What is "Shift Left" in DevOps, and why does it matter?

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Shift Left means moving activities like testing, security, and reliability checks earlier (to the left ) in the software development lifecycle, instead of treating them as last-minute steps before release. Examples: SAST / linting in the IDE or pre-commit hook. SCA (dependency scanning) in PR pipelines. IaC scanning (Checkov, tfsec) on Terraform PRs. Container image scanning in CI before pushing to registry. Performance / load tests in pre-prod, not after launch. Why it matters: bugs caught at the IDE cost ~10× less than in QA, and ~100× less than in production. Shift Left compresses feedback loops. Shift Left = pull testing, security, and reliability concerns to the *left* of the SDLC timeline (closer to dev). Mention concrete shifts: SAST in PR, IaC scanning in CI, chaos testing in staging. That shows you've actually done it.