diff --git a/c_src/enacl_nif.c b/c_src/enacl_nif.c
index 1b154dc..da54551 100644
--- a/c_src/enacl_nif.c
+++ b/c_src/enacl_nif.c
@@ -641,6 +641,16 @@ ERL_NIF_TERM enif_crypto_secretbox_BOXZEROBYTES(ErlNifEnv *env, int argc, ERL_NI
 	return enif_make_int64(env, crypto_secretbox_BOXZEROBYTES);
 }
 
+static
+ERL_NIF_TERM enif_crypto_stream_chacha20_KEYBYTES(ErlNifEnv *env, int argc, ERL_NIF_TERM const argv[]) {
+	return enif_make_int64(env, crypto_stream_chacha20_KEYBYTES);
+}
+
+static
+ERL_NIF_TERM enif_crypto_stream_chacha20_NONCEBYTES(ErlNifEnv *env, int argc, ERL_NIF_TERM const argv[]) {
+	return enif_make_int64(env, crypto_stream_chacha20_NONCEBYTES);
+}
+
 static
 ERL_NIF_TERM enif_crypto_stream_KEYBYTES(ErlNifEnv *env, int argc, ERL_NIF_TERM const argv[]) {
 	return enif_make_int64(env, crypto_stream_KEYBYTES);
@@ -756,6 +766,61 @@ ERL_NIF_TERM enif_crypto_secretbox_open(ErlNifEnv *env, int argc, ERL_NIF_TERM c
 	    padded_ciphertext.size - crypto_secretbox_ZEROBYTES);
 }
 
+static
+ERL_NIF_TERM enif_crypto_stream_chacha20(ErlNifEnv *env, int argc, ERL_NIF_TERM const argv[]) {
+	ErlNifBinary c, n, k;
+	ErlNifUInt64 clen;
+
+	if (
+	  (argc != 3) ||
+	  (!enif_get_uint64(env, argv[0], &clen)) ||
+	  (!enif_inspect_binary(env, argv[1], &n)) ||
+	  (!enif_inspect_binary(env, argv[2], &k))) {
+		return enif_make_badarg(env);
+	}
+
+	if (
+	  (k.size != crypto_stream_chacha20_KEYBYTES) ||
+	  (n.size != crypto_stream_chacha20_NONCEBYTES)) {
+		return enif_make_badarg(env);
+	}
+
+	if (!enif_alloc_binary(clen, &c)) {
+		return nacl_error_tuple(env, "alloc_failed");
+	}
+
+	crypto_stream_chacha20(c.data, c.size, n.data, k.data);
+
+	return enif_make_binary(env, &c);
+}
+
+static
+ERL_NIF_TERM enif_crypto_stream_chacha20_xor(ErlNifEnv *env, int argc, ERL_NIF_TERM const argv[]) {
+	ErlNifBinary c, m, n, k;
+
+	if (
+	  (argc != 3) ||
+	  (!enif_inspect_iolist_as_binary(env, argv[0], &m)) ||
+	  (!enif_inspect_binary(env, argv[1], &n)) ||
+	  (!enif_inspect_binary(env, argv[2], &k))) {
+		return enif_make_badarg(env);
+	}
+
+	if (
+	  (k.size != crypto_stream_chacha20_KEYBYTES) ||
+	  (n.size != crypto_stream_chacha20_NONCEBYTES)) {
+		return enif_make_badarg(env);
+	}
+
+	if (!enif_alloc_binary(m.size, &c)) {
+		return nacl_error_tuple(env, "alloc_failed");
+	}
+
+	crypto_stream_chacha20_xor(c.data, m.data, m.size, n.data, k.data);
+
+	return enif_make_binary(env, &c);
+}
+
 static
 ERL_NIF_TERM enif_crypto_stream(ErlNifEnv *env, int argc, ERL_NIF_TERM const argv[]) {
 	ErlNifBinary c, n, k;
@@ -1071,6 +1136,13 @@ static ErlNifFunc nif_funcs[] = {
 	{"crypto_secretbox_open_b", 3, enif_crypto_secretbox_open},
 	{"crypto_secretbox_open", 3, enif_crypto_secretbox_open, ERL_NIF_DIRTY_JOB_CPU_BOUND},
 
