Privacy

Last updated 7 September 2026

Sinew is training-plan software for coaches and the athletes they work with. It is run by Jeremy Ettlinger. This page describes what it actually stores and does, in plain language. If something here is unclear, write to jeremy.ettlinger@gmail.com.

What Sinew collects

From signing in with Google. Your email address, your name, and your profile picture. Sinew requests only the email and profile scopes, which is the narrowest pair Google offers. It cannot read your Gmail, Drive, Calendar, Contacts, or anything else in your Google account, and it never receives your Google password.

What you type in. The athletes you add and anything you record about them, including their name, sport, and your notes; the training plans, plan branches and revisions you create; your playbooks; and the sessions you log. Sinew does not ask for athletes' contact details, dates of birth, medical records, or payment information, and you should not put them in the notes field.

Automatically. Product analytics through PostHog, covering which pages and features get used. These events deliberately carry no names, email addresses, plan contents, or playbook text. Server errors are recorded so they can be fixed, along with an audit log of account changes that keeps the time, the acting account, an IP address, and a browser user-agent string.

If you are an athlete

Athletes do not have Sinew accounts. Your coach creates a record about you and controls what it says, in the same way as a notebook or a spreadsheet they keep about your training. To see or remove what is held about you, ask your coach first, since they can delete it directly. You can also write to the address above and it will be removed.

Where it is stored

On Cloudflare, in the United States. The database is Cloudflare D1 and file storage is Cloudflare R2, both pinned to Cloudflare's eastern North America region. Traffic is encrypted in transit. Your session is a single signed cookie; Sinew sets no advertising or cross-site tracking cookies.

How long it is kept

Your content is kept until you delete it. Deleting your account starts a 30-day grace period, during which you can cancel and get everything back; after that the account and its data are permanently removed.

The database is backed up once a day and those backups are kept for 90 days. This creates a gap worth stating rather than glossing over: for up to 90 days after a permanent deletion, a backup taken before you deleted may still contain some of the deleted rows. Those backups exist only to restore the service after a failure, they are not searched or used for anything else, and they age out on their own.

One further detail, for completeness. Plan contents are stored by a fingerprint of the text itself, so identical text written by two different coaches is stored once. A deletion removes your plans and their history, but a block of plan text that another coach's plan also refers to is not removed, because it is still in use. Such a block carries no name or account attached to it.

What Sinew does not do

It does not sell your data or your athletes' data. It does not show advertising, and it does not share anything with advertisers or data brokers. Your plans, playbooks and notes are not used to train any machine-learning model. The only companies that touch this data are the ones needed to run the service: Cloudflare for hosting and storage, Google for sign-in, PostHog for the anonymous product analytics described above, and Resend if transactional email is switched on.

Your controls

From Settings you can export everything in your account as a file, delete your account, and sign out of every device at once. Deleting is reversible for 30 days and permanent after that.

Changes

If this policy changes in a way that affects what is collected or how long it is kept, the date at the top will change and signed-in practitioners will be told. Sinew is early software and is currently free to use; see the terms of service.