Privacy policy

Last updated 12 September 2026

This page says exactly what the site stores, where, and what we do with it. The short version: without an account, nothing about you reaches our servers. With an account, we keep the few things you ask us to keep, and nothing else.

No ads, no tracking

The site has no advertising, no analytics, no tracking cookies and no third-party scripts. Even the fonts are served from the site itself, so your visit is not reported to anyone. The site's security policy, which every browser enforces, allows connections only to the site itself, to the Firebase services listed below, and to our own run server.

Without an account

Your lesson progress, the code in the sandbox editor and your editor settings are kept in your own browser's local storage. They never leave your device unless you press Run in the Java or Python sandbox (below) or create an account. Clearing your browser data removes them.

With an account

Accounts are provided by Firebase Authentication (a Google service). We store:

• Your username, and the password you chose, which Firebase stores only as a salted hash: neither we nor Google can read it.
• Your lesson progress: which lessons you have completed in each course.
• Sandbox projects you choose to save: up to two per language, each up to 256 KB compressed, with the name you gave them and when they were last saved.
• The dates your account was created and last updated.

That is the whole list. We do not collect your name, email, age, location or anything about your device. We do not read your projects. Because there is no email on an account, a forgotten password cannot be reset.

This data is stored in Cloud Firestore on Google Cloud, protected by security rules that let only you (signed in as you) read or change it. Google processes it on our behalf under its Firebase privacy terms.

Signing in keeps a session token in your browser's storage so you stay signed in on that device. Signing out removes it.

The sandbox run server

When you press Run in the Java or Python sandbox, the files in the editor are sent to our run server, compiled and run in a throwaway container with no network access, and the output is streamed back. The container and your code are discarded as soon as the run ends. Nothing is kept, with or without an account. The JavaScript and TypeScript sandboxes run entirely inside your browser and send nothing anywhere.

The run server sees your IP address, as any server does, and uses it only to limit how many programs one connection can run at once. It is not logged with your code and not linked to an account.

Children

The site is written for beginners, many of them children. We ask for no personal information from anyone, and we ask everyone not to use a real name as a username. A parent or guardian should create and look after accounts for children under 13, including keeping the password safe, since it cannot be reset.

Your data, your choice

Everything the site holds about you is shown on the account page, where you can reset your progress, delete saved projects, change your password, and delete your account, which erases all of it at once. Deletion is immediate and cannot be undone. If you have lost your password and want the account removed, email contact@lineatatime.com with the username.

We never sell or share your data, and we only disclose it if the law requires us to.

Changes

If this policy changes, the date at the top changes with it, and if the change matters we will say so on the site. Questions about privacy go to contact@lineatatime.com.