c/side vs @fastify/helmet: side-by-side comparison (2026)

c/side: Client-side platform securing browser scripts, detecting fraud & ensuring PCI compliance. Built by C/side.

@fastify/helmet: A Fastify plugin that implements HTTP security headers through a wrapper around the helmet library to protect web applications from common vulnerabilities.

The table above shows where their features, integrations, deployment and company size fit differ.

c/side is made by C/side. @fastify/helmet is open-source with 453 GitHub stars. The vendor behind a product decides its roadmap, support, and longevity, so check each company's profile before you commit.

Often, yes. c/side and @fastify/helmet are both Runtime Application Self-Protection products, and both cover Web Security. Key differences: c/side is Commercial while @fastify/helmet is Free, @fastify/helmet is open-source. Use the table above to see where features, deployment and company size fit differ.