diff --git a/src/cavegen.cpp b/src/cavegen.cpp
index 1c25ce71..dc7355fe 100644
--- a/src/cavegen.cpp
+++ b/src/cavegen.cpp
@@ -35,7 +35,7 @@ static NoiseParams nparams_caveliquids(0, 1, v3f(150.0, 150.0, 150.0), 776, 3, 0
 
 CavesNoiseIntersection::CavesNoiseIntersection(
 	INodeDefManager *nodedef, BiomeManager *biomemgr, v3s16 chunksize,
-	NoiseParams *np_cave1, NoiseParams *np_cave2, int seed, float cave_width)
+	NoiseParams *np_cave1, NoiseParams *np_cave2, s32 seed, float cave_width)
 {
 	assert(nodedef);
 	assert(biomemgr);
@@ -130,7 +130,7 @@ void CavesNoiseIntersection::generateCaves(MMVManip *vm,
 CavesRandomWalk::CavesRandomWalk(
 	INodeDefManager *ndef,
 	GenerateNotifier *gennotify,
-	int seed,
+	s32 seed,
 	int water_level,
 	content_t water_source,
 	content_t lava_source)
diff --git a/src/cavegen.h b/src/cavegen.h
index da089463..2bf503d4 100644
--- a/src/cavegen.h
+++ b/src/cavegen.h
@@ -41,7 +41,7 @@ class CavesNoiseIntersection {
 public:
 	CavesNoiseIntersection(INodeDefManager *nodedef, BiomeManager *biomemgr,
 		v3s16 chunksize, NoiseParams *np_cave1, NoiseParams *np_cave2,
-		int seed, float cave_width);
+		s32 seed, float cave_width);
 	~CavesNoiseIntersection();
 
 	void generateCaves(MMVManip *vm, v3s16 nmin, v3s16 nmax, u8 *biomemap);
@@ -83,7 +83,7 @@ public:
 	s16 *heightmap;
 
 	// configurable parameters
-	int seed;
+	s32 seed;
 	int water_level;
 	int lava_depth;
 	NoiseParams *np_caveliquids;
@@ -122,7 +122,7 @@ public:
 	// If gennotify is NULL, generation events are not logged.
 	CavesRandomWalk(INodeDefManager *ndef,
 		GenerateNotifier *gennotify = NULL,
-		int seed = 0,
+		s32 seed = 0,
 		int water_level = 1,
 		content_t water_source = CONTENT_IGNORE,
 		content_t lava_source = CONTENT_IGNORE);
diff --git a/src/dungeongen.h b/src/dungeongen.h
index f0a5e5ba..89862748 100644
--- a/src/dungeongen.h
+++ b/src/dungeongen.h
@@ -39,7 +39,7 @@ int dir_to_facedir(v3s16 d);
 
 
 struct DungeonParams {
-	int seed;
+	s32 seed;
 
 	content_t c_water;
 	content_t c_river_water;
diff --git a/src/mapgen.cpp b/src/mapgen.cpp
index 041356e3..32f7e29e 100644
--- a/src/mapgen.cpp
+++ b/src/mapgen.cpp
@@ -89,11 +89,25 @@ Mapgen::Mapgen(int mapgenid, MapgenParams *params, EmergeManager *emerge) :
 {
 	generating  = false;
 	id          = mapgenid;
-	seed        = (int)params->seed;
 	water_level = params->water_level;
 	flags       = params->flags;
 	csize       = v3s16(1, 1, 1) * (params->chunksize * MAP_BLOCKSIZE);
 
+	/*
+		We are losing half our entropy by doing this, but it is necessary to
+		preserve reverse compatibility.  If the top half of our current 64 bit
+		seeds ever starts getting used, existing worlds will break due to a
+		different hash outcome and no way to differentiate between versions.
+
+		A solution could be to add a new bit to designate that the top half of
+		the seed value should be used, essentially a 1-bit version code, but
+		this would require increasing the total size of a seed to 9 bytes (yuck)
+
+		It's probably okay if this never gets fixed.  4.2 billion possibilities
+		ought to be enough for anyone.
+	*/
+	seed = (s32)params->seed;
+
 	vm        = NULL;
 	ndef      = emerge->ndef;
 	biomegen  = NULL;
@@ -107,7 +121,7 @@ Mapgen::~Mapgen()
 }
 
