diff --git a/kotlin-native/platformLibs/src/platform/mingw/winhttp.def b/kotlin-native/platformLibs/src/platform/mingw/winhttp.def
new file mode 100644
index 00000000000..49dd0adb5e5
--- /dev/null
+++ b/kotlin-native/platformLibs/src/platform/mingw/winhttp.def
@@ -0,0 +1,135 @@
+package = platform.winhttp
+headers = wtypes.h winhttp.h
+headerFilter = winhttp.h
+
+compilerOpts = -DUNICODE
+linkerOpts = -lwinhttp
+depends = posix windows
+---
+// Note that some of definitions can overlap with definitions from platform.windows
+// Some of them have the same value (e.g. SECURITY_FLAG_IGNORE_UNKNOWN_CA),
+// Others do not (INTERNET_SCHEME_HTTP).
+// To make things simple and correct, we don't try to undefine them.
+// In case of collision, users can import declaration explicitly
+// For example, `import platform.windows.INTERNET_SCHEME_HTTP`.
+
+// These WebSocket declarations are not present in our sysroots,
+// so we add them here.
+#define WINHTTP_OPTION_UPGRADE_TO_WEB_SOCKET            114
+
+typedef enum _WINHTTP_WEB_SOCKET_OPERATION
+{
+    WINHTTP_WEB_SOCKET_SEND_OPERATION                   = 0,
+    WINHTTP_WEB_SOCKET_RECEIVE_OPERATION                = 1,
+    WINHTTP_WEB_SOCKET_CLOSE_OPERATION                  = 2,
+    WINHTTP_WEB_SOCKET_SHUTDOWN_OPERATION               = 3
+} WINHTTP_WEB_SOCKET_OPERATION;
+
+typedef enum _WINHTTP_WEB_SOCKET_BUFFER_TYPE
+{
+    WINHTTP_WEB_SOCKET_BINARY_MESSAGE_BUFFER_TYPE       = 0,
+    WINHTTP_WEB_SOCKET_BINARY_FRAGMENT_BUFFER_TYPE      = 1,
+    WINHTTP_WEB_SOCKET_UTF8_MESSAGE_BUFFER_TYPE         = 2,
+    WINHTTP_WEB_SOCKET_UTF8_FRAGMENT_BUFFER_TYPE        = 3,
+    WINHTTP_WEB_SOCKET_CLOSE_BUFFER_TYPE                = 4
+} WINHTTP_WEB_SOCKET_BUFFER_TYPE;
+
+typedef enum _WINHTTP_WEB_SOCKET_CLOSE_STATUS
+{
+    WINHTTP_WEB_SOCKET_SUCCESS_CLOSE_STATUS                = 1000,
+    WINHTTP_WEB_SOCKET_ENDPOINT_TERMINATED_CLOSE_STATUS    = 1001,
+    WINHTTP_WEB_SOCKET_PROTOCOL_ERROR_CLOSE_STATUS         = 1002,
+    WINHTTP_WEB_SOCKET_INVALID_DATA_TYPE_CLOSE_STATUS      = 1003,
+    WINHTTP_WEB_SOCKET_EMPTY_CLOSE_STATUS                  = 1005,
+    WINHTTP_WEB_SOCKET_ABORTED_CLOSE_STATUS                = 1006,
+    WINHTTP_WEB_SOCKET_INVALID_PAYLOAD_CLOSE_STATUS        = 1007,
+    WINHTTP_WEB_SOCKET_POLICY_VIOLATION_CLOSE_STATUS       = 1008,
+    WINHTTP_WEB_SOCKET_MESSAGE_TOO_BIG_CLOSE_STATUS        = 1009,
