End-to-end (e2e) tests are tests that aim to simulate the user experience as closely as possible and will look almost like manual testing, but automated.
Although end-to-end tests are immensely valuable, itâs worth considering reasons why you might not want to write them:
- Theyâre slow to write and slow to run. Itâll take a lot of valuable engineering time to write out e2e tests, and itâll consume valuable seconds of a cloud CI server that youâre paying for.
- Theyâre often a lot more brittle than integration tests or unit tests, meaning that if your application requires some minor or major change, it might mean tweaking your e2e tests. This complicates software maintenance.
In general, only invest more resources into e2e tests when youâve extracted most of the value from the tests lower in the Agile âtesting pyramidâ:
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