diff --git a/firmware/lib/basic/AllocAbstraction.h b/firmware/lib/basic/AllocAbstraction.h
new file mode 100644
index 0000000..3f1fbcb
--- /dev/null
+++ b/firmware/lib/basic/AllocAbstraction.h
@@ -0,0 +1,13 @@
+#pragma once
+
+#ifdef PLATFORM_NATIVE
+
+#include <stdlib.h>
+
+static constexpr uint32_t MALLOC_CAP_SPIRAM = -1;
+
+inline void *heap_caps_malloc(size_t size, uint32_t /*caps*/) {
+  return std::malloc(size);
+}
+
+#endif
\ No newline at end of file
diff --git a/firmware/lib/basic/FilesystemAbstraction.h b/firmware/lib/basic/FilesystemAbstraction.h
index 6fc20b8..f9ac66b 100644
--- a/firmware/lib/basic/FilesystemAbstraction.h
+++ b/firmware/lib/basic/FilesystemAbstraction.h
@@ -8,6 +8,12 @@
 namespace portablefs
 {
     using File = ::File;
+    using string = String;
+
+    template<typename T> 
+    String to_string(const T & value) {
+        return String(value);
+    }
 
     class Dir
     {
@@ -85,20 +91,11 @@ namespace portablefs
         return SPIFFS.totalBytes();
     }
 
+
 } // namespace portablefs
 
 #endif
 
-#ifdef PLATFORM_ESP8266
-
-#include <FS.h>
-
-namespace portablefs
-{
-    using Dir;
-} // namespace portablefs
-
-#endif
 
 #ifdef PLATFORM_NATIVE
 
@@ -108,18 +105,27 @@ namespace portablefs
 
 namespace fs = std::filesystem;
 
+enum SeekMode {
+    SeekSet = 0,
+    SeekCur = 1,
+    SeekEnd = 2
+};
+
 
 namespace portablefs
 {
     const std::string basePath = "./base";
+    using string = std::string;
     
+    using std::to_string;
+
     class Dir
     {
     public:
         Dir() {}
         Dir(const String &path)
-            : it_(fs::directory_iterator(path).begin()),
-              end_(fs::directory_iterator(path).end()),
+            : it_(fs::directory_iterator(path)),
+              end_(fs::directory_iterator()),
               firstIncremented_(false)
         {
         }
@@ -136,22 +142,22 @@ namespace portablefs
 
         bool isFile()
         {
-            return file.is_regular_file();
+            return it_->is_regular_file();
         }
 
         bool isDirectory()
         {
-            return it_.is_directory();
+            return it_->is_directory();
         }
 
         String fileName() const
         {
-            return it_.path().filename().string();
+            return it_->path().filename().string();
         }
 
         size_t fileSize() const
         {
-            return it_.file_size();
+            return it_->file_size();
         }
 
     private:
@@ -165,28 +171,73 @@ namespace portablefs
         return Dir(path);
     }
 
+    class File 
+    {
+    public:
+        File(std::FILE * file) : file_(file) {}
+
+        bool seek(uint32_t pos, SeekMode mode) 
+        {
+            if(mode == SeekSet)
+                return std::fseek(file_, pos, SEEK_SET) == 0;
+            else if (mode == SeekCur)
+                return std::fseek(file_, pos, SEEK_CUR) == 0;
+            else 
+                return std::fseek(file_, pos, SEEK_END) == 0;
+        }
+
+        bool seek(uint32_t pos) { return std::fseek(file_, pos, SEEK_SET); }
+
+        size_t write(const uint8_t *buf, size_t size) {
+            return std::fwrite(buf, size, 1UL, file_);
+        }
+
+        size_t size() {
+            auto current_position = ftell(file_);
+            seek(0, SeekEnd);
+            auto end = ftell(file_);
+            seek(0, SeekSet);
+            auto begin = ftell(file_);
+            seek(current_position, SeekSet);
+            return end - begin;
+        }
+
+    private:
+        std::FILE * file_;
+    };
+
     inline File open(const char *name, const char *mode)
     {
-        if(mode == "r")
-            return fopen()
-        return SPIFFS.open(name, mode);
+        std::string modeStr;
+        if(modeStr.find("b") == std::string::npos)
+            modeStr += "b";
+        return File(std::fopen(name, modeStr.c_str()));
     }
 
     inline bool exists(const char *name)
     {
-        return SPIFFS.exists(name);
+        return fs::exists(fs::path(name));
     }
 
     inline bool remove(const char *name)
     {
-        return SPIFFS.remove(name);
+        return fs::remove(fs::path(name));
     }
 
     inline bool mkdir(const char *name)
     {
-        return SPIFFS.mkdir(name);
+        return fs::create_directory(fs::path(name));
     }    
 
