What it does
SpeedCurve monitors website performance using scheduled synthetic tests and real-user monitoring (RUM). Teams can track Core Web Vitals, set performance budgets, inspect page-level regressions, and connect performance checks to a CI/CD workflow. Synthetic checks show repeatable lab results, while RUM adds evidence about what visitors actually experience. It is aimed at web performance teams that need trends and regression signals rather than a general-purpose application metrics or log platform.
Set up a site around the pages that matter
SpeedCurve's setup documentation starts in the web app's Settings. Add a site and the URLs that represent important journeys, then choose synthetic test regions, browsers, schedules, and check counts. Synthetic tests let a team compare repeatable page loads over time; RUM complements them with measurements from actual browser sessions. Use labels and dashboards to keep high-value pages, such as a product listing or checkout flow, easy to compare.
A practical first task is to monitor one revenue-critical URL before expanding to the whole site. Set a performance budget and notifications for a meaningful regression, then connect the test or deployment workflow to CI/CD if you want to catch changes before release. SpeedCurve's API is REST-based and supports tasks such as reading sites and test results, exporting RUM data, and recording deployments, which can fit an existing release process.
Budget RUM deliberately
RUM sampling is controlled in Settings or through the JavaScript API. The documentation says sampling is session-based, preserving a user's journey in the sampled data. A useful tip is to use a lower rate for mostly static marketing pages and a higher one for pages where behavior changes with user state. When the rate is changed in Settings, a decrease may take up to 15 minutes to propagate; an increase can take longer because the lux.js snippet may remain cached in visitors' browsers.
Plans are available monthly or annually, and the plan size depends on synthetic checks and RUM page views. The pricing page uses a configurable plan builder, so an exact total depends on the volumes selected. SpeedCurve is now part of Embrace, but its official site says the product remains in use without a change to how customers use it.
Strengths
- Combines synthetic browser tests and RUM so repeatable lab performance can be compared with real visitor experience.
- Performance budgets, regression alerts, Core Web Vitals, and CI/CD integrations support performance checks before and after deployment.
- A REST API can retrieve test and RUM data and record deployment events for external workflows.
Watch out for
- RUM sample-rate changes made in Settings do not take effect immediately; increases may take days while cached copies of the browser snippet expire.
Best for
- Web teams setting performance budgets for key journeys and tracking regressions across releases
- Comparing repeatable synthetic tests with Core Web Vitals and real-user page performance
- Automating performance reporting or deployment annotations through an API
Sources
- SpeedCurve by Embrace | Website Performance Monitoring (Oct 26, 2026)
- Setup Guide (Oct 26, 2026)
- Sample rate (Oct 26, 2026)
- Sign up for a plan (Oct 26, 2026)
- Getting Started - SpeedCurve API (Oct 26, 2026)