Terms of Service

Last Revised: August 2021


Exercism (also referred to as exercism.org) is an online platform designed to help you improve your coding skills through practice and mentorship.

Our platform comprises of a web site is located at https://exercism.org (and associated subdomains) and a command line application (CLI).

Exercism is run and managed by Exercism, a not-profit-company. The following Terms of Service (these Terms) are an agreement between Exercism and you, and govern your permitted use of our Platform.

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Our general approach should be fairly straightforward to understand:

  1. Our core services are provided free of charge on an "as is" basis. We do our best to keep our platform operational, but we cannot offer any guarantees of this.
  2. We aim to have a user-friendly approach to privacy and security.
  3. We will run advertising and/or sponsorship, but we won't sell your data, or use your personal data to target you for marketing purposes.
  4. We want to make Exercism an enjoyable and safe place for everyone and we will take action against users who undermine our Platform and/or our community values.
  5. The content you submit to the Platform such as Programming/Code Solutions, or mentoring Feedback are published openly under an open license.
  6. We will try to be open about how we choose to develop the Platform and how we use the data and content contained within it.

In detail

Exercism is run and managed by Exercism ("We", "Us"), a not-profit-company registered in the UK with Company Number 11733062. The following Terms of Service (these Terms) are an agreement between Exercism and you, and governs your permitted use of our Platform.

Any clause headings, numbers, and/or emphasis in these Terms are for ease of reference only and shall not be taken into account in the construction or interpretation of the clauses to which they refer.

If any provision of these Terms is found to be illegal, void or unenforceable, then that provision shall be deemed severable from these Terms and shall not affect the validity and enforceability of any remaining provisions of these Terms.

We reserve the right to modify these Terms at any time by posting revised Terms on https://exercism.org. These Terms apply to all who access or use our Platform, registered or otherwise.

Any personal information submitted to our Platform is subject to our Privacy Policy.


  • Track(s) - a programming language track on Exercism, a collection of exercises and a group of Mentors who provide feedback on Solutions.
  • Solution(s) - code that is submitted by our Users (posted on Exercism) as a solution to an exercise in a track.
  • Iteration - a particular version, or revision, of an individual's Solution.
  • Feedback - feedback given by a Mentor or other User relating to a Solution that a User has posted on Exercism.
  • Mentor - a User of Exercism who provides Feedback on Solutions. A Mentor belongs to a Track. Individual users may be students on one track and mentors on another.
  • User(s) - any user of the Exercism Platform, whether signed up or not.
  • User Contributed Content - any content that Users post to our Platform.

User obligations

When you access our services, whether registered or not, you become a User of our Platform.

As a User, you are solely responsible for ensuring that:

  • your account registration is complete and remains up to date.
  • your use of our services is consistent with these Terms of Service, our Privacy Policy and our Code of Conduct

When using our Platform, you AGREE NOT TO:

  • share or upload defamatory, libelous, or inaccurate content.
  • share or upload any content that is unlawful.
  • share or upload content that a reasonable person could deem to be objectionable, offensive, distressing, or otherwise inappropriate. We would recommend that you familiarize yourself with our Values and Code of Conduct.
  • impersonate any person or entity, falsely claim an affiliation with any person or entity.
  • access the Platform accounts of others without permission, or perform any other fraudulent activity.
  • make unsolicited offers and advertisements to other Users of the Platform (including, but not limited to, unsolicited advertising and unsolicited job postings).
  • attempt to collect personal information about Users or third parties without their consent.
  • intentionally interfere with our Platform's security-related features.
  • intentionally interfere or damage our Platform, or any user’s enjoyment of it.
  • use the Platform for illegal purposes, or in violation of any local, state, national, or international law, including, without limitation, laws governing intellectual property, data protection, and privacy.

Service Eligibility

We offer our Platform to the widest possible audience. However, the following eligibility restrictions do apply:

Non-Eligibility based on suspension or removal

Our services are not available to any users previously suspended or removed from the Platform. It is expected that such removals will be governed by these Terms of Service and our Code of Conduct.

Eligibility based on age (and region)

You have to be older than a minimum age to have an account on our Platform. This is to keep our users safe.

