Ask HN: Ed25519 or Curve25519 for long term identity?

Hi,<p>I&#x27;m currently developing an application using EC public key cryptography. However I&#x27;m a little bit confused by which kind of public key I should use for long term identity, Ed25519 or Curve25519.<p>As I understand, the curves are convertible ([0] &amp; [1]), so it&#x27;s not clear which one is better to use.<p>SSH and TLS use Ed25519 while Signal and NaCl use Curve25519.<p>Any pointer for which one should I use (or should NOT use)?<p>[0] https:&#x2F;&#x2F;curves.moderncrypto.narkive.com&#x2F;BMafwQ5i&#x2F;xeddsa-specification<p>[1] https:&#x2F;&#x2F;blog.filippo.io&#x2F;using-ed25519-keys-for-encryption&#x2F;