For most teams, start with SCA, which checks your open source dependencies, because it is quick to set up and covers code you did not write. Add SAST for your own code next, then DAST for running applications. Your own risk profile can change that order.
What each one examines
SCA reads your dependency inventory and matches it to known vulnerabilities. Fast, low effort, low setup.
SAST analyses your source code without running it, looking for flaws such as injection and unsafe handling of input. Needs tuning to cut noise.
DAST tests a running application from the outside by sending requests. Finds issues that appear only at runtime, such as misconfiguration. Needs a deployed target and, for useful depth, authentication set up.
Why SCA tends to come first
Modern applications are mostly open source by volume. SCA covers that majority with a small effort, and fixes are usually a version bump. Quick wins build trust in the programme.
When to reorder
- You write a lot of custom code with sensitive logic, such as payments: bring SAST forward.
- You run a public web application with little code review: bring DAST forward.
- You were asked for a specific test by a customer or regulator: do that one first.
What each misses
SCA misses flaws in your own logic. SAST misses runtime and configuration issues and can miss flaws that span services. DAST sees only what it reaches, so poor coverage of authenticated pages gives false comfort. No single method is complete, and none replaces code review or threat modelling.
A staged plan
- Month 1: SCA on all repositories, with pull request checks.
- Month 2 to 3: SAST on the most critical services.
- Month 3 to 4: DAST against staging for internet facing apps.
Questions that settle the order
Ask three things. What do customers or auditors expect from us? Where would a breach hurt most, in our own logic or in third party code? And which method can we operate well with the people we have? A tool nobody has time to tune produces noise, so a smaller scope run well beats a broad scope run badly. Revisit the order each year.
Try it yourself
Click through it at your own pace, or open it full screen.
Look at the kind of finding SAST reports and compare it with a dependency finding.
Where Safeguard fits
Safeguard covers SBOM and dependency scanning, with a free scan to begin.
Quick check
Can one tool replace all three?
Some platforms bundle them, but each method still has its own strengths. Judge each on its own merits.
Last reviewed: 19 October 2026.
