Software Testing Evolution, Shift Left/Right, and Automation vs Test Automation

Recent hiring trends show a decline in dedicated test engineer positions in large internet companies, but software testing remains essential.

The article outlines the evolution of software testing through five periods: Debugging period, Demonstration period, Destruction period, Evaluation period, and Prevention period, citing historical milestones such as the 1947 "bug" incident and the 1979 definition by Glenford Myers.

It explains the concept of "testing shift left", moving verification activities earlier in the development lifecycle to catch defects sooner, and discusses why this approach improves quality, reduces costs, and aligns with agile practices.

Conversely, "testing shift right" refers to testing activities that occur after release, in production environments, emphasizing the need for observability, CX testing, and reliability engineering.

The article distinguishes between "automation testing" (automatically executing test cases) and "test automation" (automating the entire test management workflow), highlighting their different scopes and benefits.

Practical guidance includes using TDD, BDD, static analysis tools like ESLint, and integrating testing into CI/CD pipelines, as well as the challenges and limitations of left‑ and right‑shift testing.

Finally, the author shares personal reflections on the role of developers in quality assurance and encourages a culture where quality is everyone's responsibility.

Requirement →
Design →
Implementation →
Verification →
Maintenance