diff --git a/contrib/long_distance_matching/ldm.c b/contrib/long_distance_matching/ldm.c
index 34118c81..c8051ea4 100644
--- a/contrib/long_distance_matching/ldm.c
+++ b/contrib/long_distance_matching/ldm.c
@@ -1,9 +1,25 @@
 #include <stdlib.h>
 #include <string.h>
 #include <stdint.h>
+#include <stdio.h>
 
 #include "ldm.h"
 
+#define LDM_MEMORY_USAGE 14
+#define LDM_HASHLOG (LDM_MEMORY_USAGE-2)
+#define LDM_HASHTABLESIZE (1 << (LDM_MEMORY_USAGE))
+#define LDM_HASHTABLESIZE_U32 ((LDM_HASHTABLESIZE) >> 2)
+#define LDM_HASH_SIZE_U32 (1 << (LDM_HASHLOG))
+
+#define WINDOW_SIZE (1 << 20)
+#define HASH_SIZE 4
+#define MINMATCH 4
+
+#define ML_BITS 4
+#define ML_MASK ((1U<<ML_BITS)-1)
+#define RUN_BITS (8-ML_BITS)
+#define RUN_MASK ((1U<<RUN_BITS)-1)
+
 typedef  uint8_t BYTE;
 typedef uint16_t U16;
 typedef uint32_t U32;
@@ -12,31 +28,321 @@ typedef uint64_t U64;
 
 typedef uint64_t tag;
 
+static unsigned LDM_isLittleEndian(void)
+{
+    const union { U32 u; BYTE c[4]; } one = { 1 };
+    return one.c[0];
+}
+
+static U16 LDM_read16(const void *memPtr) {
+  U16 val;
+  memcpy(&val, memPtr, sizeof(val));
+  return val;
+}
+
+static U16 LDM_readLE16(const void *memPtr) {
+  if (LDM_isLittleEndian()) {
+    return LDM_read16(memPtr);
+  } else {
+    const BYTE *p = (const BYTE *)memPtr;
+    return (U16)((U16)p[0] + (p[1] << 8));
+  }
+}
+
+static void LDM_write32(void *memPtr, U32 value) {
+  memcpy(memPtr, &value, sizeof(value));
+}
+
+static void LDM_write16(void *memPtr, U16 value) {
+  memcpy(memPtr, &value, sizeof(value));
+}
+
+static void LDM_writeLE16(void *memPtr, U16 value) {
+  if (LDM_isLittleEndian()) {
+    LDM_write16(memPtr, value);
+  } else {
+    BYTE* p = (BYTE*)memPtr;
+    p[0] = (BYTE) value;
+    p[1] = (BYTE)(value>>8);
+  }
+}
+
+
+
+static U32 LDM_read32(const void *ptr) {
+  return *(const U32 *)ptr;
+}
+
+static void LDM_copy8(void *dst, const void *src) {
+  memcpy(dst, src, 8);
+}
+
+static void LDM_wild_copy(void *dstPtr, const void *srcPtr, void *dstEnd) {
+  BYTE *d = (BYTE *)dstPtr;
+  const BYTE *s = (const BYTE *)srcPtr;
+  BYTE * const e = (BYTE *)dstEnd;
+
+  do {
+    LDM_copy8(d, s);
+    d += 8;
+    s += 8;
+  } while (d < e);
+
+}
+
 struct hash_entry {
   U64 offset;
   tag t;
 };
 
-size_t LDM_compress(const char *source, char *dest, size_t source_size, size_t max_dest_size) {
-  // max_dest_size >= source_size
-
-
-  /**
-   * Loop:
-   *  Find match at position k (hash next n bytes, rolling hash)
-   *  Compute match length
-   *  Output literal length: k (sequences of 4 + (k-4) bytes)
-   *  Output match length
-   *  Output literals
-   *  Output offset
-   */
-
-  memcpy(dest, source, source_size);
-  return source_size;
+static U32 LDM_hash(U32 sequence) {
+  return ((sequence * 2654435761U) >> ((MINMATCH*8)-LDM_HASHLOG));
 }
 
