diff --git a/dub.selections.json b/dub.selections.json
deleted file mode 100644
index c2bab4e..0000000
--- a/dub.selections.json
+++ /dev/null
@@ -1,6 +0,0 @@
-{
-	"fileVersion": 1,
-	"versions": {
-		"libxdiff": {"version":"e2396bc172eba813cdcd1a96c494e35d687f576a","repository":"git+https://git.zhirov.kz/dlang/xdiff.git"}
-	}
-}
diff --git a/source/app.d b/source/app.d
index b1e9a4b..7b3a7ed 100644
--- a/source/app.d
+++ b/source/app.d
@@ -1,20 +1,322 @@
-import libxdiff;
+import std.stdio : writeln, stderr, File;
+import std.getopt;
+import std.file : read, exists;
+import std.exception : enforce, collectException;
+import core.stdc.stdlib : malloc, free, realloc;
+import core.stdc.string : memcpy;
+import core.sys.posix.unistd : posix_write = write;
 
-import std.conv : to;
-import std.stdio : writefln, writeln;
-import std.file : read;
+import xdiff;
 
-void main()
+// ------------------------------
+// RAII для mmfile_t
+// ------------------------------
+struct MmFile
 {
-	auto file1 = new MMFile(cast(const(ubyte)[]) read("/tmp/diff1.d"));
-	auto file2 = new MMFile(cast(const(ubyte)[]) read("/tmp/diff2.d"));
+	mmfile_t mf;
 
-	auto patch = file1.computePatch(file2);
+	// фабрика вместо конструктора по умолчанию
+	static MmFile create(long bsize = 8 * 1024, ulong flags = XDL_MMF_ATOMIC)
+	{
+		MmFile m;
+		enforce(xdl_init_mmfile(&m.mf, bsize, flags) == 0, "xdl_init_mmfile failed");
+		return m;
+	}
 
-	writeln(patch);
-
-	writefln(
-		"file1: %s\nfile2: %s",
-		file1.size, file2.size
-	);
+	void deinit()
+	{
+		xdl_free_mmfile(&mf);
+	}
+}
+
+// ------------------------------
+// Коллбэки вывода
+// ------------------------------
+extern (C) int mmfileOut(void* priv, mmbuffer_t* mb, int nbuf)
+{
+	auto mmfOut = cast(mmfile_t*) priv;
+	return xdl_writem_mmfile(mmfOut, mb, nbuf) < 0 ? -1 : 0;
+}
+
+extern (C) int fdOut(void* priv, mmbuffer_t* mb, int nbuf)
+{
+	const fd = cast(int) cast(size_t) priv; // 1=stdout, 2=stderr
+	foreach (i; 0 .. nbuf)
+	{
+		auto ptr = mb[i].ptr;
+		auto left = cast(size_t) mb[i].size;
+		while (left)
+		{
+			auto n = posix_write(fd, ptr, left);
+			if (n < 0)
+				return -1;
+			ptr += n;
+			left -= cast(size_t) n;
+		}
+	}
+	return 0;
+}
+
+// ------------------------------
+// Загрузка/выгрузка
+// ------------------------------
+void loadMmFile(ref MmFile m, string path)
+{
+	try
+	{
+		enforce(exists(path), "no such file: " ~ path);
+		auto data = cast(const(char)[]) read(path); // читает весь файл
+		auto dst = cast(char*) xdl_mmfile_writeallocate(&m.mf, data.length);
+		enforce(dst !is null, "xdl_mmfile_writeallocate failed (null)");
+		if (data.length)
+			memcpy(dst, data.ptr, data.length);
+	}
+	catch (Exception e)
+	{
+		// пробрасываем с контекстом пути
+		throw new Exception("loadMmFile(" ~ path ~ "): " ~ e.msg);
+	}
+}
+
+void dumpMmFile(const ref MmFile m, string path)
+{
