Harbor Language LMS — complete Crystal learning platform example app

This repository contains the complete source for Harbor Language LMS, an open-source learning platform built with Crystal. Build a polished, production-quality MVP for a language learning management system (Harbor) using the Kemal framework in Crystal. Everything Harbor Language LMS needs to run is here — code, seed data, install scripts. Apache-2.0-licensed — use Harbor Language LMS commercially, self-host it, or remix Harbor Language LMS on cenius.ai to make it yours.

▶ Open & edit in cenius.ai — one click to an editable workspace: describe changes in plain English, get an instant preview, one-click deploy and host. Modifications made on the platform come with full rebrand & relicense rights.

Local clone? See Quick start below. cenius.ai is the zero-setup path.

Demo

📽 Demo video on cenius.ai — the complete run-through ·

Screenshots

Quick start

./install.sh   # installs dependencies + seeds demo data

See INSTALL.md for full setup and usage instructions.

Architecture

./install.sh gets you from a fresh clone to a running instance with sample data in a single step. The Crystal codebase (271 files) is self-contained — no external services needed to evaluate it. Top-level layout: bin/, lib/, public/, src/. Full setup details: INSTALL.md.

Usage guide

Once the development server is running (crystal run src), open a browser and navigate to http://localhost:3000 (or the configured URL).

Web Interface

Public pages

• Home (/) Lists the available courses. No login required.

• Authentication

  • Register (/auth/register) – Create a new account.
  • Login (/auth/login) – Sign in to access your dashboard.

Authenticated pages

• Dashboard (/dashboard) Shows the courses you are enrolled in and your progress.

• Courses

  • Course index (/courses) – Browse all courses.
  • Course detail (/courses/:id) – View course information and its lessons.
  • Lesson view (/lessons/:id) – Read lesson content.

Example cURL Commands

## Fetch the home page
curl http://localhost:3000/

## List all courses
curl http://localhost:3000/courses

## View a specific course (replace 1 with an actual course id)
curl http://localhost:3000/courses/1

## View a specific lesson (replace 1 with an actual lesson id)
curl http://localhost:3000/lessons/1

Protected routes (e.g., /dashboard) require session authentication. Log in via the browser to obtain a session cookie before using cURL for those routes.

Theming

A theme toggle is available in the page header to switch between light and dark mode. The preference is stored in your session.

Full guide: USAGE.md

FAQ

How do I self-host Harbor Language LMS?

It runs entirely on your own machine. Clone, run ./install.sh, and follow INSTALL.md — the whole stack is in this repo, no external dependencies required.

Can I rebrand or white-label Harbor Language LMS?

Absolutely. Open it on cenius.ai and remix it there — platform modifications come with full rebrand and relicense rights over your derivative, so the result is entirely yours.

Can I use Harbor Language LMS in a commercial project?

It is. Apache-2.0 licensing means you can build a product on it, sell it, or use it inside a company with no fees. Details: LICENSE.

Which technology stack does Harbor Language LMS use?

Crystal end-to-end. Every file you need to run the app is here in this repository — code, configuration, seed data.

Can I change Harbor Language LMS without writing code?

Describe what you want changed on cenius.ai — no code editing needed; the platform produces a fresh build you can download and deploy.

License & rebranding

Released under the Apache License 2.0 (© 2026 Cenius AI) — free for personal and commercial use. The Cenius name/logo are trademarks (see NOTICE).

Need a customized version? Remix this app on cenius.ai — modifications made on the platform come with full rebrand & relicense rights over your derivative.

Built with cenius.ai

This entire application — code, design, seeded demo data — was generated on cenius.ai from a plain-English description.

• 🚀 Build your own app on cenius.ai
• 🎛️ Remix Harbor Language LMS on the marketplace — open it in a workspace, prompt for changes, and ship your own version.

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