# Slowest journeys, end to end

Prompt · Performance and scale · P01

Shows where the seconds go on the paths people actually use.

## Prompt

```text
Trace the five most expensive user journeys from browser interaction to database response. Find unnecessary round trips, waterfalls, serialization, and repeated computations, and measure their contribution to latency.
```

**What it returns:** A timed trace per journey (browser network panel, server timing, query time) with each step's share of the total.

**Skip it when:** When nobody has reported slowness and costs are flat.

**Tools:** Browser developer tools or Playwright recordings, server logs or timing data, and the database's query plan (EXPLAIN).

**Watch for:** Static reading guesses at latency. Require a measured trace before any ranking.

**Changes:** Changes nothing

**Sessions:** Look first, then fix in a new session

## Skills

- [diagnosing-bugs](https://www.atlasscope.dev/skills/diagnosing-bugs): Diagnosis loop for hard bugs and performance regressions.

## Related

- [Steps that wait for no reason](https://www.atlasscope.dev/prompts/steps-that-wait-for-no-reason): Finds steps that wait for each other to finish when they could run at the same time.
- [Queries that grow badly](https://www.atlasscope.dev/prompts/queries-that-grow-badly): Finds the database queries that will be the first to slow down as tables grow.
- [Reproduce, measure, prove](https://www.atlasscope.dev/prompts/reproduce-measure-prove)

Source: https://www.atlasscope.dev/prompts/slowest-journeys-end-to-end