+	File f = File(path, "wb");
+	scope (exit)
+		f.close();
+	long sz = 0;
+	auto blk = cast(char*) xdl_mmfile_first(cast(mmfile_t*)&m.mf, &sz);
+	while (blk !is null)
+	{
+		f.rawWrite(blk[0 .. cast(size_t) sz]);
+		blk = cast(char*) xdl_mmfile_next(cast(mmfile_t*)&m.mf, &sz);
+	}
+}
+
+// ------------------------------
+// Аллокатор
+// ------------------------------
+extern (C) void* wrap_malloc(void*, uint size)
+{
+	return malloc(size);
+}
+
+extern (C) void wrap_free(void*, void* ptr)
+{
+	free(ptr);
+}
+
+extern (C) void* wrap_realloc(void*, void* ptr, uint size)
+{
+	return realloc(ptr, size);
+}
+
+void installAllocator()
+{
+	memallocator_t malt;
+	malt.priv = null;
+	malt.malloc = &wrap_malloc;
+	malt.free = &wrap_free;
+	malt.realloc = &wrap_realloc;
+	enforce(xdl_set_allocator(&malt) == 0, "xdl_set_allocator failed");
+}
+
+// ------------------------------
+// Команды
+// ------------------------------
+int doDiff(ref MmFile a, ref MmFile b, long ctxlen)
+{
+	xpparam_t xpp;
+	xpp.flags = 0;
+	xdemitconf_t xecfg;
+	xecfg.ctxlen = ctxlen;
+	xdemitcb_t ecb;
+	ecb.priv = cast(void*) cast(size_t) 1;
+	ecb.outf = &fdOut;
+	return xdl_diff(&a.mf, &b.mf, &xpp, &xecfg, &ecb);
+}
+
+int doPatch(ref MmFile orig, ref MmFile patch, int mode)
+{
+	xdemitcb_t outcb;
+	outcb.priv = cast(void*) cast(size_t) 1;
+	outcb.outf = &fdOut;
+	xdemitcb_t rejcb;
+	rejcb.priv = cast(void*) cast(size_t) 2;
+	rejcb.outf = &fdOut;
+	return xdl_patch(&orig.mf, &patch.mf, mode, &outcb, &rejcb);
+}
+
+int doBDiff(ref MmFile a, ref MmFile b, long bsize)
+{
+	bdiffparam_t bdp;
+	bdp.bsize = bsize;
+	xdemitcb_t ecb;
+	ecb.priv = cast(void*) cast(size_t) 1;
+	ecb.outf = &fdOut;
+	return xdl_bdiff(&a.mf, &b.mf, &bdp, &ecb);
+}
+
+int doRaBDiff(ref MmFile a, ref MmFile b)
+{
+	xdemitcb_t ecb;
+	ecb.priv = cast(void*) cast(size_t) 1;
+	ecb.outf = &fdOut;
+	return xdl_rabdiff(&a.mf, &b.mf, &ecb);
+}
+
+int doBPatch(ref MmFile base, ref MmFile binPatch)
+{
+	xdemitcb_t ecb;
+	ecb.priv = cast(void*) cast(size_t) 1;
+	ecb.outf = &fdOut;
+	return xdl_bpatch(&base.mf, &binPatch.mf, &ecb);
+}
+
+// ------------------------------
+// CLI
+// ------------------------------
+enum Cmd
+{
+	diff,
+	patch,
+	bdiff,
+	rabdiff,
+	bpatch
+}
+
+private Cmd parseCmd(string s)
+{
+	final switch (s)
+	{
+	case "diff":
+		return Cmd.diff;
+	case "patch":
+		return Cmd.patch;
+	case "bdiff":
+		return Cmd.bdiff;
+	case "rabdiff":
+		return Cmd.rabdiff;
+	case "bpatch":
+		return Cmd.bpatch;
+	}
+}
+
+/// Короткая справка
+void printUsage(string prg)
+{
+	stderr.writefln(
+		"use: %1$s diff   [-C N]  FROM TO\n" ~
+			"     %1$s patch           ORIG PATCH\n" ~
+			"     %1$s bdiff  [-B N]   FROM TO\n" ~
+			"     %1$s rabdiff         FROM TO\n" ~
+			"     %1$s bpatch          ORIG PATCH\n",
+			prg);
+}
+
+/// Парсинг подкоманды + её опций. Возвращаем уже «очищенный» список позиционных.