 
-u32 Mapgen::getBlockSeed(v3s16 p, int seed)
+u32 Mapgen::getBlockSeed(v3s16 p, s32 seed)
 {
 	return (u32)seed   +
 		p.Z * 38134234 +
@@ -116,7 +130,7 @@ u32 Mapgen::getBlockSeed(v3s16 p, int seed)
 }
 
 
-u32 Mapgen::getBlockSeed2(v3s16 p, int seed)
+u32 Mapgen::getBlockSeed2(v3s16 p, s32 seed)
 {
 	u32 n = 1619 * p.X + 31337 * p.Y + 52591 * p.Z + 1013 * seed;
 	n = (n >> 13) ^ n;
diff --git a/src/mapgen.h b/src/mapgen.h
index 10595faf..0342fd46 100644
--- a/src/mapgen.h
+++ b/src/mapgen.h
@@ -150,7 +150,7 @@ struct MapgenParams {
 */
 class Mapgen {
 public:
-	int seed;
+	s32 seed;
 	int water_level;
 	u32 flags;
 	bool generating;
@@ -171,8 +171,8 @@ public:
 	Mapgen(int mapgenid, MapgenParams *params, EmergeManager *emerge);
 	virtual ~Mapgen();
 
-	static u32 getBlockSeed(v3s16 p, int seed);
-	static u32 getBlockSeed2(v3s16 p, int seed);
+	static u32 getBlockSeed(v3s16 p, s32 seed);
+	static u32 getBlockSeed2(v3s16 p, s32 seed);
 	s16 findGroundLevelFull(v2s16 p2d);
 	s16 findGroundLevel(v2s16 p2d, s16 ymin, s16 ymax);
 	s16 findLiquidSurface(v2s16 p2d, s16 ymin, s16 ymax);
diff --git a/src/mg_biome.h b/src/mg_biome.h
index e78e90e5..389b7664 100644
--- a/src/mg_biome.h
+++ b/src/mg_biome.h
@@ -80,7 +80,7 @@ struct BiomeParams {
 	virtual void writeParams(Settings *settings) const = 0;
 	virtual ~BiomeParams() {}
 
-	int seed;
+	s32 seed;
 };
 
 class BiomeGen {
diff --git a/src/noise.cpp b/src/noise.cpp
index 2ddc3926..c57c98cc 100644
--- a/src/noise.cpp
+++ b/src/noise.cpp
@@ -156,7 +156,7 @@ s32 PcgRandom::randNormalDist(s32 min, s32 max, int num_trials)
 
 ///////////////////////////////////////////////////////////////////////////////
 
-float noise2d(int x, int y, int seed)
+float noise2d(int x, int y, s32 seed)
 {
 	unsigned int n = (NOISE_MAGIC_X * x + NOISE_MAGIC_Y * y
 			+ NOISE_MAGIC_SEED * seed) & 0x7fffffff;
@@ -166,7 +166,7 @@ float noise2d(int x, int y, int seed)
 }
 
 
-float noise3d(int x, int y, int z, int seed)
+float noise3d(int x, int y, int z, s32 seed)
 {
 	unsigned int n = (NOISE_MAGIC_X * x + NOISE_MAGIC_Y * y + NOISE_MAGIC_Z * z
 			+ NOISE_MAGIC_SEED * seed) & 0x7fffffff;
@@ -235,7 +235,7 @@ float triLinearInterpolationNoEase(
 	return linearInterpolation(u, v, z);
 }
 
-float noise2d_gradient(float x, float y, int seed, bool eased)
+float noise2d_gradient(float x, float y, s32 seed, bool eased)
 {
 	// Calculate the integer coordinates
 	int x0 = myfloor(x);
@@ -256,7 +256,7 @@ float noise2d_gradient(float x, float y, int seed, bool eased)
 }
 
 
-float noise3d_gradient(float x, float y, float z, int seed, bool eased)
+float noise3d_gradient(float x, float y, float z, s32 seed, bool eased)
 {
 	// Calculate the integer coordinates
 	int x0 = myfloor(x);
@@ -290,7 +290,7 @@ float noise3d_gradient(float x, float y, float z, int seed, bool eased)
 }
 
