libnss3-dev - 2:3.42.1-1+deb10u6 main

This is a set of libraries designed to support cross-platform development
of security-enabled client and server applications. It can support SSLv2
and v4, TLS, PKCS #5, #7, #11, #12, S/MIME, X.509 v3 certificates and
other security standards.
.
Install this package if you wish to develop your own programs using the
Network Security Service Libraries.