Duolingo-style AI concepts learner
The assignment
Build an app that makes you learn AI concepts the Duolingo way. Wire it up with PostHog for analytics.
✳What Saurab shipped
AI Quest is a fully open, no-login Duolingo-style skill tree spanning Beginner, Intermediate, and Advanced tracks. Its curriculum covers What is AI, Machine Learning, Deep Learning, Neural Networks, LLMs, Prompt Engineering, Embeddings, Vector Databases, RAG, AI Agents, and MCP. Each lesson pairs a concept card with a key takeaway, and the app tracks a streak counter, XP, a lesson progress bar, and an achievement-badge system across a locked/unlocked level tree.
✳Our read on this build
Saurab shipped a deployed web app you can open. Parts of it sit behind a sign-in, so this read leans on what is public plus Saurab's own description.
What it demonstrates
- The return loop is real: streaks, XP and badges — the mechanics that make a habit instead of a bookmark.
- The syllabus is the real vocabulary — embeddings, RAG and vectors — not a tour of how AI is changing everything.
What is not shown
- No analytics wiring is visible in what is public, so how the app is really used stays unknown — including to its builder.
Take this awayTwo things travel from this build: short lessons beat comprehensive ones, and events defined before launch beat opinions formed after it.
✳Why this quest matters
Retention is a design problem, not a content problem. Wiring PostHog in from day one is the tell of a builder who ships to learn from real behaviour — rather than to admire their own screenshot.
✳What separated the strongest builds
A loop worth coming back to
Bite-sized lessons, instant feedback, and a reason to return tomorrow — streaks, XP, spaced review. A long article with a quiz at the end is not the Duolingo shape.
Concepts that are worth the streak
Tokens, embeddings, attention, hallucination, RAG — the vocabulary a PM needs in a real conversation, not 'what is AI' trivia.
Instrumented, not just launched
PostHog wired in and firing real events. An analytics claim nobody can verify tells a reader nothing about how the product is used.
No numeric scores are published here. These pages are written reads of what each builder shipped — the build is the point, not a mark out of a hundred.