diff --git a/include/nn/account.h b/include/nn/account.h
index 18ee1f2e..a546c818 100644
--- a/include/nn/account.h
+++ b/include/nn/account.h
@@ -10,8 +10,12 @@
 
 namespace nn {
 namespace account {
-typedef char Nickname[0x21];
-typedef u64 NetworkServiceAccountId;
+struct Nickname {
+    char m_Buffer[0x21];
+};
+struct NetworkServiceAccountId {
+    u64 m_Id;
+};
 
 class AsyncContext;
 
@@ -40,6 +44,7 @@ Result LoadNetworkServiceAccountIdTokenCache(u64*, char*, u64, UserHandle const&
 
 Result GetLastOpenedUser(Uid*);
 Result GetNickname(Nickname* nickname, Uid const& userID);
+Result GetNetworkServiceAccountId(NetworkServiceAccountId*, const UserHandle&);
 
 Result GetUserId(Uid* uid, const UserHandle& handle);
 Result OpenPreselectedUser(UserHandle* handle);
@@ -47,6 +52,7 @@ Result OpenPreselectedUser(UserHandle* handle);
 class AsyncContext {
 public:
     AsyncContext();
+    ~AsyncContext();
 
     Result HasDone(bool*);
     Result GetResult();
diff --git a/include/nn/audio.h b/include/nn/audio.h
index bd8c86e9..ab140895 100644
--- a/include/nn/audio.h
+++ b/include/nn/audio.h
@@ -147,6 +147,7 @@ struct VoiceType {
 };
 
 struct DeviceSinkType {
+    struct DownMixParameter;
     u64* _0;
 };
 
diff --git a/include/nn/friends.h b/include/nn/friends.h
index d5bd2506..4f554195 100644
--- a/include/nn/friends.h
+++ b/include/nn/friends.h
@@ -10,7 +10,12 @@
 
 namespace nn {
 namespace friends {
-typedef char Url[0xA0];
+struct Url {
+    char m_Buffer[0xA0];
+};
+struct ImageSize {
+    s32 m_Size;
+};
 
 class AsyncContext;
 class Profile;
@@ -27,7 +32,7 @@ class Profile {
     nn::account::NetworkServiceAccountId GetAccountId() const;
     nn::account::Nickname& GetNickname() const;
     bool IsValid() const;
-    Result GetProfileImageUrl(nn::friends::Url*, s32);
+    Result GetProfileImageUrl(nn::friends::Url*, ImageSize) const;
 };
 
 class AsyncContext {
diff --git a/include/nn/fs/fs_rom.h b/include/nn/fs/fs_rom.h
index da1dc8e1..6220ec91 100644
--- a/include/nn/fs/fs_rom.h
+++ b/include/nn/fs/fs_rom.h
@@ -1,6 +1,7 @@
 #pragma once
 
 #include <nn/fs/fs_types.h>
+#include <nn/nn.h>
 
 namespace nn::fs {
 
diff --git a/include/nn/fs/fs_save.h b/include/nn/fs/fs_save.h
index 03a9b154..6dda8d05 100644
--- a/include/nn/fs/fs_save.h
+++ b/include/nn/fs/fs_save.h
@@ -2,10 +2,7 @@
 
 #include <nn/account.h>
 #include <nn/fs/fs_types.h>
-
-namespace nn {
-typedef u64 ApplicationId;
-};
+#include <nn/nn.h>
 
 namespace nn::fs {
 
diff --git a/include/nn/fs/fs_types.h b/include/nn/fs/fs_types.h
index 132fdf7c..729c6442 100644
--- a/include/nn/fs/fs_types.h
+++ b/include/nn/fs/fs_types.h
@@ -2,10 +2,7 @@
 
 #include <nn/types.h>
 
-namespace nn {
-typedef u64 ApplicationId;
-
-namespace fs {
+namespace nn::fs {
 using namespace ams::fs;  // for errors
 
 typedef u64 UserId;
@@ -78,5 +75,4 @@ struct WriteOption {
         return op;
     }
 };
-}  // namespace fs
-}  // namespace nn
+}  // namespace nn::fs
diff --git a/include/nn/image.h b/include/nn/image.h
index f9712ba8..165a4cda 100644
--- a/include/nn/image.h
+++ b/include/nn/image.h
@@ -35,7 +35,7 @@ class JpegDecoder {
     nn::image::JpegStatus Analyze();
     nn::image::Dimension GetAnalyzedDimension() const;
     s64 GetAnalyzedWorkBufferSize() const;
-    JpegStatus Decode(void* out, s64, s32 alignment, void*, s64);
+    JpegStatus Decode(void* out, u64, s32 alignment, void*, u64);
 
     nn::image::ProcessStage mProcessStage;  // _8
     void* mData;                            // _C
diff --git a/include/nn/nfp/nfp.h b/include/nn/nfp/nfp.h
index e02f754c..ec041618 100644
--- a/include/nn/nfp/nfp.h
+++ b/include/nn/nfp/nfp.h
@@ -8,7 +8,9 @@ struct SystemEventType;
 
 namespace nn::nfp {
 
-using DeviceHandle = u64;
+struct DeviceHandle {
+    u64 m_Id;
+};
 
 enum State : u32;
 enum DeviceState : u32;
diff --git a/include/nn/nn.h b/include/nn/nn.h
index d367d9b8..286fe4f3 100644
--- a/include/nn/nn.h
+++ b/include/nn/nn.h
@@ -8,8 +8,10 @@
 #include <nn/types.h>
 
 namespace nn {
-typedef u64 ApplicationId;
+struct ApplicationId {
+    u64 m_Id;
 };
+}  // namespace nn
 
 #ifdef __cplusplus
 extern "C" {
@@ -30,4 +32,4 @@ void __nnDetailNintendoSdkNsoFile_0();
 
 #ifdef __cplusplus
 }
-#endif
\ No newline at end of file
+#endif