Bun is the blazing-fast all-in-one JavaScript runtime, package manager, and bundler — but as a developer toolchain, it has no built-in WCAG accessibility audit, no Core Web Vitals scoring, and no front-end health monitoring. PageGuard audits the live URL of any Bun-powered application externally — free, no code changes needed, results in 30 seconds.
ADA Title II Deadline: April 24, 2026
State and local government websites must meet WCAG 2.1 AA by April 24, 2026. Government agencies, nonprofits, and educational institutions using Bun to build and serve web applications face this compliance deadline. Bun’s fast bun build makes it easy to push front-end changes rapidly — but speed doesn’t include a WCAG quality gate. Any build and deployment can push accessibility regressions to users with no automated check. PageGuard provides continuous post-deployment front-end monitoring without requiring code changes or Bun server access.
bun install 3x faster than npm), bundler (bun build faster than esbuild), test runner (Jest-compatible); native TypeScript/JSX without transpilation; built-in SQLite3; Bun Shell
bun run executes package.json scripts; works with React, Next.js, Vite, Express, and most npm packages; macOS, Linux support (Windows experimental)
| Feature | PageGuard | Bun |
|---|---|---|
| What is it? | External website health monitor — scans any URL for performance, accessibility, SEO, and best practices | All-in-one JavaScript/TypeScript runtime, package manager, bundler, and test runner; designed as a drop-in Node.js alternative with 3x faster startup and npm compatibility; written in Zig with JavaScriptCore engine; ~75K GitHub Stars; Bun v1.0 released September 2023; Bun Cloud (managed hosting) in development; Bun Shell for cross-platform shell scripts |
| Free tier | ✓ Yes — unlimited one-off scans, no signup required | Yes — Bun runtime is free and open-source (MIT license); bun install, bun run, bun build, bun test are all free CLI tools; Bun Cloud hosting (when released) expected to have a free tier; no SaaS subscription required to use Bun as a runtime |
| Accessibility audit (WCAG / ADA) | ✓ Yes — WCAG 2.1 AA scored 0–100 with specific issue list | No — Bun is a JavaScript runtime and toolchain; it executes JavaScript/TypeScript server-side and bundles front-end assets but has no built-in WCAG or ADA accessibility auditing for the HTML output rendered by applications using it; accessibility quality is entirely determined by the application code |
| Technical SEO audit | ✓ Yes — meta tags, headings, canonical, structured data | No — Bun provides no SEO audit scores, meta tag validation, heading hierarchy checks, or structured data analysis; it runs JavaScript faster and bundles assets but does not inspect or audit the HTML output for SEO quality |
| Performance audit (Core Web Vitals) | ✓ Yes — LCP, CLS, FCP scored 0–100 per scan | No — Bun provides no Core Web Vitals measurement (LCP, CLS, FCP, INP) for applications it serves; while Bun's faster startup and HTTP server improve server-side latency, it does not measure front-end rendering performance from a user perspective |
| JavaScript runtime & toolchain | No — PageGuard is a monitoring tool, not a runtime | ✓ Yes — Bun is a complete JavaScript/TypeScript runtime (JavaScriptCore), package manager (bun install — 3x faster than npm), bundler (bun build — faster than esbuild), and test runner (bun test — Jest-compatible); native TypeScript/JSX support without transpilation; Node.js API compatibility; Bun.serve() for HTTP servers; WebSocket support; SQLite3 built-in; Bun Shell for cross-platform shell scripts |
| Developer toolchain | No — PageGuard is a SaaS monitoring service | ✓ Yes — bun install: installs npm packages from package.json 3x faster than npm, 10x faster than Yarn; bun run: executes scripts with zero config; bun build: bundles TypeScript/JSX/CSS for production; bun test: runs Jest-compatible tests with watch mode; bun create: scaffolds new projects; Bun.file() for fast file I/O; native .env loading; macOS, Linux, and Windows (experimental) support |
| Automated website monitoring | ✓ Yes — weekly or daily scans with email alerts on score drop | No — Bun has no post-deployment front-end health monitoring for WCAG compliance, Core Web Vitals regressions, SEO quality, or best practices for rendered HTML; Bun.serve() access logs track HTTP requests — not front-end quality metrics |
| AI-generated plain-English report | ✓ Yes — explains issues in non-technical language | No — no front-end health report for applications built and run with Bun |
| ADA Title II compliance monitoring | ✓ Yes — WCAG audit + alert on accessibility regression | No — Bun does not audit or alert on WCAG compliance for applications it runs; government agencies, nonprofits, and educational institutions using Bun to serve web applications face ADA Title II compliance requirements; any bun run start or Bun.serve() deployment can push front-end accessibility regressions to users with no quality gate; React, Solid, and other framework components bundled with bun build can introduce ARIA issues, keyboard navigation gaps, and missing alt text with every build |
| Works on any platform | ✓ Yes — scans any URL on any front-end or platform | No — Bun only manages applications on servers where it is installed; it does not audit sites hosted elsewhere |
| Independent external audit | ✓ Yes — third-party scan, shareable URL for clients/stakeholders | No — no built-in tool to generate a shareable external front-end health report for applications running on Bun |
| Instant on-demand scan | ✓ Yes — results in 30 seconds, no code changes needed | No — no on-demand front-end health scan; auditing applications running on Bun requires separate tools like Lighthouse or axe |
| Multi-site dashboard | ✓ Yes — 1–50 sites depending on plan | Bun has no multi-site health monitoring dashboard; there is no dashboard showing WCAG accessibility, SEO, and Core Web Vitals scores across multiple applications built with Bun |
| Pricing for health monitoring | ✓ Free + from $9/mo for automated monitoring | Health monitoring not available — Bun runtime is free open-source; front-end health monitoring requires a separate tool |
bun build and deployment to catch accessibility and SEO regressions in React, Solid, or other JSX components before users encounter themGet WCAG accessibility scores and Core Web Vitals for any application built or served with Bun. Results in 30 seconds. No server access or code changes required.
Results in ~30 seconds. 4 scores: Performance, Accessibility, SEO, Best Practices.
Yes — PageGuard scans the live URL of any application built or served with Bun. Enter your app’s public URL and receive a full health report in ~30 seconds covering Core Web Vitals, WCAG 2.1 AA accessibility, technical SEO, and best practices. No Bun installation access or application code is required.
No — Bun is a JavaScript runtime and developer toolchain with no built-in WCAG compliance checking. It executes JavaScript/TypeScript faster than Node.js and bundles front-end assets but does not audit the HTML output for accessibility issues. Common problems include missing alt text on images, improper heading hierarchy in JSX, insufficient color contrast in CSS, missing ARIA labels on interactive components, and keyboard navigation gaps in React or Solid apps. PageGuard audits your live application and provides a WCAG 2.1 AA score with specific issues to fix.
Bun’s fast build and start times make it easy to push front-end changes rapidly — but speed doesn’t include a WCAG quality gate. Any bun build followed by deployment can push accessibility regressions to users with no automated check. Government agencies, nonprofits, and universities using Bun face ADA Title II compliance with an April 24, 2026 deadline. PageGuard provides continuous post-deployment monitoring with email alerts when WCAG scores drop.
No — they serve completely different purposes. Bun is an all-in-one JavaScript/TypeScript runtime, package manager, bundler, and test runner built for speed. PageGuard is an external quality monitoring tool for the front-end output of applications built and served with Bun. Developers using Bun for faster builds should add PageGuard to continuously verify WCAG compliance, Core Web Vitals, and SEO quality after each deployment.