You must be at least 13 years old to access our Platform. If you are under 13 years old, you may not access our Platform, and may not provide or post any personal information to our Platform (including, for example, your name, age, and contact details).

However, if you are located within the United Kingdom or the European Union, you must be at least 16 years old to access our Platform. If you are under 16 years old, you may not access our Platform, and may not provide or post any personal information to our Platform (including, for example, your name, age, and contact details).

Removal/Suspension/Termination of accounts

Exercism reserves the right to refuse, suspend or terminate - without notice - your access to the Platform if it determines, in its sole discretion, that you have in any way violated these Terms of Service and/or our Code of Conduct.

Content Permissions and Licensing

Content delivered through our Platform may be owned by us (Our Content), contributed by our wider community of volunteers (Community Content), or be contributed by users like You (User Contributed Content). You agree to abide by all copyright notices and restrictions contained in the content you access.

We are committed to Open Source, and as a result, many of the resources on our Platform are licensed under an open source license. You are free to re-use such content subject to that respective license. The following sections provide information about the different classes of content on our Platform.

Our Content

All materials displayed on our Website and/or Platform are Copyright Exercism.

Where a resource does not appear to have a clear licensing statement, we would recommend that you check our GitHub source-code repositories. You should not assume that all content on our Platform is openly licensed, but it generally will be.

Community Content

All of the exercises delivered through the platform have been built by a community of volunteers and are licensed mainly under the MIT License. All of this content is available directly through our GitHub repositories (see https://github.com/exercism) where specific license details can be viewed.

User Contributed Content

The primary purpose of the Platform is to provide a space where individuals can solve programming (coding) challenges, submit them, and receive feedback. Our aim is to help Users develop competence in coding and also to develop skills in giving and receiving feedback.

When you use our Platform, you will be presented with a series of exercises for you to download and solve, and be invited to upload your Solution (potentially as a series of improvements, each named an Iteration) for review.

You agree that all content (User Contributed Content) that you have previously uploaded, or subsequently upload, to the Platform -- including, without limitation, your Solution and Iteration content -- will be licensed to Exercism on worldwide, royalty-free, non-exclusive, perpetual basis. You grant Exercism the perpetual and irrevocable right and license to process, copy, distribute and to commercially exploit all such User Contributed Content that you contribute. You should understand that this right will persist even if your User Contributed Content is subsequently removed by you OR if you subsequently delete your account on our Platform.

Using our right to license the content, we will distribute your User Contributed Content under the terms of the Creative Commons BY-NC-SA license. This means that any third parties using or adapting your content should attribute Exercism as the source. The CC BY-NC-SA Creative Commons license terms are explained in more detail below.

It is your responsibility to ensure that the content you upload to the Platform is compatible by the CC BY-NC-SA license and includes any appropriate attribution. This agreement means that you cannot revoke permission for us to use any content you upload.

You agree NOT to include personal information (such as, but not limited to, names, phone numbers, and email addresses) within any content you contribute to the Platform.

User Contributed Content - Moderator/Feedback content

If you participate on our Platform as a Mentor, then any content you upload as part of providing Feedback on a user's Solution will be considered User Contributed Content, and licensed in the same way as that of the Solution (see the above section).

Specifically, this means that all Mentor feedback will be licensed under a Creative Commons license. It is important that you ensure that the feedback you supply (including any further code-samples) is compatible with that license.

What is this licensing, and why are we using it?

CC BY-NC-SA is an abbreviation of the Creative Commons Attribution-NonCommercial-ShareAlike license. A full copy of this license is available at https://creativecommons.org/licenses/by-nc-sa/4.0/ . In summary, this license permits anyone to copy, adapt, and redistribute the material, so long as proper attribution is given and they do not use it for commercial purposes. When we present you with other Users' solutions or Feedback, it is licensed under CC BY-NC-SA.

When you contribute a Solution to the platform, then that Solution will be available for others (usually Mentors) to comment on. Our Platform uses this feedback to help you learn and develop. In order to achieve this, it is important that the materials you share can be legally accessed by a Mentor, and using CC BY-NC-SA helps us ensure that. Equally, when a Mentor comments on your solution, their response is also licensed in the same way, allowing you to use that feedback for any purpose you choose.

