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Built · not publicly deployed
EdTech / Developer Education

JS Academy Learning Platform

A JavaScript learning platform that makes execution visible — step through your code one instruction at a time.

test suites and files
113
forward-only migrations
25
routes WCAG 2.2 AA clean
9/9
critical RCE found in our own code
1
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Feature-complete and running locally; public deployment is the next step. Demo available on request.

Execution visualiser — stepping through a closure (call stack, scopes, heap, step log)
Execution visualiser — stepping through a closure (call stack, scopes, heap, step log)

The problem worth solving

Learning JavaScript stalls where execution is invisible — closures, the call stack, the event loop and recursion are hard to grasp from static text, and generic courses can’t verify a learner actually understands or is interview-ready.

How it works

JS Academy teaches JavaScript by making a running program visible: a custom step-through visualiser walks any snippet one instruction at a time with a live call stack, scopes and closures, the heap, and — for data-structures work — a structure view with a running time/space complexity meter. Around it sit a ten-tier curriculum from “Hello, JavaScript” through async, data structures, TypeScript, testing, backends and React, with server-graded challenges and spaced review; a curated bank of real company assessment questions; and an AI-powered interview-prep suite (coach, mock interviewer, and behavioural-story rehearsals). Authors add lessons through a role-gated admin console with a structured content editor and a draft → preview → publish flow.

What the business gets

  • A from-scratch execution visualiser: step through real code with a synchronised call stack, scopes/closures, heap and step log
  • Six companion players for what the stepper can’t lay out — event loop, recursion call-tree, tree/graph, grid, linked-list and a race view
  • A ten-tier curriculum (Hello JavaScript → async → DSA → TypeScript → testing → backends → React) with server-graded quizzes and challenges, plus 2/7/21-day spaced review
  • A curated company question bank — real assessment questions by difficulty, company and pattern, each with a ranked difficulty and an authored solution that loads straight into the stepper
  • An AI-powered interview-prep suite: coach, mock interviewer with scorecards, a mistake journal and a readiness dashboard — with admin-managed access control and per-user spend visibility
  • A placement test and date-driven study planner that gives honest infeasibility warnings rather than false comfort
  • A role-gated admin console to author lessons and challenges with a structured, validated content editor
  • Learner code runs in a sandbox, never on the page itself — a mistake or a malicious paste cannot break the lesson or reach anything else
  • Usable by keyboard alone and with a screen reader, verified against WCAG 2.2 AA on every release
  • Stress-tested before launch across correctness, load, security and accessibility — with the findings and the remaining risks written down rather than glossed over

Screens

Verified 2026-09-04. Re-run in js-academy: test suites/files from `npm test` (37 server suites + 76 client files = 113, up from the 101 claimed before today), migrations from `ls server/src/db/migrations/*.sql` (25 — not 22, and not under server/migrations), WCAG routes from the a11y CI job (9/9). Not publicly deployed.