 
-float noise2d_perlin(float x, float y, int seed,
+float noise2d_perlin(float x, float y, s32 seed,
 	int octaves, float persistence, bool eased)
 {
 	float a = 0;
@@ -306,7 +306,7 @@ float noise2d_perlin(float x, float y, int seed,
 }
 
 
-float noise2d_perlin_abs(float x, float y, int seed,
+float noise2d_perlin_abs(float x, float y, s32 seed,
 	int octaves, float persistence, bool eased)
 {
 	float a = 0;
@@ -321,7 +321,7 @@ float noise2d_perlin_abs(float x, float y, int seed,
 }
 
 
-float noise3d_perlin(float x, float y, float z, int seed,
+float noise3d_perlin(float x, float y, float z, s32 seed,
 	int octaves, float persistence, bool eased)
 {
 	float a = 0;
@@ -336,7 +336,7 @@ float noise3d_perlin(float x, float y, float z, int seed,
 }
 
 
-float noise3d_perlin_abs(float x, float y, float z, int seed,
+float noise3d_perlin_abs(float x, float y, float z, s32 seed,
 	int octaves, float persistence, bool eased)
 {
 	float a = 0;
@@ -363,7 +363,7 @@ float contour(float v)
 ///////////////////////// [ New noise ] ////////////////////////////
 
 
-float NoisePerlin2D(NoiseParams *np, float x, float y, int seed)
+float NoisePerlin2D(NoiseParams *np, float x, float y, s32 seed)
 {
 	float a = 0;
 	float f = 1.0;
@@ -389,7 +389,7 @@ float NoisePerlin2D(NoiseParams *np, float x, float y, int seed)
 }
 
 
-float NoisePerlin3D(NoiseParams *np, float x, float y, float z, int seed)
+float NoisePerlin3D(NoiseParams *np, float x, float y, float z, s32 seed)
 {
 	float a = 0;
 	float f = 1.0;
@@ -416,7 +416,7 @@ float NoisePerlin3D(NoiseParams *np, float x, float y, float z, int seed)
 }
 
 
-Noise::Noise(NoiseParams *np_, int seed, u32 sx, u32 sy, u32 sz)
+Noise::Noise(NoiseParams *np_, s32 seed, u32 sx, u32 sy, u32 sz)
 {
 	memcpy(&np, np_, sizeof(np));
 	this->seed = seed;
@@ -543,7 +543,7 @@ void Noise::resizeNoiseBuf(bool is3d)
 void Noise::gradientMap2D(
 		float x, float y,
 		float step_x, float step_y,
-		int seed)
+		s32 seed)
 {
 	float v00, v01, v10, v11, u, v, orig_u;
 	u32 index, i, j, noisex, noisey;
@@ -607,7 +607,7 @@ void Noise::gradientMap2D(
 void Noise::gradientMap3D(
 		float x, float y, float z,
 		float step_x, float step_y, float step_z,
-		int seed)
+		s32 seed)
 {
 	float v000, v010, v100, v110;
 	float v001, v011, v101, v111;
diff --git a/src/noise.h b/src/noise.h
index 0e4252dd..41b93ae0 100644
--- a/src/noise.h
+++ b/src/noise.h
@@ -148,7 +148,7 @@ struct NoiseParams {
 class Noise {
 public:
 	NoiseParams np;
-	int seed;
+	s32 seed;
 	u32 sx;
 	u32 sy;
 	u32 sz;
@@ -157,7 +157,7 @@ public:
 	float *persist_buf;
 	float *result;
 
-	Noise(NoiseParams *np, int seed, u32 sx, u32 sy, u32 sz=1);
+	Noise(NoiseParams *np, s32 seed, u32 sx, u32 sy, u32 sz=1);
 	~Noise();
 
 	void setSize(u32 sx, u32 sy, u32 sz=1);
@@ -167,11 +167,11 @@ public:
 	void gradientMap2D(
 		float x, float y,
 		float step_x, float step_y,
-		int seed);
+		s32 seed);
 	void gradientMap3D(
 		float x, float y, float z,
 		float step_x, float step_y, float step_z,
-		int seed);
+		s32 seed);
 
 	float *perlinMap2D(float x, float y, float *persistence_map=NULL);
 	float *perlinMap3D(float x, float y, float z, float *persistence_map=NULL);
@@ -202,11 +202,11 @@ private:
 
