diff --git a/source/core/Nes_Apu.h b/source/core/Nes_Apu.h
index 6a7ea67..60c1983 100644
--- a/source/core/Nes_Apu.h
+++ b/source/core/Nes_Apu.h
@@ -32,12 +32,12 @@ public:
 	// count, call end_frame( last_cpu_time ).
 	
 	// Write to register (0x4000-0x4017, except 0x4014 and 0x4016)
-	enum { start_addr = 0x4000 };
-	enum { end_addr   = 0x4017 };
+	static const uint16_t start_addr = 0x4000;
+	static const uint16_t end_addr   = 0x4017;
 	void write_register( nes_time_t, nes_addr_t, int data );
 	
 	// Read from status register at 0x4015
-	enum { status_addr = 0x4015 };
+	static const uint16_t status_addr = 0x4015;
 	int read_status( nes_time_t );
 	
 	// Run all oscillators up to specified time, end current time frame, then
@@ -67,7 +67,7 @@ public:
 	// the specified oscillator is muted and emulation accuracy is reduced.
 	// The oscillators are indexed as follows: 0) Square 1, 1) Square 2,
 	// 2) Triangle, 3) Noise, 4) DMC.
-	enum { osc_count = 5 };
+	static const uint16_t osc_count = 5;
 	void osc_output( int index, Blip_Buffer* buffer );
 	
 	// Set IRQ time callback that is invoked when the time of earliest IRQ
@@ -78,8 +78,8 @@ public:
 	// Get time that APU-generated IRQ will occur if no further register reads
 	// or writes occur. If IRQ is already pending, returns irq_waiting. If no
 	// IRQ will occur, returns no_irq.
-	enum { no_irq = LONG_MAX / 2 + 1 };
-	enum { irq_waiting = 0 };
+	static const uint64_t no_irq = LONG_MAX / 2 + 1;
+	static const uint16_t irq_waiting = 0;
 	nes_time_t earliest_irq( nes_time_t ) const;
 	
 	// Count number of DMC reads that would occur if 'run_until( t )' were executed.
diff --git a/source/core/Nes_Emu.h b/source/core/Nes_Emu.h
index 5e7888e..f4fb5d1 100644
--- a/source/core/Nes_Emu.h
+++ b/source/core/Nes_Emu.h
@@ -28,17 +28,17 @@ public:
 	// Size and depth of graphics buffer required for rendering. Note that this
 	// is larger than the actual image, with a temporary area around the edge
 	// that gets filled with junk.
-	enum { buffer_width  = Nes_Ppu::buffer_width };
-	int buffer_height() const { return buffer_height_; }
-	enum { bits_per_pixel = 8 };
+	static const uint16_t buffer_width  = Nes_Ppu::buffer_width;
+	uint16_t buffer_height() const { return buffer_height_; }
+	static const uint8_t bits_per_pixel = 8;
 
 	// Set graphics buffer to render pixels to. Pixels points to top-left pixel and
 	// row_bytes is the number of bytes to get to the next line (positive or negative).
 	void set_pixels( void* pixels, long row_bytes );
 
 	// Size of image generated in graphics buffer
-	enum { image_width   = 256 };
-	enum { image_height  = 240 };
+	static const uint16_t image_width   = 256;
+	static const uint16_t image_height  = 240;
 
     const uint8_t* getHostPixels () const { return emu.ppu.host_pixels; }
     
@@ -56,11 +56,13 @@ public:
 	virtual const char * emulate_skip_frame( int joypad1, int joypad2 = 0 );
 
 	// Maximum size of palette that can be generated
-	enum { max_palette_size = 256 };
+	static const uint16_t max_palette_size = 256;
 
 	// Result of current frame
 	struct frame_t
 	{
+		static const uint8_t left = 8;
+		
 		int joypad_read_count;  // number of times joypads were strobed (read)
 		int burst_phase;        // NTSC burst phase for frame (0, 1, or 2)
 
@@ -68,7 +70,6 @@ public:
 		int chan_count;         // 1: mono, 2: stereo
 
 		int top;                // top-left position of image in graphics buffer
-		enum { left = 8 };
 		unsigned char* pixels;  // pointer to top-left pixel of image
 		long pitch;             // number of bytes to get to next row of image
 
diff --git a/source/core/Nes_Ppu_Impl.h b/source/core/Nes_Ppu_Impl.h
index 1a27218..c336316 100644
--- a/source/core/Nes_Ppu_Impl.h
+++ b/source/core/Nes_Ppu_Impl.h
@@ -23,33 +23,34 @@ public:
 	void save_state( Nes_State_* out ) const;
 	void load_state( Nes_State_ const& );
 	
