Free vs paid security scanning tools for small development teams

What you actually get for free

Security tooling has a weird relationship with money. Some genuinely excellent tools are free. Some expensive ones are surprisingly shallow. And a lot of the "free tier" offerings exist mainly to funnel you toward a sales call.

Let me try to cut through that.

If you are a small team, probably without a dedicated security engineer, here is the honest picture.

The free tools worth knowing

Semgrep (free tier) is probably the most capable free static analysis tool available right now. The open-source rules are solid, the CLI is fast, and you can write custom rules if you are willing to spend an afternoon on it. The catch: the free tier does not include secrets detection, supply chain scanning, or the managed dashboard. You get a powerful engine without much of the reporting layer.

Gitleaks is excellent for one specific job: scanning your git history for secrets that should never have been committed. It is free, open source, and genuinely good at what it does. Run it once on any old repo and prepare to wince.

gitleaks detect --source . --verbose

npm audit and pip-audit handle dependency vulnerability scanning for their respective ecosystems. They are free because they are bundled with the package managers. They are also narrow: they only see declared dependencies, they do not reason about how those dependencies are used, and they tell you nothing about your application code.

Trivy from Aqua Security covers container image scanning, infrastructure as code, and dependency scanning, all free and open source. For teams shipping Docker images, Trivy is almost mandatory. The question is whether you have the time to wire it into CI and act on its output.

Where free tools fall short

Here is the uncomfortable truth: free tools are almost always excellent at one specific thing and silent about everything else.

Gitleaks will not tell you that your Express app has no rate limiting. Semgrep will not notice that your S3 bucket policy is public. Trivy will not flag that you are running a container as root without a read-only filesystem. Each tool has a clearly bounded scope, and the boundaries rarely align with how attackers actually think about your application.

There is also the integration problem. Wiring five separate free tools into your CI pipeline, normalising their outputs, deciding which findings block merges and which do not, and keeping rules updated across all of them, is real work. For a team of two or three people, that overhead quietly kills the initiative. The tools get added to .github/workflows, produce a wall of JSON, and then nobody looks at them after the first month.

What paid tools offer

Paid tools generally do one of two things: they provide a managed version of something that was already free (Semgrep Pro is essentially this), or they cover a genuinely broader surface area than any free tool.

The managed offerings are worth considering if your main problem is operational: you want dashboards, trend tracking, policy enforcement across repos, and someone else handling rule updates. Semgrep Pro, Snyk, and Sonar all fit this pattern. Prices range from roughly $20 to $50 per developer per month for teams, which adds up fast.

The broader-surface tools tend to include things like:

• Runtime analysis alongside static scanning
• Business logic checks that require understanding your specific stack
• Compliance mapping (SOC 2, PCI, ISO 27001)
• Integrated remediation suggestions from an LLM

Whether any of that justifies the cost depends entirely on your situation. A three-person startup building an internal tool has different needs than a five-person team processing payment data.

A framework for deciding

Before spending money, answer these questions honestly.

First: do you have someone who will actually look at findings and fix them? No tool, paid or free, helps if findings accumulate unread. If the answer is no, start there rather than with tooling.

Second: what is your actual threat model? If you are mostly worried about accidentally committing API keys, Gitleaks is free and solves that. If you are worried about your Docker containers having exploitable CVEs, Trivy is free and solves that. You do not need a $400/month platform for a focused problem.

Third: is your main bottleneck scanning quality or operational overhead? If you already run three free tools but nobody monitors them, paying for a managed platform might genuinely help. If you do not run anything yet, start free and see what you actually pay attention to.

Where a tool like Seaworthy fits

Seaworthy occupies a specific niche in this space. It is designed for solo developers and small teams who use AI-assisted development and want a fast, opinionated scan of a repo without a lengthy setup process. You run npx seaworthycode in a project directory and get a report covering security, resilience, ops basics, dependency hygiene, configuration issues, and data exposure, in one pass.

The free tier covers basic checks. Pro (£2.99/mo) adds a broader set of checks including things like missing rate limiting, insecure session configuration, and secrets in environment files that have been accidentally committed. It is not a replacement for Semgrep or Trivy in a mature CI pipeline. It is more useful earlier, when you want to know what category of problems exists before you have decided which specialised tools to deploy.

There is no single right answer here. The right tool is the one your team will actually run and act on. Start with that constraint and work backwards from it.

Seaworthy is available via npx seaworthycode or as a VS Code extension.