+	{"crypto_stream_chacha20_KEYBYTES", 0, enif_crypto_stream_chacha20_KEYBYTES},
+	{"crypto_stream_chacha20_NONCEBYTES", 0, enif_crypto_stream_chacha20_NONCEBYTES},
+	{"crypto_stream_chacha20_b", 3, enif_crypto_stream_chacha20},
+	{"crypto_stream_chacha20", 3, enif_crypto_stream_chacha20, ERL_NIF_DIRTY_JOB_CPU_BOUND},
+	{"crypto_stream_chacha20_xor_b", 3, enif_crypto_stream_chacha20_xor},
+	{"crypto_stream_chacha20_xor", 3, enif_crypto_stream_chacha20_xor, ERL_NIF_DIRTY_JOB_CPU_BOUND},
+
 	{"crypto_stream_KEYBYTES", 0, enif_crypto_stream_KEYBYTES},
 	{"crypto_stream_NONCEBYTES", 0, enif_crypto_stream_NONCEBYTES},
 	{"crypto_stream_b", 3, enif_crypto_stream},
diff --git a/src/enacl.erl b/src/enacl.erl
index 0244152..5e06dc8 100644
--- a/src/enacl.erl
+++ b/src/enacl.erl
@@ -49,6 +49,11 @@
 	secretbox/3,
 	secretbox_open/3,
 
+	stream_chacha20_key_size/0,
+	stream_chacha20_nonce_size/0,
+	stream_chacha20/3,
+	stream_chacha20_xor/3,
+
 	stream_key_size/0,
 	stream_nonce_size/0,
 	stream/3,
@@ -129,6 +134,8 @@
 -define(S_ZEROBYTES, <<0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0>>). %% 32 bytes
 -define(CRYPTO_SECRETBOX_BOXZEROBYTES, 16).
 -define(S_BOXZEROBYTES, <<0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0>>). %% 16 bytes
+-define(CRYPTO_STREAM_CHACHA20_KEYBYTES, 32).
+-define(CRYPTO_STREAM_CHACHA20_NONCEBYTES, 8).
 -define(CRYPTO_STREAM_KEYBYTES, 32).
 -define(CRYPTO_STREAM_NONCEBYTES, 24).
 
@@ -141,6 +148,8 @@ verify() ->
     	?S_BOXZEROBYTES),
     
     Verifiers = [
+        {crypto_stream_chacha20_KEYBYTES, ?CRYPTO_STREAM_CHACHA20_KEYBYTES},
+        {crypto_stream_chacha20_NONCEBYTES, ?CRYPTO_STREAM_CHACHA20_NONCEBYTES},
         {crypto_stream_KEYBYTES, ?CRYPTO_STREAM_KEYBYTES},
         {crypto_stream_NONCEBYTES, ?CRYPTO_STREAM_NONCEBYTES},
         {crypto_box_ZEROBYTES, ?CRYPTO_BOX_ZEROBYTES},
@@ -501,6 +510,63 @@ secretbox_nonce_size() ->
 secretbox_key_size() ->
     enacl_nif:crypto_secretbox_KEYBYTES().
 
