Alright, let's get this out of the way before the hype train runs me over. We mandated Semgrep for our entire engineering org 12 months ago. The pitch was irresistible: shift-left, catch bugs early, free tier, yada yada. After a year of wrestling with it in production, here's the unvarnished, somewhat painful truth.
The good is actually quite good. The rule syntax is genuinely accessible. We got junior security engineers writing meaningful rules within a week, something that would have been a multi-month investment for a custom Checkov module or mastering CodeQL's arcane structures. The ability to run it locally as a pre-commit hook or in CI with a simple Docker command is a legitimate win. We've caught a staggering number of hardcoded credentials, misconfigured S3 bucket ACLs, and unsafe deserialization patterns before they ever hit a PR. For the classic, pattern-matchable vulnerabilities, it's effective.
```yaml
rules:
- id: aws-efs-encryption-disabled
patterns:
- pattern: |
new FileSystem(...){
...
Encrypted: false,
...
}
message: EFS file system is not encrypted at rest.
languages: [typescript]
severity: ERROR
```
But here's where my cynical ops heart starts to ache. The noise. Oh, the noise. The default rule packs (like "r2c-security-audit") are a blunt instrument. They generate a flood of findings, many of which are trivial or contextually irrelevant. We spent more time tuning and suppressing rules than we initially did writing them. The "value" metric touted by Semgrep Cloud Platform (SCP) feels like a vanity metric designed to please managers, not improve security posture. You quickly learn that a 10% "fix rate" on low-severity, auto-formattable findings is not a victory.
The real cost isn't the license for SCP (though that's not cheap at scale). It's the engineering time spent on triage and the relational debt incurred when you dump hundreds of "critical" findings from a generic rule pack on a team's backlog. We had to build an entire curation and prioritization layer on top of their API to make it palatable. And let's talk about the false sense of security. It's *only* a pattern matcher. Business logic flaws, complex authz bypasses? Not a chance. You'll miss the forest for the trees if you think Semgrep alone constitutes a SAST program.
So, would I do it again? Cautiously, yes. But with a very different approach: start with an empty rule set, never enable a community rule without peer review, and integrate it as a *supplement* to other tools, not the cornerstone. It's a useful grep on steroids, not a security silver bullet. Treat it as such, or prepare for burnout and ignored alerts.
-- cynical ops
Your k8s cluster is 40% idle.