-	enum { image_width = 256 };
-	enum { image_height = 240 };
-	enum { image_left = 8 };
-	enum { buffer_width = image_width + 16 };
-	enum { buffer_height = image_height };
+	static const uint16_t image_width = 256;
+	static const uint16_t image_height = 240;
+	static const uint16_t image_left = 8;
+	static const uint16_t buffer_width = image_width + 16;
+	static const uint16_t buffer_height = image_height;
 	
 	int write_2007( int );
 	
 	// Host palette
-	enum { palette_increment = 64 };
+	static const uint8_t palette_increment = 64;
 	short* host_palette;
 	int palette_begin;
 	int max_palette_size;
 	int palette_size; // set after frame is rendered
 	
 	// Mapping
-	enum { vaddr_clock_mask = 0x1000 };
+	static const uint16_t vaddr_clock_mask = 0x1000;
 	void set_nt_banks( int bank0, int bank1, int bank2, int bank3 );
 	void set_chr_bank( int addr, int size, long data );
 	void set_chr_bank_ex( int addr, int size, long data );
 	
 	// Nametable and CHR RAM
-	enum { nt_ram_size = 0x1000 };
-	enum { chr_addr_size = 0x2000 };
-	enum { bytes_per_tile = 16 };
-	enum { chr_tile_count = chr_addr_size / bytes_per_tile };
-	enum { mini_offscreen_height = 16 }; // double-height sprite
+	static const uint16_t nt_ram_size = 0x1000;
+	static const uint16_t chr_addr_size = 0x2000;
+	static const uint8_t bytes_per_tile = 16;
+	static const uint16_t chr_tile_count = chr_addr_size / bytes_per_tile;
+	static const uint8_t mini_offscreen_height = 16; // double-height sprite
+
 	struct impl_t
 	{
 		uint8_t nt_ram [nt_ram_size];
@@ -60,7 +61,8 @@ public:
 		};
 	};
 	impl_t* impl;
-	enum { scanline_len = 341 };
+
+	static const uint16_t scanline_len = 341;
 	
 protected:
 	uint8_t spr_ram [0x100];
@@ -73,7 +75,7 @@ protected: //friend class Nes_Ppu; private:
 	int addr_inc; // pre-calculated $2007 increment (based on w2001 & 0x04)
 	int read_2007( int addr );
 	
-	enum { last_sprite_max_scanline = 240 };
+	static const uint16_t last_sprite_max_scanline = 240;
 	long recalc_sprite_max( int scanline );
 	int first_opaque_sprite_line();
 	
@@ -99,7 +101,7 @@ private:
 	int sprite_tile_index( uint8_t const* sprite ) const;
 	
 	// Mapping
-	enum { chr_page_size = 0x400 };
+	static const uint16_t chr_page_size = 0x400;
 	long chr_pages [chr_addr_size / chr_page_size];
 	long chr_pages_ex [chr_addr_size / chr_page_size];
 	long map_chr_addr( unsigned a ) /*const*/
diff --git a/source/core/abstract_file.h b/source/core/abstract_file.h
index 663d829..99af53a 100644
--- a/source/core/abstract_file.h
+++ b/source/core/abstract_file.h
@@ -26,8 +26,8 @@ private:
 // Write data to memory
 class Mem_Writer : public Data_Writer {
 	char* data_;
-	long size_;
-	long allocated;
+	size_t size_;
+	size_t allocated;
 	enum { expanding, fixed, ignore_excess } mode;
 public:
 	// Keep all written data in expanding block of memory
@@ -43,7 +43,7 @@ public:
 	char* data() { return data_; }
 	
 	// Number of bytes written
-	long size() const { return size_; }
+	size_t size() const { return size_; }
 	
 	~Mem_Writer();
 };
diff --git a/source/player.cpp b/source/player.cpp
index 7cdad23..20493bd 100644
--- a/source/player.cpp
+++ b/source/player.cpp
@@ -73,8 +73,6 @@ int main(int argc, char *argv[])
   // Creating emulator instance
   auto e = EmuInstance(romFilePath, stateFilePath);
 
-  auto stateHash = e.getStateHash();
-
   // Creating playback instance
   auto p = PlaybackInstance(&e, sequence);