+    WINHTTP_WEB_SOCKET_UNSUPPORTED_EXTENSIONS_CLOSE_STATUS = 1010,
+    WINHTTP_WEB_SOCKET_SERVER_ERROR_CLOSE_STATUS           = 1011,
+    WINHTTP_WEB_SOCKET_SECURE_HANDSHAKE_ERROR_CLOSE_STATUS = 1015
+} WINHTTP_WEB_SOCKET_CLOSE_STATUS;
+
+typedef struct _WINHTTP_WEB_SOCKET_ASYNC_RESULT
+{
+    WINHTTP_ASYNC_RESULT AsyncResult;
+    WINHTTP_WEB_SOCKET_OPERATION Operation;
+} WINHTTP_WEB_SOCKET_ASYNC_RESULT;
+
+typedef struct _WINHTTP_WEB_SOCKET_STATUS
+{
+    DWORD dwBytesTransferred;
+    WINHTTP_WEB_SOCKET_BUFFER_TYPE eBufferType;
+} WINHTTP_WEB_SOCKET_STATUS;
+
+#define WINHTTP_WEB_SOCKET_MAX_CLOSE_REASON_LENGTH 123
+#define WINHTTP_WEB_SOCKET_MIN_KEEPALIVE_VALUE 15000
+
+#define WINHTTP_CALLBACK_STATUS_CLOSE_COMPLETE          0x02000000
+#define WINHTTP_CALLBACK_STATUS_SHUTDOWN_COMPLETE       0x04000000
+
+WINHTTPAPI
+HINTERNET
+WINAPI
+WinHttpWebSocketCompleteUpgrade
+(
+    _In_ HINTERNET hRequest,
+    _In_opt_ DWORD_PTR pContext
+);
+
+WINHTTPAPI
+DWORD
+WINAPI
+WinHttpWebSocketSend
+(
+    _In_ HINTERNET hWebSocket,
+    _In_ WINHTTP_WEB_SOCKET_BUFFER_TYPE eBufferType,
+    _In_reads_opt_(dwBufferLength) PVOID pvBuffer,
+    _In_ DWORD dwBufferLength
+);
+
+WINHTTPAPI
+DWORD
+WINAPI
+WinHttpWebSocketReceive
+(
+    _In_ HINTERNET hWebSocket,
+    _Out_writes_bytes_to_(dwBufferLength, *pdwBytesRead) PVOID pvBuffer,
+    _In_ DWORD dwBufferLength,
+    _Out_range_(0, dwBufferLength) DWORD *pdwBytesRead,
+    _Out_ WINHTTP_WEB_SOCKET_BUFFER_TYPE *peBufferType
+);
+
+WINHTTPAPI
+DWORD
+WINAPI
+WinHttpWebSocketShutdown
+(
+    _In_ HINTERNET hWebSocket,
+    _In_ USHORT usStatus,
+    _In_reads_bytes_opt_(dwReasonLength) PVOID pvReason,
+    _In_range_(0, WINHTTP_WEB_SOCKET_MAX_CLOSE_REASON_LENGTH) DWORD dwReasonLength
+);
+
+WINHTTPAPI
+DWORD
+WINAPI
+WinHttpWebSocketClose
+(
+    _In_ HINTERNET hWebSocket,
+    _In_ USHORT usStatus,
+    _In_reads_bytes_opt_(dwReasonLength) PVOID pvReason,
+    _In_range_(0, WINHTTP_WEB_SOCKET_MAX_CLOSE_REASON_LENGTH) DWORD dwReasonLength
+);
+
+WINHTTPAPI
+DWORD
+WINAPI
+WinHttpWebSocketQueryCloseStatus
+(
+    _In_ HINTERNET hWebSocket,
+    _Out_ USHORT *pusStatus,
+    _Out_writes_bytes_to_opt_(dwReasonLength, *pdwReasonLengthConsumed) PVOID pvReason,
+    _In_range_(0, WINHTTP_WEB_SOCKET_MAX_CLOSE_REASON_LENGTH) DWORD dwReasonLength,
+    _Out_range_(0, WINHTTP_WEB_SOCKET_MAX_CLOSE_REASON_LENGTH) DWORD *pdwReasonLengthConsumed
+);
\ No newline at end of file