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+# go-keypairs
+
+The lightest touch over top of Go's `crypto/ecdsa` and `crypto/rsa` to make them
+*typesafe* and to provide JSON Web Key (JWK) support.
+
+# Documentation
+
+Use the source, Luke!
+
+<https://godoc.org/github.com/big-squid/go-keypairs>
+
+# Philosophy
+
+Always remember:
+
+> Don't roll your own crypto.
+
+But also remember:
+
+> Just because you _don't_ know someone doesn't make them smart.
+
+Don't get the two mixed up!
+
+(furthermore, [just because you _do_ know someone doesn't make them _not_ smart](https://www.humancondition.com/asid-prophets-without-honour-in-their-own-home/))
+
+Although I would not want to invent my own cryptographic algorithm,
+I've read enough source code to know that, for standards I know well,
+I feel much more confident in the security, extensibility, and documentation
+of tooling that I've write myself.
+
+# Type Safety
+
+Go has _excellent_ crytography support and provides wonderful
+primitives for dealing with them. Its Achilles' heel is they're **not typesafe**!
+
+As of Go 1.11.5 `crypto.PublicKey` and `crypto.PrivateKey` are "marker interfaces"
+or, in other words, empty interfaces that only serve to document intent without
+actually providing a constraint to the type system.
+
+go-keypairs defines `type keypairs.PrivateKey interface { Public() crypto.PublicKey }`,
+which is implemented by `crypto/rsa` and `crypto/ecdsa`
+(but not `crypto/dsa`, which we really don't care that much about).
+
+Since there are no common methods between `rsa.PublicKey` and `ecdsa.PublicKey`,
+go-keypairs lightly wraps each to implement `Thumbprint() string` (part of the JOSE/JWK spec).
+
+# JSON Web Key "codec"
+
+Although there are many, many ways that JWKs could be interpreted
+(possibly why they haven't made it into the standard library), go-keypairs
+follows the basic pattern of `encoding/x509` to Parse and Marshal
+only the most basic and most meaningful parts of a key.
+
+I highly recommend that you use `Thumbprint()` for `KeyID` you also
+get the benefit of not losing information when encoding and decoding
+between the ASN.1, x509, PEM, and JWK formats.