 };
 
-float NoisePerlin2D(NoiseParams *np, float x, float y, int seed);
-float NoisePerlin3D(NoiseParams *np, float x, float y, float z, int seed);
+float NoisePerlin2D(NoiseParams *np, float x, float y, s32 seed);
+float NoisePerlin3D(NoiseParams *np, float x, float y, float z, s32 seed);
 
 inline float NoisePerlin2D_PO(NoiseParams *np, float x, float xoff,
-	float y, float yoff, int seed)
+	float y, float yoff, s32 seed)
 {
 	return NoisePerlin2D(np,
 		x + xoff * np->spread.X,
@@ -215,7 +215,7 @@ inline float NoisePerlin2D_PO(NoiseParams *np, float x, float xoff,
 }
 
 inline float NoisePerlin3D_PO(NoiseParams *np, float x, float xoff,
-	float y, float yoff, float z, float zoff, int seed)
+	float y, float yoff, float z, float zoff, s32 seed)
 {
 	return NoisePerlin3D(np,
 		x + xoff * np->spread.X,
@@ -225,22 +225,22 @@ inline float NoisePerlin3D_PO(NoiseParams *np, float x, float xoff,
 }
 
 // Return value: -1 ... 1
-float noise2d(int x, int y, int seed);
-float noise3d(int x, int y, int z, int seed);
+float noise2d(int x, int y, s32 seed);
+float noise3d(int x, int y, int z, s32 seed);
 
-float noise2d_gradient(float x, float y, int seed, bool eased=true);
-float noise3d_gradient(float x, float y, float z, int seed, bool eased=false);
+float noise2d_gradient(float x, float y, s32 seed, bool eased=true);
+float noise3d_gradient(float x, float y, float z, s32 seed, bool eased=false);
 
-float noise2d_perlin(float x, float y, int seed,
+float noise2d_perlin(float x, float y, s32 seed,
 		int octaves, float persistence, bool eased=true);
 
-float noise2d_perlin_abs(float x, float y, int seed,
+float noise2d_perlin_abs(float x, float y, s32 seed,
 		int octaves, float persistence, bool eased=true);
 
-float noise3d_perlin(float x, float y, float z, int seed,
+float noise3d_perlin(float x, float y, float z, s32 seed,
 		int octaves, float persistence, bool eased=false);
 
-float noise3d_perlin_abs(float x, float y, float z, int seed,
+float noise3d_perlin_abs(float x, float y, float z, s32 seed,
 		int octaves, float persistence, bool eased=false);
 
 inline float easeCurve(float t)
diff --git a/src/script/lua_api/l_env.cpp b/src/script/lua_api/l_env.cpp
index 8284c3fc..ebdea09e 100644
--- a/src/script/lua_api/l_env.cpp
+++ b/src/script/lua_api/l_env.cpp
@@ -758,7 +758,7 @@ int ModApiEnvMod::l_get_perlin_map(lua_State *L)
 		return 0;
 	v3s16 size = read_v3s16(L, 2);
 
-	int seed = (int)(env->getServerMap().getSeed());
+	s32 seed = (s32)(env->getServerMap().getSeed());
 	LuaPerlinNoiseMap *n = new LuaPerlinNoiseMap(&np, seed, size);
 	*(void **)(lua_newuserdata(L, sizeof(void *))) = n;
 	luaL_getmetatable(L, "PerlinNoiseMap");
diff --git a/src/script/lua_api/l_noise.cpp b/src/script/lua_api/l_noise.cpp
index 04dc6048..e0039371 100644
--- a/src/script/lua_api/l_noise.cpp
+++ b/src/script/lua_api/l_noise.cpp
@@ -146,7 +146,7 @@ const luaL_reg LuaPerlinNoise::methods[] = {
   LuaPerlinNoiseMap
 */
 
