About this beta
Beta 0.2 is the real platform being built on the shape of the frozen Beta 0.1 skeleton (frozen on 3 October 2026): server, database, real accounts, real records. It is built item by item in the open, and this page says exactly where the seams are at Beta 0.2 · 2daac0a399a9611f22c34ed56d43baaa5662345c.
Leo is our AI tutor, named for Leonhard Euler and drawn from the stars of Leo, a constellation in STELLA’s sky.
At thirteen, Euler spent Saturday afternoons with Johann Bernoulli, bringing what he could not understand. Leo works the same way.
A computer program, not a person. Named for Leonhard Euler. Leo appears only in the hint panel, after your candidate asks (nothing of Leo sits on the problem itself) and, on the family plan, when coaching a missed problem. One constellation, one tutor, one red star: STELLA’s sky stays a sky, not a cast (founder, 2 October).
✓ Real in this build
- Accounts and email. A parent opens the account with a display name, an email address and a password; a confirmation link arrives by email and lives 24 hours. Passwords are hashed (argon2id) and never leave the server. Sessions are kept on the server; the cookie holds a random identifier only.
- Parent-first registration, step by step, with the eligibility rule applied as decided: 13 or younger on 31 December 2027, born on or after 1 January 2014. The child’s year of birth is the only date Euler asks; the alias is the only name (the standing rule: no child’s real name is ever stored); the school is picked from the registered list or held as pending and is never linked publicly to the child; one parent account holds several candidates.
- Consent, one tick per statement, none pre-ticked, each recorded with the exact text shown and its version; the Code of Conduct draft v0.9, word for word, each point ticked by hand. Every consent can be withdrawn from the Profile.
- The Euler ID (E-ID), as decided on 24 September: E-BBRR-XXXXX-C, that is birth year, registration year, a private random core and a check digit. Minted at registration, permanent, and always shown beside the candidate on boards, so a junior finds their own row even among withheld aliases. The full birth date never appears anywhere.
- Identity store ≠ activity store: every activity record (Eulos, adventures, the Ei history) is keyed on the Euler ID alone; the E-ID ↔ parent mapping is its own table, read only inside the parent’s session. An automated test fails the build if a child table ever gains a parent key, a date of birth, a name, a photo, a contact or an identity document.
- The candidate's own login (login name + PIN), created by the parent on the Profile page: never an email, 6 to 8 digits, five wrong PINs pause the login for thirty minutes and the parent is told by email. A child cannot create an account; a test asserts it.
- The parent’s controls: the Euler Index switch and its rule (OFF means nothing reaches any public board: not greyed out, not anonymised, fully withheld); the tutor-share switch; the candidate switcher; the school, effective-dated.
- The seven levels page, and the legal pages in the footer: the Impressum, both Privacy Notices, the Terms, the Cookie Statement and the Sub-processor List, as drafted for counsel’s review.
- The brand: the final wordmark, the red and charcoal, the type (self-hosted, nothing loaded from a third party) and the Eulos currency mark, chosen by the founder from three candidates.
◌ Not yet, and the page says so where you meet it
- The adventures. Levels 1 to 5 are playable in the candidate’s own login: ten real problems a set, composed from the pools (live problems first, calibrating ones while the pool is proving itself, never one the child has seen), the answer counted once, the clock kept by the server, Eulos as a count only, and the Euler Index written after every adventure. Leo’s hint panel carries the honesty label and says that coaching is not live yet.
- The boards exist for signed-in parents and candidates (Euler ID · alias with specific consent · country, never a school); the public page waits for the decision on how the Euler ID appears in public. The adventure report on the Profile (every problem, the answer given, the key, right or wrong, seconds, the review-tier chip and the parent’s flag) is the next build item; the record is already kept in full.
- Leo. The hint panel is not open yet. When it opens, Leo runs server-side through the platform’s own gateway, from set prompts, with no identifier in any call, and always under the label above.
- The Euler Faculty sign-up, the contribution record and the honours board; STELLA’s directory, calendar and Family space.
- Payments and plans: Insights+ and Pro and the Faculty tiers are shown for orientation only; there is nothing to buy and no payment is taken. The payments path is built dark, in test mode, and switched on by the founder only when its legal gates are cleared.
- Languages: English now; German, French and Italian at launch. Consent and privacy texts appear only in languages counsel has cleared.
- Counsel’s review of the legal drafts is pending; each legal page carries its draft status at the top.
This site sets functional cookies only (named in the Cookie Statement); no analytics, no advertising, no third-party scripts. Questions and findings: euler100@euler.swiss.