diff --git a/include/webfuse/adapter/client_credentials.h b/include/webfuse/adapter/client_credentials.h
deleted file mode 100644
index f673317..0000000
--- a/include/webfuse/adapter/client_credentials.h
+++ /dev/null
@@ -1,28 +0,0 @@
-#ifndef WF_ADAPTER_CLIENT_CREDENTIALS_H
-#define WF_ADAPTER_CLIENT_CREDENTIALS_H
-
-#include "webfuse/adapter/api.h"
-
-#ifdef __cplusplus
-extern "C"
-{
-#endif
-
-struct wf_client_credentials;
-
-extern WF_API void
-wf_client_credentials_set_type(
-    struct wf_client_credentials * credentials,
-    char const * type);
-
-extern WF_API void
-wf_client_credentials_add(
-    struct wf_client_credentials * credentials,
-    char const * key,
-    char const * value);
-
-#ifdef __cplusplus
-}
-#endif
-
-#endif
diff --git a/include/webfuse/adapter/credentials.h b/include/webfuse/adapter/credentials.h
index e3e65fc..ca404f7 100644
--- a/include/webfuse/adapter/credentials.h
+++ b/include/webfuse/adapter/credentials.h
@@ -65,6 +65,28 @@ extern WF_API char const * wf_credentials_get(
     struct wf_credentials const * credentials,
     char const * key);
 
+//------------------------------------------------------------------------------
+/// \brief Sets the type of the credentials.
+///
+/// \param credentials Pointer to credentials object.
+/// \param type Type of credentials.
+//------------------------------------------------------------------------------
+extern WF_API void wf_credentials_set_type(
+    struct wf_credentials * credentials,
+    char const * type);
+
+//------------------------------------------------------------------------------
+/// \brief Adds an item to credentials
+///
+/// \param credentials Pointer to credentials object.
+/// \param key String to identify the item.
+/// \param key Value of the item.
+//------------------------------------------------------------------------------
+extern WF_API void wf_credentials_add(
+    struct wf_credentials * credentials,
+    char const * key,
+    char const * value);
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/include/webfuse_adapter.h b/include/webfuse_adapter.h
index da9533c..954f988 100644
--- a/include/webfuse_adapter.h
+++ b/include/webfuse_adapter.h
@@ -18,7 +18,6 @@
 #include <webfuse/adapter/mountpoint.h>
 
 #include <webfuse/adapter/client.h>
-#include <webfuse/adapter/client_credentials.h>
 
 
 #endif
diff --git a/lib/webfuse/adapter/api.c b/lib/webfuse/adapter/api.c
index 66288e6..613aaf7 100644
--- a/lib/webfuse/adapter/api.c
+++ b/lib/webfuse/adapter/api.c
@@ -147,6 +147,21 @@ char const * wf_credentials_get(
     return wf_impl_credentials_get(credentials, key);
 }
 
+void wf_credentials_set_type(
+    struct wf_credentials * credentials,
+    char const * type)
+{
+    wf_impl_credentials_set_type(credentials, type);
+}
+
+void wf_credentials_add(
+    struct wf_credentials * credentials,
+    char const * key,
+    char const * value)
+{
+    wf_impl_credentials_add(credentials, key, value);
+}
+
 // mountpoint
 
 struct wf_mountpoint *
@@ -255,24 +270,3 @@ wf_client_add_filesystem(
     (void) name;
 }
 
-// client credentials
-
-void
-wf_client_credentials_set_type(
-    struct wf_client_credentials * credentials,
-    char const * type)
-{
-    (void) credentials;
-    (void) type;
-}
-
-void
-wf_client_credentials_add(
-    struct wf_client_credentials * credentials,
-    char const * key,
-    char const * value)
-{
-    (void) credentials;
-    (void) key;
-    (void) value;
-}
\ No newline at end of file
diff --git a/lib/webfuse/adapter/impl/credentials.c b/lib/webfuse/adapter/impl/credentials.c
index 040638a..d4c9461 100644
--- a/lib/webfuse/adapter/impl/credentials.c
+++ b/lib/webfuse/adapter/impl/credentials.c
@@ -1,6 +1,13 @@
 #include "webfuse/adapter/impl/credentials.h"
 #include <string.h>
 
