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+## Stream Ciphers
+
+> **See also**: [Libsodium's documentation on its stream cipher features](https://download.libsodium.org/doc/advanced/stream_ciphers/xsalsa20).
+
+### crypto_stream
+
+Obtain an arbitrary-length stream of pseudorandom bytes from a given 
+nonce and key.
+
+**Parameters and their respective types**:
+
+1. `{number}` length
+2. `{Buffer}` nonce (must be 24 bytes)
+3. `{CryptographyKey}` key
+
+Returns a `Promise` that resolves to a `Buffer` containing
+the pseudorandom bytes.
+
+### crypto_stream_xor
+
+Encrypt a message with a given nonce and key.
+
+> [**Danger: Unauthenticated encryption!**](https://tonyarcieri.com/all-the-crypto-code-youve-ever-written-is-probably-broken)
+> Without a subsequent message authentication strategy, this is vulnerable to
+> chosen-ciphertext attacks. Proceed with caution!
+
+**Parameters and their respective types**:
+
+1. `{string|Buffer}` plaintext
+2. `{Buffer}` nonce (must be 24 bytes)
+3. `{CryptographyKey}` key
+
+Returns a `Promise` that resolves to a `Buffer` containing
+the encrypted bytes.
+
+### Example for crypto_stream
+
+```javascript
+const { SodiumPlus } = require('sodium-plus');
+
+let sodium;
+(async function () {
+    if (!sodium) sodium = await SodiumPlus.auto();
+    let key = await sodium.crypto_stream_keygen();
+    let iv = await sodium.randombytes_buf(24);
+    let output = await sodium.crypto_stream(64, iv, key);
+    console.log(output);
+
+    iv = await sodium.randombytes_buf(24);
+    let plaintext = 'This is a secret message';
+    let ciphertext = await sodium.crypto_stream_xor(plaintext, iv, key);
+    let decrypted =  await sodium.crypto_stream_xor(ciphertext, iv, key);
+    console.log(decrypted.toString());
+})();
+```