+%% @doc stream_chacha20_nonce_size/0 returns the byte size of the nonce for streams
+%% @end
+-spec stream_chacha20_nonce_size() -> pos_integer().
+stream_chacha20_nonce_size() -> ?CRYPTO_STREAM_CHACHA20_NONCEBYTES.
+
+%% @doc stream_key_size/0 returns the byte size of the key for streams
+%% @end
+-spec stream_chacha20_key_size() -> pos_integer().
+stream_chacha20_key_size() -> ?CRYPTO_STREAM_CHACHA20_KEYBYTES.
+
+%% @doc stream_chacha20/3 produces a cryptographic stream suitable for secret-key encryption
+%%
+%% <p>Given a positive `Len' a `Nonce' and a `Key', the stream_chacha20/3 function will return an unpredictable cryptographic stream of bytes
+%% based on this output. In other words, the produced stream is indistinguishable from a random stream. Using this stream one
+%% can XOR it with a message in order to produce a encrypted message.</p>
+%% <p><b>Note:</b>  You need to use different Nonce values for different messages. Otherwise the same stream is produced and thus
+%% the messages will have predictability which in turn makes the encryption scheme fail.</p>
+%% @end
+-spec stream_chacha20(Len, Nonce, Key) -> CryptoStream
+  when
+    Len :: non_neg_integer(),
+    Nonce :: binary(),
+    Key :: binary(),
+    CryptoStream :: binary().
+stream_chacha20(Len, Nonce, Key) when is_integer(Len), Len >= 0, Len =< ?STREAM_SIZE ->
+    bump(enacl_nif:crypto_stream_chacha20_b(Len, Nonce, Key),
+         ?STREAM_REDUCTIONS,
+         ?STREAM_SIZE,
+         Len);
+stream_chacha20(Len, Nonce, Key) when is_integer(Len), Len >= 0 ->
+    enacl_nif:crypto_stream_chacha20(Len, Nonce, Key);
+stream_chacha20(_, _, _) -> error(badarg).
+
+%% @doc stream_chacha20_xor/3 encrypts a plaintext message into ciphertext
+%%
+%% The stream_chacha20_xor/3 function works by using the {@link stream_chacha20/3} api to XOR a message with the cryptographic stream. The same
+%% caveat applies: the nonce must be new for each sent message or the system fails to work.
+%% @end
+-spec stream_chacha20_xor(Msg, Nonce, Key) -> CipherText
+  when
+    Msg :: iodata(),
+    Nonce :: binary(),
+    Key :: binary(),
+    CipherText :: binary().
+stream_chacha20_xor(Msg, Nonce, Key) ->
+    case iolist_size(Msg) of
+      K when K =< ?STREAM_SIZE ->
+        bump(enacl_nif:crypto_stream_chacha20_xor_b(Msg, Nonce, Key),
+             ?STREAM_REDUCTIONS,
+             ?STREAM_SIZE,
+             K);
+      _ ->
+        enacl_nif:crypto_stream_chacha20_xor(Msg, Nonce, Key)
+    end.
+
+%% @doc auth_key_size/0 returns the byte-size of the authentication key
+%% @end
 %% @doc stream_nonce_size/0 returns the byte size of the nonce for streams
 %% @end
 -spec stream_nonce_size() -> pos_integer().
diff --git a/src/enacl_nif.erl b/src/enacl_nif.erl
index d18c2c0..36ab1d1 100644
--- a/src/enacl_nif.erl
+++ b/src/enacl_nif.erl
@@ -52,6 +52,14 @@
 	crypto_secretbox_open/3,
 	crypto_secretbox_open_b/3,
 
+	crypto_stream_chacha20_KEYBYTES/0,
+	crypto_stream_chacha20_NONCEBYTES/0,
+
+	crypto_stream_chacha20/3,
+	crypto_stream_chacha20_b/3,
+	crypto_stream_chacha20_xor/3,
+	crypto_stream_chacha20_xor_b/3,
+
 	crypto_stream_KEYBYTES/0,
 	crypto_stream_NONCEBYTES/0,
 
@@ -168,6 +176,13 @@ crypto_secretbox_b(_Msg, _Nonce, _Key) -> erlang:nif_error(nif_not_loaded).
 crypto_secretbox_open(_Msg, _Nonce, _Key) -> erlang:nif_error(nif_not_loaded).
 crypto_secretbox_open_b(_Msg, _Nonce, _Key) -> erlang:nif_error(nif_not_loaded).
 
+crypto_stream_chacha20_KEYBYTES() -> erlang:nif_error(nif_not_loaded).
+crypto_stream_chacha20_NONCEBYTES() -> erlang:nif_error(nif_not_loaded).
+crypto_stream_chacha20(_Bytes, _Nonce, _Key) -> erlang:nif_error(nif_not_loaded).
+crypto_stream_chacha20_b(_Bytes, _Nonce, _Key) -> erlang:nif_error(nif_not_loaded).
+crypto_stream_chacha20_xor(_M, _Nonce, _Key) -> erlang:nif_error(nif_not_loaded).
+crypto_stream_chacha20_xor_b(_M, _Nonce, _Key) -> erlang:nif_error(nif_not_loaded).
+
 crypto_stream_KEYBYTES() -> erlang:nif_error(nif_not_loaded).
 crypto_stream_NONCEBYTES() -> erlang:nif_error(nif_not_loaded).
 crypto_stream(_Bytes, _Nonce, _Key) -> erlang:nif_error(nif_not_loaded).