+void wf_impl_credentials_init_default(
+    struct wf_credentials * credentials)
+{
+    credentials->type = NULL;
+    credentials->data = json_object();
+}
+
 void wf_impl_credentials_init(
     struct wf_credentials * credentials,
     char const * type,
@@ -38,3 +45,20 @@ char const * wf_impl_credentials_get(
 
     return result;
 }
+
+void wf_impl_credentials_set_type(
+    struct wf_credentials * credentials,
+    char const * type)
+{
+    free(credentials->type);
+    credentials->type = strdup(type);
+}
+
+void wf_impl_credentials_add(
+    struct wf_credentials * credentials,
+    char const * key,
+    char const * value)
+{
+    json_object_set_new(credentials->data, key, json_string(value));
+}
+
diff --git a/lib/webfuse/adapter/impl/credentials.h b/lib/webfuse/adapter/impl/credentials.h
index a2cd647..59b4c0c 100644
--- a/lib/webfuse/adapter/impl/credentials.h
+++ b/lib/webfuse/adapter/impl/credentials.h
@@ -19,6 +19,9 @@ extern void wf_impl_credentials_init(
     char const * type,
     json_t * data);
 
+extern void wf_impl_credentials_init_default(
+    struct wf_credentials * credentials);
+
 extern void wf_impl_credentials_cleanup(
     struct wf_credentials * credentials);
 
@@ -29,6 +32,15 @@ extern char const * wf_impl_credentials_get(
     struct wf_credentials const * credentials,
     char const * key);
 
+extern void wf_impl_credentials_set_type(
+    struct wf_credentials * credentials,
+    char const * type);
+
+extern void wf_impl_credentials_add(
+    struct wf_credentials * credentials,
+    char const * key,
+    char const * value);
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/test/webfuse/tests/adapter/test_client.cc b/test/webfuse/tests/adapter/test_client.cc
index d972447..d64e57b 100644
--- a/test/webfuse/tests/adapter/test_client.cc
+++ b/test/webfuse/tests/adapter/test_client.cc
@@ -1,7 +1,7 @@
 #include <gtest/gtest.h>
 
 #include "webfuse/adapter/client.h"
-#include "webfuse/adapter/client_credentials.h"
+#include "webfuse/adapter/credentials.h"
 
 namespace
 {
@@ -43,10 +43,10 @@ void callback(
             break;
         case WF_CLIENT_AUTHENTICATE_GET_CREDENTIALS:
             {
-                auto * credentials = reinterpret_cast<wf_client_credentials*>(args);
-                wf_client_credentials_set_type(credentials, "username");
-                wf_client_credentials_add(credentials, "user", "bob");
-                wf_client_credentials_add(credentials, "password", "secret");
+                auto * credentials = reinterpret_cast<wf_credentials*>(args);
+                wf_credentials_set_type(credentials, "username");
+                wf_credentials_add(credentials, "user", "bob");
+                wf_credentials_add(credentials, "password", "secret");
             }
             break;
         case WF_CLIENT_FILESYSTEM_ADDED:
diff --git a/test/webfuse/tests/adapter/test_credentials.cc b/test/webfuse/tests/adapter/test_credentials.cc
index 88e2552..2e11a79 100644
--- a/test/webfuse/tests/adapter/test_credentials.cc
+++ b/test/webfuse/tests/adapter/test_credentials.cc
@@ -83,3 +83,31 @@ TEST(Credentials, FailedToGetWrongElementDataType)
     wf_impl_credentials_cleanup(&creds);
     json_decref(data);    
 }
+
+TEST(Credentials, SetType)
+{
+    struct wf_credentials creds;
+    wf_impl_credentials_init_default(&creds);
+
+    wf_credentials_set_type(&creds, "username");
+    ASSERT_STREQ("username", wf_credentials_type(&creds));
+
+    wf_impl_credentials_cleanup(&creds);
+}
+
+TEST(Credentials, Add)
+{
+    struct wf_credentials creds;
+    wf_impl_credentials_init_default(&creds);
+
+    wf_credentials_add(&creds, "a.value", "a");
+    ASSERT_STREQ("a", wf_credentials_get(&creds, "a.value"));
+
+    wf_credentials_add(&creds, "b.value", "b");
+    ASSERT_STREQ("b", wf_credentials_get(&creds, "b.value"));
+
+    wf_credentials_add(&creds, "a.value", "A");
+    ASSERT_STREQ("A", wf_credentials_get(&creds, "a.value"));
+
+    wf_impl_credentials_cleanup(&creds);
+}