It is a separate question from the permissions we need to prepackage, host, and distribute a bundle, and your choice neither grants nor limits those.

mailwoman data --list and mailwoman data pull print each bundle's publishers, terms, conditions, and open questions before any transfer begins.

Pretrained artifacts​

A pretrained package's inputs are fixed when the model is trained, including inputs inherited from a base package whose model graph a data-only overlay decodes through. Installing a package without downloading any reference-data bundle does not change that lineage and does not remove a notice attached to it.

Each published @mailwoman/neural-weights-* package carries a PROVENANCE.json recording, per artifact, what we hold about its inputs and which questions we have not answered. It records gaps as gaps: a package whose model card names no training sources reads as recording none, which is a different statement from having none. No artifact is recorded there as cleared for any particular use, and a generated notice explains what we hold rather than granting a right we lack.

10. Confidential information​

During a commercial, support, pilot, or design-partner engagement, either party may receive non-public technical, commercial, operational, or business information from the other.

Each party will use reasonable care to guard information that:

• is identified as confidential; or
• a reasonable person would understand to be confidential given its nature and the circumstances of disclosure.

Confidential information may be used only for the purpose for which it was disclosed.

This obligation does not apply to information that:

• becomes public without breach of an obligation;
• was already lawfully known to the receiving party;
• is independently developed without use of the confidential information;
• is lawfully obtained from another source without confidentiality obligations; or
• must be disclosed by law.

A separate agreement may impose different or additional confidentiality terms.

11. Feedback​

You may provide suggestions, bug reports, feature requests, benchmark results, or other feedback about Mailwoman.

You allow us to use that feedback to improve Mailwoman and related products and services without restriction or payment.

This permission does not transfer ownership of:

• your customer data;
• confidential information;
• proprietary datasets;
• source code provided under separate terms; or
• other intellectual property that is not reasonably considered feedback.

Intellectual-property terms for specifically commissioned work may be addressed separately.

12. Acceptable use of services we operate​

You may not use infrastructure or services operated by Sister Software to:

• violate applicable law;
• gain unauthorised access to systems or data;
• bypass access controls;
• intentionally disrupt our infrastructure or other users;
• distribute malicious code through our systems; or
• use our systems to carry out or assist fraud or abuse.

This section applies only to systems operated by Sister Software.

It does not impose additional restrictions on independently granted open-source rights to Mailwoman software.

13. Fees, billing, and taxes​

Fees are stated on the applicable:

• pricing page;
• checkout;
• order form;
• statement of work;
• commercial license agreement; or
• other written offer.

Unless stated otherwise, prices exclude applicable VAT, sales tax, and similar taxes.

Recurring subscriptions continue according to the billing terms accepted when purchased.

Promotional pricing, credits, discounts, pilots, and design-partner pricing apply only for their stated scope and duration.

A reduced or waived fee does not obligate Sister Software to offer the same terms for future service.

14. Availability and support​

Unless expressly agreed otherwise in writing, these Terms do not create:

• an uptime guarantee;
• service-level agreement;
• support-response commitment;
• maintenance schedule;
• data-refresh schedule;
• compatibility guarantee;
• acceptance threshold; or
• continuing obligation to develop any particular feature.

Enterprise or other negotiated agreements may establish such commitments separately.

15. No warranty​

Except where expressly agreed otherwise in writing, services operated by Sister Software are provided "as is" and "as available."

Mailwoman software is subject to the warranty terms of the software license under which you use it.

To the maximum extent permitted by law, Sister Software disclaims implied warranties relating to services covered by these Terms, including warranties of merchantability, fitness for a particular purpose, and non-infringement.

Geocoding, address interpretation, geographic inference, and source datasets may contain errors, omissions, outdated information, or ambiguity.

Mailwoman results should not be treated as authoritative where an incorrect result could create material safety, legal, financial, or other consequences without appropriate independent verification.

16. Limitation of liability​

To the maximum extent permitted by law, Nirrus LLC, Sister Software, and persons providing the covered services will not be liable for indirect, incidental, special, consequential, exemplary, or punitive damages arising from these Terms or services operated by Sister Software.

This includes loss of:

• profits;
• revenue;
• business opportunities;
• goodwill; or
• data.

Except for liability that cannot legally be limited, aggregate liability arising from a paid service covered by these Terms will not exceed the amount paid for that service during the twelve months immediately preceding the event giving rise to the claim.

For services provided without charge, aggregate liability will not exceed US$100.

A separate written agreement may establish different liability terms.

No provision of this section changes liability rules established by an applicable open-source license for software obtained independently under that license.

17. Suspension and termination​

You may stop using services covered by these Terms at any time, subject to any separate agreement.

We may suspend or terminate access to infrastructure we operate if you:

• materially breach these Terms;
• fail to pay amounts due;
• create a material security risk;
• use the service unlawfully; or
• interfere with operation of the service.

Termination of these Terms does not revoke rights previously and independently granted to you under an open-source license.

Commercial software-license termination is governed by the applicable commercial license agreement.

18. Changes to these Terms​

We may update these Terms as our services, business structure, providers, or legal obligations change.

Changes apply prospectively from the date the revised Terms are published.

A change to these Terms does not retroactively alter:

• an open-source software license;
• an executed commercial license agreement;
• an order form;
• a statement of work; or
• another agreement that establishes its own terms.

19. Changes to the operating entity​

Sister Software is currently operated by Nirrus LLC.

Responsibility for websites, commercial services, interfaces, or other business operations associated with Sister Software may later move to another legal entity.

If that occurs, these Terms and the Privacy Policy will be updated to identify the responsible entity, and any notice or consent required by applicable law or an existing agreement will be provided.

A change in the entity operating Sister Software's services does not by itself transfer ownership of Mailwoman intellectual property or alter software-license rights previously granted.

Nirrus LLC may assign agreements relating to the services covered by these Terms to a successor or affiliated entity as part of a merger, reorganisation, financing, sale, or transfer of the relevant business, subject to applicable law and any separate contractual restrictions.

20. Governing law​

Unless a separate written agreement states otherwise, these Terms and services operated by Nirrus LLC are governed by the laws of the State of Delaware, United States, without regard to conflict-of-law principles.

This provision applies to these Terms as terms of services operated by Nirrus LLC.

It does not determine ownership of Mailwoman intellectual property, modify an open-source license, or override governing-law provisions contained in a separate software license or commercial agreement.

21. Entire agreement​

These Terms, together with any policies or documents expressly incorporated into them, form the agreement governing the services to which they apply.

Separate software licenses, commercial license agreements, order forms, statements of work, and other written agreements remain independently effective according to their terms.

22. Contact​

Questions about these Terms, commercial licensing, design-partner programs, or other services may be sent to:

Sister Software currently operated by Nirrus LLC, a Delaware limited liability company

support [at] sister [dot] software