+struct Parsed
+{
+	Cmd cmd;
+	long ctxlen = 3; // для diff
+	long bsize = 16; // для bdiff
+	string[] positional; // оставшиеся позиционные (пути)
+}
+
+Parsed parseArgs(string[] args)
+{
+	enforce(args.length >= 2, "no subcommand");
+	auto sub = args[1];
+	auto cmd = parseCmd(sub);
+
+	long ctxlen = 3;
+	long bsize = 16;
+	bool helpWanted = false;
+
+	// Опции и позиционные ТОЛЬКО после подкоманды
+	string[] optArgs = args.length > 2 ? args[2 .. $].dup : [];
+
+	// getopt выкинет опции из optArgs и оставит только позиционные
+	auto r = getopt(optArgs,
+		"h|help", &helpWanted,
+		"C", &ctxlen, // актуально для `diff`
+		"B", &bsize // актуально для `bdiff`
+
+		
+
+	);
+	enforce(!helpWanted, "help");
+
+	Parsed p;
+	p.cmd = cmd;
+	p.ctxlen = ctxlen;
+	p.bsize = bsize;
+	p.positional = optArgs; // здесь уже только пути
+	return p;
+}
+
+int main(string[] args)
+{
+	// 1) Парсим
+	Parsed p;
+	try
+	{
+		p = parseArgs(args);
+	}
+	catch (Exception)
+	{
+		printUsage(args[0]);
+		return 1;
+	}
+	if (p.positional.length != 2)
+	{
+		// каждая подкоманда требует ровно 2 пути
+		printUsage(args[0]);
+		return 1;
+	}
+	auto p1 = p.positional[0];
+	auto p2 = p.positional[1];
+
+	// 2) Аллокатор libxdiff
+	installAllocator();
+
+	// 3) Готовим входы
+	auto mf1 = MmFile.create();
+	scope (exit)
+		mf1.deinit();
+	auto mf2 = MmFile.create();
+	scope (exit)
+		mf2.deinit();
+
+	try
+	{
+		loadMmFile(mf1, p1);
+		loadMmFile(mf2, p2);
+	}
+	catch (Exception e)
+	{
+		stderr.writeln(e.msg);
+		return 1;
+	}
+
+	// 4) Запускаем действие
+	int rc = 0;
+	final switch (p.cmd)
+	{
+	case Cmd.diff:
+		rc = doDiff(mf1, mf2, p.ctxlen);
+		break;
+	case Cmd.patch:
+		rc = doPatch(mf1, mf2, XDL_PATCH_NORMAL);
+		break;
+	case Cmd.bdiff:
+		rc = doBDiff(mf1, mf2, p.bsize);
+		break;
+	case Cmd.rabdiff:
+		rc = doRaBDiff(mf1, mf2);
+		break;
+	case Cmd.bpatch:
+		rc = doBPatch(mf1, mf2);
+		break;
+	}
+	return rc < 0 ? 2 : 0;
 }
diff --git a/source/libxdiff/init.d b/source/libxdiff/init.d
deleted file mode 100644
index 546679c..0000000
--- a/source/libxdiff/init.d
+++ /dev/null
@@ -1,70 +0,0 @@
-module libxdiff.init;
-
-import xdiff;
-
-import core.stdc.stdlib : malloc, free, realloc;
-import std.exception : enforce;
-import core.stdc.errno : errno;
-import core.stdc.string : strerror;
-import std.string : fromStringz;
-import std.conv : to;
-
-private __gshared bool _allocatorReady = false;
-package(libxdiff) alias ByteArray = const(ubyte)[];
-
-extern (C)
-{
-	private void* wrap_malloc(void*, uint size)
-	{
-		return malloc(size);
-	}
-
-	private void wrap_free(void*, void* p)
-	{
-		free(p);
-	}
-
-	private void* wrap_realloc(void*, void* p, uint size)
-	{
-		return realloc(p, size);
-	}
-}
-
-private void setAllocator()
-{
-	if (_allocatorReady)
-		return;
-
-	memallocator_t m = {null, &wrap_malloc, &wrap_free, &wrap_realloc};
-
-	enforce(xdl_set_allocator(&m) == 0,
-		"xdl_set_allocator failed: " ~ strerror(errno).fromStringz);
-	_allocatorReady = true;
-}
-
-mmfile_t initMmfile(size_t len)
-{
-	setAllocator();
-	mmfile_t mf;
-	enforce(xdl_init_mmfile(&mf, len.to!long, XDL_MMF_ATOMIC) == 0,
-		"xdl_init_mmfile failed: " ~ strerror(errno).fromStringz);
-	return mf;
-}
-
-abstract class MM
-{
-protected:
-	mmfile_t _inner;
-public:
-	final @property size_t size()
-	{
-		return xdl_mmfile_size(&_inner).to!size_t;
-	}
-
-	// Проверка «компактности» — содержимое лежит в одном блоке
-	// (важно для бинарных функций, которым нужно сплошное непрерывное представление).
