a README.

README.md

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+sn-sha256
+=========
+
+A SHA256 implementation in C for use in Scala 3 Native.
+
+Installation
+------------
+
+```sbt
+libraryDependencies += "com.fiatjaf" %%% "sn-sha256" % "0.2.0"
+```
+
+Usage
+-----
+
+This library provides a single `sha256()` function that takes either a `String` or an `Array[UByte]` and outputs an `Array[UByte]`.
+
+```scala
+import scala.scalanative.unsigned._
+import sha256.Sha256.sha256
+
+sha256("a string")
+// ==> Array[UByte](192, 220, 134, 239, 218, 0, 96, 212, 8, 64, 152, 169, 14, 201, 43, 61, 74, 168, 157, 127, 126, 15, 186, 84, 36, 86, 29, 33, 69, 30, 23, 88)
+
+sha256(Array[UByte](12.toUByte, 23.toUByte, 244.toUByte, 180.toUByte))
+  .map(_.toHexString)
+  .map(x => if (x.size == 2) x else s"0$x")
+  .mkString
+// ==> "c8010c6ca931acf480fab946f52d6abf81de50f797a666017cb4f0347c0974f9"
+```