D Plus+

D Plus+ is a community platform for people learning German — a feed pitched at your level, courses, exam training, pronunciation practice, and a community that answers.

The feed carries editorial posts by the platform's own voice, Rosina: a fifteen-minute daily routine, why Germans keep saying Ach so!, eight words for a first job application with Arabic glosses, telc strategies, and full episodes of Nicos Weg. Reactions, comments, reposts, saves, a daily posting allowance, a streak, and a level badge.

Ach so! is the community: questions until it clicks, named after the German for exactly that moment.

Kurse. Nicos Weg from zero at A1, A2, and a B1 exam-fit listening course, with ratings and progress.

Sprechen. Pronunciation training with a microphone — words, sentences, or free speaking from A1 to C2 — checked by AI.

Prüfungen. Full mock exams in the real telc, Goethe and ÖSD formats: reading, listening, writing and speaking, a fresh sheet assembled from a large task bank on every start, graded by AI, with open sheets you can resume and best scores tracked.

A placement test places a newcomer; a personal assistant is one button away; tasks and a calendar keep the routine.

Why it matters. Learners do not lack material. They lack a place where writing a bad sentence is normal, gets read, and gets answered — and where the next thing they see is pitched at where they actually are.

Chronological feeds reward whoever posts most; engagement-ranked feeds reward whatever already won. Neither knows whether a B1 learner should be reading this.

D Plus+ ranks on the learner: how close a post is to their interests, how well it fits their level, whether it comes from a community they joined, how the community responded, and how fresh it is — with every one of those signals kept on the same bounded scale so no single one can quietly take over the ranking. Interests are seeded by the onboarding survey and updated by what the learner actually does, and they fade over weeks, so a shifting focus moves the feed without any setting to change. What the feed merely showed someone is deliberately not treated as a signal, because that closes a loop in which the ranker confirms its own first guess forever.

Try it: move the sliders, then switch engagement to an unbounded count and watch a small weight become the whole ranking.

Everything a member writes goes live immediately and is reviewed seconds later. Review takes content down; it is not what lets it up.

That order is a product decision, not a shortcut. A learner writes a sentence in a language they are still learning and then watches nothing happen — and that delay lands hardest on exactly the people the platform exists for. The reviewer transcribes audio, classifies what it finds, and the platform — not the model — decides the consequence from a written policy. When the reviewer cannot decide or breaks, the post stays visible for a person to look at: "not sure" is not a finding. Every hold is explained and appealable.

Technologies: Gemini for transcription and classification, Postgres, Supabase.

Paymob, the Egyptian gateway: authorise, capture, void, refund, verified callbacks and a settlement worker that pays teachers out. Every callback is verified before it is trusted; an unverified payment callback would be an endpoint that lets anyone mark a lesson as paid, so the integration fails closed.

Visibility and permissions are enforced in the database with row-level security, and no client can promote its own content or undo a moderation decision from the outside.

Technologies: Next.js 16, React 19, Supabase / Postgres with RLS, Paymob, Web Push, next-intl (German + English), Vercel.