-	final bool isCompact() const
-	{
-		return xdl_mmfile_iscompact(cast(mmfile_t*)&_inner) != 0;
-	}
-}
diff --git a/source/libxdiff/mmblocks.d b/source/libxdiff/mmblocks.d
deleted file mode 100644
index 8ec975a..0000000
--- a/source/libxdiff/mmblocks.d
+++ /dev/null
@@ -1,41 +0,0 @@
-module libxdiff.mmblocks;
-
-import xdiff;
-
-import libxdiff.init;
-
-import std.exception : enforce;
-import core.stdc.errno : errno;
-import core.stdc.string : strerror;
-import std.string : fromStringz;
-import std.conv : to;
-
-private enum DEFAULT_BSIZE = 8 * 1024;
-
-final class MMBlocks : MM
-{
-public:
-	this()
-	{
-		_inner = initMmfile(DEFAULT_BSIZE);
-	}
-
-	package(libxdiff) mmfile_t* ptr() @trusted
-	{
-		return &_inner;
-	}
-
-	const(ubyte)[] asSlice() @trusted
-	{
-		enforce(isCompact(), "MMFile must be compact for asSliceConst");
-		auto h = _inner.head;
-		return h is null || h.size <= 0 ? [] : (cast(const(ubyte)*) h.ptr)[0 .. h.size.to!size_t];
-	}
-
-	override string toString() const @trusted
-	{
-		enforce(isCompact(), "MMFile must be compact for asSliceConst");
-		auto h = _inner.head;
-		return h is null || h.size <= 0 ? [] : fromStringz(cast(const char*) h.ptr).idup;
-	}
-}
diff --git a/source/libxdiff/mmfile.d b/source/libxdiff/mmfile.d
deleted file mode 100644
index 1bcbca4..0000000
--- a/source/libxdiff/mmfile.d
+++ /dev/null
@@ -1,79 +0,0 @@
-module libxdiff.mmfile;
-
-import xdiff;
-
-import libxdiff.init;
-import libxdiff.mmblocks;
-
-import std.exception : enforce;
-import core.stdc.errno : errno;
-import core.stdc.string : strerror;
-import std.string : fromStringz;
-import std.conv : to;
-import std.string : join, representation;
-
-final class MMFile : MM
-{
-private:
-	void _write(ByteArray data)
-	{
-		_inner = initMmfile(0);
-
-		if (data.length > 0)
-		{
-			auto length = data.length.to!long;
-			auto wrote = xdl_write_mmfile(&_inner, data.ptr, length);
-			enforce(wrote == length,
-				"xdl_write_mmfile wrote less than requested: " ~ strerror(errno).fromStringz);
-		}
-	}
-
-public:
-	this(ByteArray data)
-	{
-		_write(data);
-	}
-
-	this(string data)
-	{
-		_write(data.representation);
-	}
-
-	this(string[] data)
-	{
-		_write(data.join('\n').representation);
-	}
-
-	~this()
-	{
-		if (_inner.head !is null)
-			xdl_free_mmfile(&_inner);
-	}
-
-	MMBlocks computePatch(ref MMFile other, long ctxlen = 3)
-	{
-		auto patch = new MMBlocks();
-
-		extern (C) int emitToPatch(void* priv, mmbuffer_t* bufs, int num)
-		{
-			auto target = cast(MMBlocks) priv;
-			foreach (i; 0 .. num)
-			{
-				mmbuffer_t* buf = &bufs[i];
-				long written = xdl_writem_mmfile(target.ptr(), buf, 1);
-				if (written < 0 || written != buf.size)
-					return -1;
-			}
-			return 0;
-		}
-
-		xpparam_t xpp = {0};
-		xdemitconf_t xec = {ctxlen};
-		xdemitcb_t ecb = {cast(void*) patch, &emitToPatch};
-
-		enforce(xdl_diff(&_inner, &other._inner, &xpp, &xec, &ecb) == 0,
-			"xdl_diff failed: " ~ strerror(errno).fromStringz);
-
-		return patch;
-	}
-}
diff --git a/source/libxdiff/package.d b/source/libxdiff/package.d
deleted file mode 100644
index 3e27fe2..0000000
--- a/source/libxdiff/package.d
+++ /dev/null
@@ -1,4 +0,0 @@
-module libxdiff;
-
-public import libxdiff.mmfile;
-public import libxdiff.mmblocks;