-LuaPerlinNoiseMap::LuaPerlinNoiseMap(NoiseParams *params, int seed, v3s16 size)
+LuaPerlinNoiseMap::LuaPerlinNoiseMap(NoiseParams *params, s32 seed, v3s16 size)
 {
 	m_is3d = size.Z > 1;
 	np = *params;
diff --git a/src/script/lua_api/l_noise.h b/src/script/lua_api/l_noise.h
index 492eb755..40bfd131 100644
--- a/src/script/lua_api/l_noise.h
+++ b/src/script/lua_api/l_noise.h
@@ -79,7 +79,7 @@ class LuaPerlinNoiseMap : public ModApiBase {
 	static int l_getMapSlice(lua_State *L);
 
 public:
-	LuaPerlinNoiseMap(NoiseParams *np, int seed, v3s16 size);
+	LuaPerlinNoiseMap(NoiseParams *np, s32 seed, v3s16 size);
 
 	~LuaPerlinNoiseMap();
 
@@ -111,7 +111,7 @@ private:
 	static int l_next(lua_State *L);
 
 public:
-	LuaPseudoRandom(int seed) :
+	LuaPseudoRandom(s32 seed) :
 		m_pseudo(seed) {}
 
 	// LuaPseudoRandom(seed)
diff --git a/src/treegen.cpp b/src/treegen.cpp
index 208f3455..36d387c5 100644
--- a/src/treegen.cpp
+++ b/src/treegen.cpp
@@ -31,7 +31,7 @@ namespace treegen
 {
 
 void make_tree(MMVManip &vmanip, v3s16 p0,
-		bool is_apple_tree, INodeDefManager *ndef, int seed)
+		bool is_apple_tree, INodeDefManager *ndef, s32 seed)
 {
 	/*
 		NOTE: Tree-placing code is currently duplicated in the engine
@@ -149,7 +149,7 @@ treegen::error make_ltree(MMVManip &vmanip, v3s16 p0,
 		INodeDefManager *ndef, TreeDef tree_definition)
 {
 	MapNode dirtnode(ndef->getId("mapgen_dirt"));
-	int seed;
+	s32 seed;
 	if (tree_definition.explicit_seed)
 		seed = tree_definition.seed + 14002;
 	else
@@ -649,7 +649,7 @@ v3f transposeMatrix(irr::core::matrix4 M, v3f v)
 }
 
 
-void make_jungletree(MMVManip &vmanip, v3s16 p0, INodeDefManager *ndef, int seed)
+void make_jungletree(MMVManip &vmanip, v3s16 p0, INodeDefManager *ndef, s32 seed)
 {
 	/*
 		NOTE: Tree-placing code is currently duplicated in the engine
@@ -748,7 +748,7 @@ void make_jungletree(MMVManip &vmanip, v3s16 p0, INodeDefManager *ndef, int seed
 }
 
 
-void make_pine_tree(MMVManip &vmanip, v3s16 p0, INodeDefManager *ndef, int seed)
+void make_pine_tree(MMVManip &vmanip, v3s16 p0, INodeDefManager *ndef, s32 seed)
 {
 	/*
 		NOTE: Tree-placing code is currently duplicated in the engine
diff --git a/src/treegen.h b/src/treegen.h
index 4b0089d1..4e6f95e6 100644
--- a/src/treegen.h
+++ b/src/treegen.h
@@ -54,19 +54,19 @@ namespace treegen {
 		bool thin_branches;
 		MapNode fruitnode;
 		int fruit_chance;
-		int seed;
+		s32 seed;
 		bool explicit_seed;
 	};
 
 	// Add default tree
 	void make_tree(MMVManip &vmanip, v3s16 p0,
-		bool is_apple_tree, INodeDefManager *ndef, int seed);
+		bool is_apple_tree, INodeDefManager *ndef, s32 seed);
 	// Add jungle tree
 	void make_jungletree(MMVManip &vmanip, v3s16 p0,
-		INodeDefManager *ndef, int seed);
+		INodeDefManager *ndef, s32 seed);
 	// Add pine tree
 	void make_pine_tree(MMVManip &vmanip, v3s16 p0,
-		INodeDefManager *ndef, int seed);
+		INodeDefManager *ndef, s32 seed);
 
 	// Add L-Systems tree (used by engine)
 	treegen::error make_ltree(MMVManip &vmanip, v3s16 p0, INodeDefManager *ndef,