# What does Composer use?

Composer (usecomposer.com) shows public evidence of 7 tools, according to runsonwhat (last checked 2026-10-23).

## Edge & Hosting

| Tool | Category | Evidence | Since |
|---|---|---|---|
| [Cloudflare](https://www.runsonwhat.com/reverse/cloudflare) | CDN & Edge | Email records, DNS records, Website code |  |
| [Vercel](https://www.runsonwhat.com/reverse/vercel) | Hosting & Cloud | Website code |  |

## Application

| Tool | Category | Evidence | Since |
|---|---|---|---|
| [Google Fonts](https://www.runsonwhat.com/reverse/google-fonts) | Media & UI | Website code |  |

## Data & Observability

| Tool | Category | Evidence | Since |
|---|---|---|---|
| [Sentry](https://www.runsonwhat.com/reverse/sentry) | Monitoring | Website code |  |
| [web-vitals](https://www.runsonwhat.com/reverse/web-vitals) | Monitoring | Website code |  |
| [PostHog](https://www.runsonwhat.com/reverse/posthog) | Analytics | Website code |  |
| [Vercel Analytics](https://www.runsonwhat.com/reverse/vercel-analytics) | Analytics | Website code |  |

## FAQ

### What tools does Composer use?

As of October 2026, runsonwhat has found 7 tools at Composer (usecomposer.com) in public records. Edge & Hosting: Cloudflare and Vercel. Application: Google Fonts. Data & Observability: Sentry, web-vitals and PostHog. Last checked October 23, 2026.

### What cloud does Composer run on?

Composer uses Vercel for hosting and cloud infrastructure, according to runsonwhat (October 2026). runsonwhat found Vercel through Vercel code on usecomposer.com. Vercel is used by 49,657 companies runsonwhat tracks.

### What analytics tools does Composer use?

Composer uses PostHog for analytics, alongside Vercel Analytics, according to runsonwhat (October 2026). runsonwhat found PostHog through PostHog code on usecomposer.com. PostHog is used by 10,302 companies runsonwhat tracks.

### What monitoring tools does Composer use?

Composer uses Sentry for monitoring, alongside web-vitals, according to runsonwhat (October 2026). runsonwhat found Sentry through Sentry code on usecomposer.com. Sentry is used by 79,319 companies runsonwhat tracks.

### Does Composer use Google Fonts?

Yes. runsonwhat found Google Fonts at Composer through Google Fonts code on usecomposer.com. Google Fonts is a Media & UI tool used by 818,277 companies runsonwhat tracks.

### How does runsonwhat know what Composer uses?

runsonwhat reads public records only. Of the 7 tools at Composer, 6 were found through code on usecomposer.com, 1 through email records. A tool is listed only when a direct record backs it up; DNS is rechecked weekly and usecomposer.com about monthly.


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Source: runsonwhat, https://www.runsonwhat.com/company/usecomposer.com (updated October 2026). Counts are companies with direct public evidence of the tool (DNS records, certificates, website code, a real-browser crawl, subprocessor lists), so they are lower bounds. Methodology: https://www.runsonwhat.com/methodology.