Including the very, very limited environment of secure elements, and the capability of interfacing with the sometimes very specialized cryptographic accelerators/coprocessors required for adequate performance?
We're talking low double-digit kilobytes of persistent storage, and sometimes single-digit kilobytes of memory here.
Also, including a full TLS library seems like complete overkill if you only need some cryptographic primitives. These things are usually certified in expensive code and hardware audits; you essentially have to justify (in terms of adding complexity, and with it the possibility of vulnerabilities) and on top of that pay for every single line of code.
We're talking low double-digit kilobytes of persistent storage, and sometimes single-digit kilobytes of memory here.
Also, including a full TLS library seems like complete overkill if you only need some cryptographic primitives. These things are usually certified in expensive code and hardware audits; you essentially have to justify (in terms of adding complexity, and with it the possibility of vulnerabilities) and on top of that pay for every single line of code.