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ASU ProfessorView

Chrome Web Store extension that integrates Rate My Professor ratings directly into Arizona State University's class search interface.

Students can view ratings, review counts, difficulty scores, and top tags inline while browsing courses, eliminating the need to cross-reference multiple tabs.

Result: Published to the Chrome Web Store with a 5-star rating.

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Overview

Course planning at ASU typically requires switching between the university catalog and Rate My Professor to evaluate instructors. This extension augments the catalog in place by detecting instructors in the search results, retrieving their rating data, and injecting a structured UI card into the page without impacting performance.

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Key Features

• Inline professor rating cards inside the ASU catalog
• Support for multiple ASU campuses (Tempe, Polytechnic, West)
• Compact and expanded display modes
• Optional tag visibility
• Synchronized user preferences via chrome.storage.sync

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Technical Highlights

Platform Architecture

• Chrome Manifest V3
• Background service worker
• Content script for DOM augmentation
• Options page for persisted configuration

Data Layer

• Rate My Professor API integration through the background worker

• Intelligent cross-campus result validation

• Name normalization system for handling:

  • Hyphenated names
  • Spliced names
  • Catalog/RMP mismatches

Performance Strategy

• In-memory cache

  • 5-minute TTL
  • LRU-style eviction
  • 100-entry cap

• Serialized request queue with rate limiting

• Failure caching to prevent repeated bad requests

DOM Integration

• MutationObserver to detect dynamically loaded course results
• Debounced processing to avoid redundant work
• Targeted DOM injection without repeated full-page scans

Build System

• Vite-based build pipeline

• Custom plugin for copying:

  • manifest
  • static assets
  • extension HTML/CSS

• Output structured for unpacked extension loading

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System Architecture

Layer	Responsibility
Content Script (content.js)	Scans the catalog, extracts instructor names, sends structured messages, injects rating cards
Background Service Worker (background.ts)	API communication, caching, request queue, campus validation, name matching
Options Page (options.ts/html)	User settings for layout and tag visibility stored in chrome.storage.sync

This separation keeps DOM logic, network logic, and user configuration independent and maintainable.

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Engineering Challenges

Manifest V3 Constraints

• No persistent background process
• Service worker lifecycle management
• Fully asynchronous message passing

Unreliable External Data

• Inconsistent professor naming across systems
• Need for deterministic matching strategy
• Caching of failed lookups

Third-Party Page Augmentation

• Non-blocking execution
• Minimal layout shift
• Safe DOM injection

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What I Learned

• Designing resilient integrations against inconsistent external data
• Managing application state in a service-worker-based architecture
• Building a performant client-side caching and request queue system
• Applying defensive programming for production browser extensions
• Shipping and maintaining a real-world distributed front-end system under platform constraints

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