# Composal vs ESLint

ESLint reports source-level diagnostics according to configured rules. Composal runs browser scenarios against the application, checking outcomes that lint rules cannot establish from source alone.

## Composal

Composal sends AI browser agents to use your running web app and check the outcomes you care about. Define journeys as plain-English Scenarios, map existing flows with Discovery, or explore for bugs with Deep Scan. Runs keep recordings and reproduction steps so your team or coding agent can investigate a Finding.

[Verify documentation](https://composal.com/docs/verify)

## ESLint

Configurable linting for JavaScript and related code

ESLint is a pluggable JavaScript linter that analyzes code for problematic patterns and style rules. Teams configure core rules and add ecosystem plugins.

## What each tool does

| Workflow | Composal | ESLint |
| --- | --- | --- |
| [Run browser journeys](https://composal.com/product/scenarios) | ✓ Yes: Run saved browser Scenarios and return recordings and reproducible Findings. | × No: The documented product reviews or analyzes source changes; it does not execute browser journeys. |
| [Map application workflows](https://composal.com/product/discovery) | ✓ Yes: Discovery maps key application areas and user journeys. | – Not confirmed: Check whether this product includes this workflow in your intended plan and setup. |
| [Explore for unexpected issues](https://composal.com/product/deep-scan) | ✓ Yes: Deep Scan explores the running application and reports reproducible issues. | – Not confirmed: Check whether this product includes this workflow in your intended plan and setup. |
| [Describe checks in plain English](https://composal.com/product/scenarios) | ✓ Yes: Author Scenarios around the intended user outcome, then review the steps and expected results. | – Not confirmed: Check whether this product includes this workflow in your intended plan and setup. |
| [Run or inspect from a terminal](https://composal.com/product/cli) | ✓ Yes: Use the CLI to start and inspect verification runs and their Findings. | – With setup: Connect its specialist checks to your development workflow using supported integrations. |
| Source code review and analysis | × No: Use a dedicated tool for this specialist workflow alongside Composal’s browser verification. | ✓ Yes: ESLint is a pluggable JavaScript linter that analyzes code for problematic patterns and style rules. Teams configure core rules and add ecosystem plugins. |

With setup means you supply code or configuration. Not confirmed means support for this workflow needs checking with the vendor.

## Where each fits

Choose ESLint when JavaScript rules and editor or CI diagnostics are needed. Choose Composal for runtime browser QA and exploratory coverage. Keep ESLint in place for its configured code checks.

## Try this evaluation

Add or retain representative ESLint rules in CI and change a related browser flow. Compare diagnostics with Composal’s execution result; use the pilot to distinguish style or pattern violations from broken user outcomes.

### Coverage

Which user outcomes must this release prove, and which specialist checks must stay in your existing stack?

### Setup

Who prepares accounts, test data, permissions and access to the deployment being tested?

### Evidence

Can the engineer reproduce a reported failure from the recording and steps, without asking the tester to investigate again?

### Ownership

Who updates the checks when the product changes, and can the team review what a passing result actually proves?

## Related comparisons

- [Composal vs Biome](https://composal.com/compare/composal-vs-biome.md)
- [Composal vs GitHub CodeQL](https://composal.com/compare/composal-vs-codeql.md)
- [Composal vs OWASP ZAP](https://composal.com/compare/composal-vs-owasp-zap.md)

[All comparisons](https://composal.com/compare.md)