+    //inline size_t totalBytes() {
+    //    return 1024 * 1024 * 4; // some dummy value
+    //}
+    //inline size_t usedBytes() {
+    //    // TODO: makes more sense to report total file size of all files in folder
+    //    return 1024; // some dummy value 
+    //}
+
+
 } // namespace portablefs
 
 #endif
\ No newline at end of file
diff --git a/firmware/lib/basic/MockSerial.h b/firmware/lib/basic/MockSerial.h
index 6daaccb..26fb51d 100644
--- a/firmware/lib/basic/MockSerial.h
+++ b/firmware/lib/basic/MockSerial.h
@@ -2,6 +2,7 @@
 
 #include <iostream>
 
+#ifdef PLATFORM_NATIVE
 
 class SerialMock {
 public:
@@ -15,4 +16,7 @@ public:
     }
 };
 
-static SerialMock Serial;
\ No newline at end of file
+static SerialMock Serial;
+
+
+#endif
\ No newline at end of file
diff --git a/firmware/lib/basic/PreferencesAbstraction.h b/firmware/lib/basic/PreferencesAbstraction.h
new file mode 100644
index 0000000..16f4337
--- /dev/null
+++ b/firmware/lib/basic/PreferencesAbstraction.h
@@ -0,0 +1,36 @@
+#pragma once
+
+
+#ifdef PLATFORM_ESP32
+#include "Preferences.h"
+#endif 
+
+
+
+#ifdef PLATFORM_NATIVE
+
+#include <map>
+
+class Preferences
+{
+  public:
+    std::string getString(const char * key, const std::string & defaultValue) const {
+      std::string strKey(key);
+      const auto it = strings_.find(strKey);
+      return (it == string_.end()) ? defaultValue : *it;
+    }
+
+    size_t putString(const char * key, const char * value) {
+      strings_[std::string(key)] = std::string(value);
+      return std::strlen(value);
+    }
+
+    bool remove(const char * key) {
+      return strings_.remove(key); 
+    }
+
+  private:
+    std::map<std::string, std::string> strings_;
+};
+
+#endif // PLATFORM_NATIVE
diff --git a/firmware/lib/basic/TimeAbstraction.h b/firmware/lib/basic/TimeAbstraction.h
new file mode 100644
index 0000000..b3015f9
--- /dev/null
+++ b/firmware/lib/basic/TimeAbstraction.h
@@ -0,0 +1,16 @@
+#pragma once
+
+#ifdef PLATFORM_ESP32
+#include <Arduino.h>
+#endif 
+
+#ifdef PLATFORM_NATIVE
+
+#include <chrono>
+
+inline unsigned long millis() {
+  static auto timeOfFirstCall = std::chrono::steady_clock::now();
+  const auto timePoint = std::chrono::steady_clock::now();
+  return std::chrono::duration_cast<std::chrono::milliseconds>(timePoint - timeOfFirstCall).count();
+}
+#endif
\ No newline at end of file
diff --git a/firmware/lib/logging/Logger.cpp b/firmware/lib/logging/Logger.cpp
index 7c72de7..a8f8be3 100644
--- a/firmware/lib/logging/Logger.cpp
+++ b/firmware/lib/logging/Logger.cpp
@@ -1,4 +1,5 @@
 #include "Logger.h"
+#include "AllocAbstraction.h"
 
 constexpr size_t LOG_SIZE = 1024 * 1024 * 2;
 
@@ -12,10 +13,12 @@ Logger *Logger::getInstance()
 void Logger::init()
 {
   theLogger = new Logger();
+  #ifdef PLATFORM_ESP32
   Serial.begin(115200);
   while (!Serial)
   {
   }
+  #endif
 }
 
 Logger::Logger()
diff --git a/firmware/lib/logging/Logger.h b/firmware/lib/logging/Logger.h
index 2666f81..b17a8ad 100644
--- a/firmware/lib/logging/Logger.h
+++ b/firmware/lib/logging/Logger.h
@@ -1,6 +1,16 @@
 #pragma once
 
+#include "TimeAbstraction.h"
+
+#ifdef PLATFORM_ESP32
 #include "Arduino.h"
+#endif
+
+#ifdef PLATFORM_NATIVE
+#include <stdint.h>
+#include <string.h>
+#include <utility>
+#endif
 
