OpenSSL
TLS and cryptography toolkit underpinning HTTPS, SSH adjacency, and certificate workflows.
Why it is included
Foundational library with coordinated disclosure culture despite historic complexity.
Best for
Every engineer touching certs, TLS debugging, or crypto primitives.
If you use Windows, Mac, or paid tools
TLS/crypto building block alternative to proprietary FIPS modules and Windows SCHANNEL-only integrations (varies by app).
Strengths
- Ubiquity
- Protocol coverage
- Tooling
Limitations
- API ergonomics historically criticized
Good alternatives
LibreSSL · BoringSSL (not FOSS)
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