Lexilink

Overview

Lexilink is the flagship application in the monorepo — a multi-subject learning platform supporting vocabulary management, spaced repetition (SM-2 algorithm), testing, class collaboration, gamification, and a content marketplace. It is the most feature-rich app with 145 Convex tables and 109 function files.

Production URL: lexilink.app

Documentation: Lexilink has its own dedicated Mintlify docs at docs.lexilink.app

Key Features

• Vocabulary Management — Create, organize, and share vocabulary sets across subjects
• Spaced Repetition — SM-2 algorithm with ease factor, interval, and next-review tracking
• Testing — Create and take assessments with multiple question types and grading
• Class Collaboration — Teacher-managed classes with join codes, assignments, and announcements
• Gamification — Points, streaks, achievements, and student duels
• Content Marketplace — Browse, publish, and share learning content
• Subject Templates — Flexible template system supporting any subject beyond vocabulary
• AI Features — AI-powered study assistance via OpenRouter

Tech Stack

Component	Technology
Framework	Next.js 16 (App Router, Turbopack, React Compiler)
Backend	Convex (145 tables, 109 function files)
Auth	@convex-dev/auth (Password + OAuth)
UI	shadcn/ui + Tailwind CSS 4.0
i18n	next-intl (6 languages: en, fr, it, de, la, ar)
Payments	Stripe (Free/Pro/Team/Enterprise/Institution tiers)
AI	OpenRouter + LM Studio
Forms	React Hook Form + Zod

Architecture

Lexilink uses a feature-first component architecture with 36 domain-specific modules:

components/
  features/         # 36 feature modules
    vocabulary/     # Vocabulary CRUD
    study/          # Study sessions, flashcards
    tests/          # Test builder and taking
    classes/        # Class management
    dashboard/      # Dashboard widgets
    gamification/   # Points, streaks, achievements
    marketplace/    # Content marketplace
    templates/      # Subject template editor
    ...
  shared/           # Cross-domain (auth, layout, i18n)
  ui/               # shadcn/ui primitives

The middleware uses proxy.ts (Next.js 16 pattern) combining Convex Auth and next-intl for authentication and locale routing in a single middleware layer.

Convex Schema

The database contains 145 tables organized into domains:

Domain	Key Tables
Core	users, institutions, classes, classEnrollments
Content	vocabularySets, vocabularyItems, subjectTemplates, tests, testSubmissions
Learning	progress (SM-2 tracking), studySessions
Features	achievements, streaks, announcements, marketplaceListings

User Roles

Five roles with escalating permissions:

1. student — Study, take tests, join classes
2. teacher — Create content, manage classes, grade
3. school_admin — Manage institution settings
4. parent — Monitor student progress (read-only)
5. platform_admin — System-wide management

Internationalization

Lexilink supports 6 languages with 35 translation domain files:

Language	Code	Direction
English	en	LTR
French	fr	LTR
Italian	it	LTR
German	de	LTR
Latin	la	LTR
Arabic	ar	RTL