diff --git a/src/streamvbyte.cpp b/src/streamvbyte.cpp
index ca8c685..c9eebe4 100644
--- a/src/streamvbyte.cpp
+++ b/src/streamvbyte.cpp
@@ -25,6 +25,7 @@ PYBIND11_MODULE(libstreamvbyte, m) {
 
             return out;
         },
+        py::arg("in"),
         "Encode an array of unsigned integers into a byte array.");
 
     m.def(
@@ -42,6 +43,7 @@ PYBIND11_MODULE(libstreamvbyte, m) {
 
             return out;
         },
+        py::arg("in"), py::arg("size"),
         "Decode a byte array into an array of unsigned integers.");
 
     m.def(
@@ -59,6 +61,7 @@ PYBIND11_MODULE(libstreamvbyte, m) {
 
             return out;
         },
+        py::arg("in"),
         "Encode an array of signed integers into an array of unsigned integers.");
 
     m.def(
@@ -76,6 +79,7 @@ PYBIND11_MODULE(libstreamvbyte, m) {
 
             return out;
         },
+        py::arg("in"),
         "Decode an array of unsigned integers into an array of signed integers.");
 
     m.def(
diff --git a/tests/test.py b/tests/test.py
index e83bcea..5a51693 100644
--- a/tests/test.py
+++ b/tests/test.py
@@ -7,11 +7,11 @@
 def test_streamvbyte():
     original_data = np.random.randint(0, 2**32, N, dtype=np.uint32)
 
-    compressed_bytes = svb.encode(original_data)
+    compressed_bytes = svb.encode(in=original_data)
     assert type(compressed_bytes) == np.ndarray
     assert compressed_bytes.dtype == np.uint8
 
-    recovered_data = svb.decode(compressed_bytes, N)
+    recovered_data = svb.decode(in=compressed_bytes, size=N)
     assert type(recovered_data) == np.ndarray
     assert recovered_data.dtype == np.uint32
 
@@ -22,11 +22,11 @@ def test_streamvbyte():
 def test_zigzag():
     original_data = np.random.randint(-2**31, 2**31, N, dtype=np.int32)
 
-    encoded_unsigend_integers = svb.zigzag_encode(original_data)
+    encoded_unsigend_integers = svb.zigzag_encode(in=original_data)
     assert type(encoded_unsigend_integers) == np.ndarray
     assert encoded_unsigend_integers.dtype == np.uint32
 
-    recovered_data = svb.zigzag_decode(encoded_unsigend_integers)
+    recovered_data = svb.zigzag_decode(in=encoded_unsigend_integers)
     assert type(recovered_data) == np.ndarray
     assert recovered_data.dtype == np.int32
 
@@ -37,11 +37,15 @@ def test_zigzag():
 def test_integrate():
     original_data = np.random.randint(-2**31, 2**31, N, dtype=np.int32)
 
-    compressed_bytes = svb.encode(svb.zigzag_encode(original_data))
+    compressed_bytes = svb.encode(
+        in=svb.zigzag_encode(in=original_data)
+    )
     assert type(compressed_bytes) == np.ndarray
     assert compressed_bytes.dtype == np.uint8
 
-    recovered_data = svb.zigzag_decode(svb.decode(compressed_bytes, N))
+    recovered_data = svb.zigzag_decode(
+        in=svb.decode(in=compressed_bytes, size=N)
+    )
     assert type(recovered_data) == np.ndarray
     assert recovered_data.dtype == np.int32