 #define LOG_INFO(...)                        \
   {                                          \
diff --git a/firmware/lib/session/MockStorage.h b/firmware/lib/session/MockStorage.h
index 9b59164..b926a17 100644
--- a/firmware/lib/session/MockStorage.h
+++ b/firmware/lib/session/MockStorage.h
@@ -12,7 +12,7 @@ class VectorAdaptor {
 public:
     VectorAdaptor(std::vector<uint8_t> * v) : v_(v) {}
 
-    void write(const char *data, uint32_t size) {
+    void write(const uint8_t *data, uint32_t size) {
         v_->insert(v_->end(), data, data + size );
     }
 
@@ -38,7 +38,7 @@ public:
     FilePtrAdaptor(const FilePtrAdaptor &) = delete;
     void operator=(const FilePtrAdaptor &) = delete;
 
-    void write(const char *data, uint32_t size) {
+    void write(const uint8_t *data, uint32_t size) {
         fwrite(data, size, 1, fptr);
     }
 
diff --git a/firmware/lib/session/SimpleMeasurementSession.h b/firmware/lib/session/SimpleMeasurementSession.h
index 2d1984d..38d684f 100644
--- a/firmware/lib/session/SimpleMeasurementSession.h
+++ b/firmware/lib/session/SimpleMeasurementSession.h
@@ -1,7 +1,9 @@
 #include "Dtypes.h"
 #include "SessionChunk.h"
 #include "FilesystemAbstraction.h"
+#include "AllocAbstraction.h"
 #include "Logger.h"
+#include "SwimTrackerConfig.h"
 
 
 template <typename Measurement_T, uint32_t MAX_SIZE>
@@ -85,7 +87,8 @@ private:
         deleteUntilBytesFree(CONFIG_SESSION_MAX_SIZE);
         LOG_INFO("   %ld after deleteUntilBytesFree()", millis());
 
-        String filename = String(CONFIG_DATA_PATH) + "/" + String(chunk->getStartTime());
+        using fs_string = portablefs::string;
+        fs_string filename = fs_string(CONFIG_DATA_PATH) + "/" + portablefs::to_string(chunk->getStartTime());
         if (portablefs::exists(filename.c_str()))
         {
             auto file = portablefs::open(filename.c_str(), "r+");
@@ -111,6 +114,7 @@ private:
 
     void deleteUntilBytesFree(size_t requiredSpace)
     {
+        #ifdef PLATFORM_ESP32
         auto freeBytes = portablefs::totalBytes() - portablefs::usedBytes();
         while (freeBytes < requiredSpace)
         {
@@ -140,6 +144,7 @@ private:
             assert(newFreeBytes > freeBytes);
             freeBytes = newFreeBytes;
         }
+        #endif // PLATFORM_ESP32
     }
 
     ChunkT *chunk;
diff --git a/firmware/lib/session/StreamingMsgPackEncoder.h b/firmware/lib/session/StreamingMsgPackEncoder.h
index ba39e40..80f3928 100644
--- a/firmware/lib/session/StreamingMsgPackEncoder.h
+++ b/firmware/lib/session/StreamingMsgPackEncoder.h
@@ -1,4 +1,5 @@
 #pragma once
+#include "Logger.h"
 
 template<typename T> struct TypeToMsgPackCode{};
 template<> struct TypeToMsgPackCode<uint8_t> { static const char CODE; };
@@ -52,7 +53,7 @@ public:
         else
         {
             size |= 0b10000000;
-            writer->write((byte*)(&size), 1);
+            writer->write((uint8_t*)(&size), 1);
         }
     }
 
diff --git a/firmware/lib/wifimanager/WifiManager.h b/firmware/lib/wifimanager/WifiManager.h
index 5494692..5804608 100644
--- a/firmware/lib/wifimanager/WifiManager.h
+++ b/firmware/lib/wifimanager/WifiManager.h
@@ -1,6 +1,6 @@
 #pragma once
 
-#include "Preferences.h"
+#include "PreferencesAbstraction.h"
 #include <WiFi.h>
 
 /**
diff --git a/firmware/src/native_main.cpp b/firmware/src/native_main.cpp
new file mode 100644
index 0000000..00fd3c1
--- /dev/null
+++ b/firmware/src/native_main.cpp
@@ -0,0 +1,5 @@
+#include "Logger.h"
+
+
+int main()
+{}
\ No newline at end of file