By providing us with a worldwide, royalty-free, perpetual license, you are also allowing us to use submitted solutions to improve our products and services. For example, such use might include (but not be limited to) the following examples:

  • Authoring a book describing common difficulties associated with writing software
  • Using anonymized solutions to build an AI-based code-review bot
  • Improving the user-experience of exercism.org
  • Publishing a dataset of anonymized feedback for academic analysis of the factors that determine successful peer-to-peer based feedback

In summary:

  • Because you grant us a non-exclusive license, you retain rights on your Solutions/User Contributed Content. You can re-use this content as you see fit.
  • Because you grant us an irrevocable, royalty-free, commercial license on your User Contributed Content, we are allowed to re-use and adapt this content. We will do this in ways aligned with our Values.
  • Because we present your User Contributed Content under a CC BY-NC-SA license, others can use and benefit from that content, but they have to credit our Platform (exercism.org) when they do, and may not use it for commercial purposes.

No warranties for User Contributed Content

We do not control the content uploaded on our Platform and, as such, do not provide any assurances regarding its validity, reliability or accuracy.

Although User Contributed Content may be observed by Mentors, we do not routinely screen submitted content for errors, omissions or inappropriate content. Your use of the content on our Platform is at your own risk and we shall have no liability for such use.

The appearance of User Contributed or Community Content on our Platform does not imply our endorsement of that material.

Concerns about content licensing

We respect all copyright and other laws relating to content and information and will not tolerate breach of such laws.

If you believe that content of yours infringes or breaches any law or regulation it is your responsibility to take steps to correct the situation. Similarly, if your content is inaccurate or could pose a risk to a third party, it is also your responsibility to take appropriate steps to correct the situation.

If you believe that content on our Platform violates any laws or regulations, You should report it to Us.

Personal information and security

We try to minimize the amount of personal data we hold, and where we do store and capture personal information, this will be governed by our Privacy Policy and such data will only be used for the purposes it was collected for.

Knowingly providing false personal information is a breach of these Terms and might result in termination of your account.

When you delete your account, we erase all the personal details from your account. This is an irreversible process, so please be sure before you delete your account. Your solutions and any comments made as a mentor will still remain the Platform but will be anonymized.

Advertising and Sponsorship

We may, from time to time, sell advertisement space on our platform. Some adverts may be platform-wide, some may be scoped to certain areas of the website. We do not target advertising based on your personal data.

We may, from time to time, allow third parties to 'sponsor' certain features of our Platform. You may, for instance, see this sponsorship information as an advert on various Platform features (including email notifications).

We periodically review the level of granularity we provide for controlling marketing-related features and may notify you of any of these changes by email.

Warranties and Indemnification

Platform Availability

We provide the core Platform to our users on a free of charge basis. We will use reasonable efforts to make our Services available 24/7/365, but from time-to-time we will have scheduled outages for maintenance purposes.

Where feasible, we may inform users about planned outages but we are under no obligation to do so, and in any case will not be liable for any service downtime.

Service Warranties

Our services and the data and content within our Platform are provided on an "as is" basis.

To the maximum extent allowed by law, Exercism disclaims all warranties and representations of any kind, including without limitation the implied warranties of fitness for a particular purpose, and non-infringement, whether express, implied, or statutory.


You hereby indemnify, defend and hold harmless us, Our affiliates, officers, directors, agents, partners, employees, representatives and third party providers from and against all reasonably foreseeable losses, expenses, damages, costs, claims and demands, including reasonable legal fees and properly incurred associated costs and disbursements, due to or arising out of Your breach of any representation or warranty under these Terms.

Our communication with you

By using our Platform or communicating generally with Us, You agree that we may communicate with You electronically regarding security, privacy, and administrative issues relating to Your use of the Platform or changes to these Terms.

If it is brought to our attention that there is any security breach, We may attempt to notify You electronically by posting a notice on the Site or sending an email to You.

Within our Platform we invite you to configure your notification preferences describing what and when you would like us to contact us you about.