diff --git a/.spi.yml b/.spi.yml
index f84c610c..f07df006 100644
--- a/.spi.yml
+++ b/.spi.yml
@@ -1,4 +1,4 @@
 version: 1
 builder:
   configs:
-    - documentation_targets: [Crypto]
+    - documentation_targets: [Crypto, _CryptoExtras]
diff --git a/Sources/Crypto/Docs.docc/index.md b/Sources/Crypto/Docs.docc/index.md
new file mode 100644
index 00000000..e44b543b
--- /dev/null
+++ b/Sources/Crypto/Docs.docc/index.md
@@ -0,0 +1,12 @@
+# ``Crypto``
+
+A cryptography library for Swift.
+
+## Overview
+
+Swift Crypto provides a Swift library for common cryptographic operations. It is available as a Swift package and provides two main libraries:
+
+* `Crypto` - an open-source implementation of a substantial portion of the API of [Apple CryptoKit](https://developer.apple.com/documentation/cryptokit) suitable for use on Linux platforms. It enables cross-platform or server applications with the advantages of CryptoKit.
+* `CryptoExtras` - a collection of additional cryptographic primitives and utilities that are not part of CryptoKit but useful in a server environment.
+
+Swift Crypto is built on top of [BoringSSL](https://boringssl.googlesource.com/boringssl/), Google's fork of OpenSSL. The current features of Swift Crypto cover key exchange, key derivation, encryption and decryption, hashing, message authentication, and more.
\ No newline at end of file
diff --git a/Sources/_CryptoExtras/Docs.docc/index.md b/Sources/_CryptoExtras/Docs.docc/index.md
new file mode 100644
index 00000000..310cf0dd
--- /dev/null
+++ b/Sources/_CryptoExtras/Docs.docc/index.md
@@ -0,0 +1,5 @@
+# ``CryptoExtras``
+
+Provides additional cryptographic APIs that are not available in CryptoKit (and therefore the core Crypto library).
+
+