Exam Studio

The Problem

NCTB-standard exam papers with complex Bengali typography, formulas, and 2×1 booklet imposition often require bulky TeX Live installations or costly, privacy-sensitive backend compilation.

What It Does

• ✓100% client-side XeLaTeX compilation in WebAssembly using texlyre-busytex with zero server latency or hosting costs
• ✓Bengali OpenType font shaping with Kalpurush.ttf via fontspec and polyglossia packages
• ✓Automated NCTB-standard paper formatting for Creative Questions (CQ), Short Questions (SQ), and 2-column MCQs with dynamic option grid layouts
• ✓Automated 2x1 landscape booklet imposition ({pLast, pFirst, pSecond, pThird}) and document merging via pdf-lib
• ✓Dual Web Worker architecture offloading asset downloading and multi-pass WASM compilation from the UI thread
• ✓30-day instant persistent caching in IndexedDB with background verification and pre-warming
• ✓Monaco JSON editor with Zod schema validation, Bengali math symbol quick-input bar, and mobile clipboard integration
• ✓High-DPR HTML5 PDF canvas viewer with dynamic fit-to-width and IntersectionObserver scroll tracking

How It Works & Architecture

Technical Challenges

• !Compiling complex Bengali font shaping (fontspec/polyglossia) inside memory-constrained browser WebAssembly runtimes without crashing mobile tabs.
• !Designing automated 2x1 booklet imposition algorithms that correctly calculate page signatures and offsets for double-sided folding.
• !Managing a 78MB compiler bundle efficiently using IndexedDB chunked caching and persistent storage locks.

What I Learned

• ★Heavy computational workloads like LaTeX typesetting can run entirely on client machines with WebAssembly and Web Workers, eliminating server scaling costs.
• ★Decoupling font shaping and asset management into dedicated worker threads keeps the editor UI responsive at 60 FPS.