Assert Regex Pattern Absent

Ensure a regex pattern does NOT match in the page HTML.

The Problem

The inverse of regex_match. Block deployment when pages contain patterns that should never appear: debug log formats, SQL fragments, internal API URLs, or PII patterns like unmasked emails.

The Hard Way

Same as regex_match but inverted. At scale, you need the same automation infrastructure.

The SEODiff Way

One API call. Results in under 2 seconds.

POST https://seodiff.io/api/v1/agent/evaluate

{"urls": ["https://example.com/landing/page-1"], "assertions": [{"rule": "regex_not_match", "value": "(?i)(debug|console\\\\.log|TODO)"}]}
ParameterTypeExample
valueregex(?i)(debug|console\.log|TODO)

Code Examples

Copy-paste examples in your preferred language:

cURL

See the full evaluation example in cURL →

Python

See the full evaluation example in Python →

Node.js

See the full evaluation example in Node.js →

Go

See the full evaluation example in Go →

PHP

See the full evaluation example in PHP →

Related Assertions

regex_match

Verify that a regex pattern matches somewhere in the page HTML.

not_contains_string

Ensure specific text does NOT appear in the rendered page.

no_placeholders

Find template variables like {{city}} or [TBD] that leaked into production HTML.

Use in CI/CD

Add this assertion to your deployment pipeline. Works with any CI platform:

🐙 GitHub Actions

Block bad deployments with automated SEO checks in your GitHub Actions CI/CD pipeline.

🦊 GitLab CI

Add automated SEO quality gates to your GitLab CI/CD pipelines.

▲ Vercel

Automatically validate SEO on every Vercel preview deployment before promoting to production.

Start testing in 30 seconds

Get an API key and run your first evaluation with a single cURL command.

Get API Key or Read full API docs