Manual testing is a person checking the software by hand; automated testing is code that checks it for you, on every change, in seconds. Manual testing is good at judging whether something feels right. Automated testing is good at proving, over and over, that what worked yesterday still works today. Most teams reach a point where releases slow down because someone has to click through the app before every deploy, and that is usually when a QA automation engineer becomes worth bringing in. This guide compares the two and covers the signs you have reached it.
Manual vs automated testing compared
| Manual testing | Automated testing | |
|---|---|---|
| Who runs it | A person, by hand | Your CI pipeline, on every pull request |
| Cost of one more run | The same as the last one | Close to nothing |
| Good at | Exploring, judging usability, spotting the unexpected | Catching regressions, checking the same paths every time |
| Weak at | Repetition: attention fades on the fortieth run | Anything nobody thought to write a test for |
| Grows with the product by | Adding people or time | Adding tests |
The two are not rivals. Exploratory testing by someone who knows the product finds problems no script would look for. But regression testing, which is checking that the existing features still work, is the part that grows with every release, and it is the part automation does better.
What a QA automation engineer does
A QA automation engineer writes and maintains automated tests: end-to-end tests that drive the app the way a user would, API tests, and integration tests between services. They use frameworks such as Playwright, Cypress or Selenium, and they wire the tests into your CI pipeline so that every pull request runs them before it can merge.
The maintenance half of that job matters as much as the writing half. A test suite that fails at random teaches the team to ignore it, and a suite nobody trusts is worse than none, because it costs time and catches nothing. A good automation engineer treats a flaky test as a bug.
Signs you need a QA automation engineer
- Releases wait on someone clicking through the app. If a deploy cannot go out until a person has checked the checkout flow by hand, the release cadence is set by that person's calendar.
- The same bugs come back. A regression that was fixed once and reappeared is exactly what an automated test prevents.
- Developers are afraid to change old code. Without tests, nobody knows what a change will break, so nobody changes it.
- Your developers write unit tests, but nobody owns the end-to-end ones. Unit tests check functions; end-to-end tests check that a customer can actually sign up and pay.
- Bugs reach customers before your team sees them.
Where to start
Do not try to automate everything. Start with the one user journey that would cost you the most if it broke, usually sign-up, checkout or whatever your customers pay you for, and cover it with end-to-end tests that run on every pull request. That is a concrete first deliverable you can write into an SOW, and it pays off on the next release.
From there, add a test whenever a bug is fixed, so the same bug cannot come back, and widen coverage to the next most important journey.
Mid-level or senior
Choose senior if nobody on your team will set the testing strategy or review the tests: a senior engineer has owned this kind of work alone before. Choose mid-level if a senior developer on your team will decide what to test and review the work.
Frequently asked questions
Can automated testing replace manual testing completely?
No. Automation proves that known paths still work. A person exploring the product finds the problems nobody thought to test for, and judges whether something is confusing rather than broken. Most teams automate regression testing and keep a little exploratory testing.
Should developers write the tests themselves?
Developers should write unit tests for their own code. End-to-end tests across the whole product tend to go unwritten when they are everyone's job, which is why many teams give them an owner.
Which test framework is best?
Playwright, Cypress and Selenium all work. The right one is usually the one that fits your stack and that your team will maintain. Name the framework you use when you describe the role.
Do you place manual testers?
No. We place QA automation engineers, who write and maintain automated tests. Manual testing is not offered.
Where to go from here
sourceBOLD engages mid-level and senior QA automation engineers across the Americas, month to month, as their contractor of record. They work in your tools, alongside your developers, and the tests they write are yours (MSA §3). QA automation shows typical starting prices, and how we vet candidates covers what happens before you meet anyone.