-size_t LDM_decompress(const char *source, char *dest, size_t compressed_size, size_t max_decompressed_size) {
-  memcpy(dest, source, compressed_size);
+static U32 LDM_hash_position(const void * const p) {
+  return LDM_hash(LDM_read32(p));
+}
+
+static U64 find_best_match(tag t, U64 offset) {
+  return 0;
+}
+
+static void LDM_put_position_on_hash(const BYTE *p, U32 h, void *tableBase,
+                                     const BYTE *srcBase) {
+  U32 *hashTable = (U32 *) tableBase;
+  hashTable[h] = (U32)(p - srcBase);
+}
+
+static void LDM_put_position(const BYTE *p, void *tableBase,
+                             const BYTE *srcBase) {
+  U32 const h = LDM_hash_position(p);
+  LDM_put_position_on_hash(p, h, tableBase, srcBase);
+}
+
+static const BYTE *LDM_get_position_on_hash(
+    U32 h, void *tableBase, const BYTE *srcBase) {
+  const U32 * const hashTable = (U32*)tableBase;
+  return hashTable[h] + srcBase;
+}
+
+static BYTE LDM_read_byte(const void *memPtr) {
+  BYTE val;
+  memcpy(&val, memPtr, 1);
+  return val;
+}
+
+static unsigned LDM_count(const BYTE *pIn, const BYTE *pMatch,
+                          const BYTE *pInLimit) {
+  const BYTE * const pStart = pIn;
+  while (pIn < pInLimit - 1) {
+    BYTE const diff = LDM_read_byte(pMatch) ^ LDM_read_byte(pIn);
+    if (!diff) {
+      pIn++;
+      pMatch++;
+      continue;
+    }
+    return (unsigned)(pIn - pStart);
+  }
+  return (unsigned)(pIn - pStart);
+}
+
+
+size_t LDM_compress(void const *source, void *dest, size_t source_size,
+                    size_t max_dest_size) {
+  const BYTE * const istart = (const BYTE*)source;
+  const BYTE *ip = istart;
+  const BYTE * const iend = istart + source_size;
+  const BYTE *ilimit = iend - HASH_SIZE;
+  const BYTE * const matchlimit = iend - HASH_SIZE;
+  BYTE *op = (BYTE*) dest;
+  U32 hashTable[LDM_HASHTABLESIZE_U32];
+  memset(hashTable, 0, sizeof(hashTable));
+
+  const BYTE *anchor = (const BYTE *)source;
+//  struct LDM_cctx cctx;
+  size_t output_size = 0;
+
+  U32 forwardH;
+
+  /* Hash first byte: put into hash table */
+
+  LDM_put_position(ip, hashTable, istart);
+  ip++;
+  forwardH = LDM_hash_position(ip);
+
+  while (ip < ilimit) {
+    const BYTE *match;
+    BYTE *token;
+    /* Find a match */
+    {
+      const BYTE *forwardIp = ip;
+      unsigned step = 1;
+
+      do {
+        U32 const h = forwardH;
+        ip = forwardIp;
+        forwardIp += step;
+
+        match = LDM_get_position_on_hash(h, hashTable, istart);
+
+        forwardH = LDM_hash_position(forwardIp);
+        LDM_put_position_on_hash(ip, h, hashTable, istart);
+      } while (ip - match > WINDOW_SIZE ||
+               LDM_read32(match) != LDM_read32(ip));
+    }
+
+    /* Encode literals */
+    {
+      unsigned const litLength = (unsigned)(ip - anchor);
+      token = op++;
+
+      printf("Cur position: %zu\n", anchor - istart);
+      printf("LitLength %zu. (Match offset). %zu\n", litLength, ip - match);
+      /*
+      fwrite(match, 4, 1, stdout);
+      printf("\n");
+      */
+
+      if (litLength >= RUN_MASK) {
+        int len = (int)litLength - RUN_MASK;
+        *token = (RUN_MASK << ML_BITS);
+        for (; len >= 255; len -= 255) {
+          *op++ = (BYTE)len;
+        }
+      } else {
+        *token = (BYTE)(litLength << ML_BITS);
+      }
+
+      printf("Literals ");
+      fwrite(anchor, litLength, 1, stdout);
+      printf("\n");
+
+      LDM_wild_copy(op, anchor, op + litLength);
+      op += litLength;
+    }
+_next_match:
+    /* Encode offset */
+    {
+      LDM_writeLE16(op, (U16)(ip - match));
+      op += 2;
+    }
+
+    /* Encode Match Length */
+    {
+      unsigned matchCode;
+      matchCode = LDM_count(ip + MINMATCH, match + MINMATCH,
+                            matchlimit);
+
+      printf("Match length %zu\n", matchCode + MINMATCH);
+      fwrite(ip, MINMATCH + matchCode, 1, stdout);
+      printf("\n");
+      ip += MINMATCH + matchCode;
+      if (matchCode >= ML_MASK) {
+        *token += ML_MASK;
+        matchCode -= ML_MASK;
+        LDM_write32(op, 0xFFFFFFFF);
+        while (matchCode >= 4*0xFF) {
+          op += 4;
+          LDM_write32(op, 0xffffffff);
+          matchCode -= 4*0xFF;
+        }
+        op += matchCode / 255;
+        *op++ = (BYTE)(matchCode % 255);
+      } else {
+        *token += (BYTE)(matchCode);
+      }
+      printf("\n");
+    }
+
+    anchor = ip;
+
+    LDM_put_position(ip, hashTable, istart);
+    forwardH = LDM_hash_position(++ip);
+  }
+    /* Encode last literals */
+  {
+    /*
+    size_t const lastRun = (size_t)(iend - anchor);
+    printf("last run length: %zu, %zu %zu %zu %zu\n", lastRun, iend-istart,
+           anchor-istart, ip-istart, ilimit-istart);
+    if (lastRun >= RUN_MASK) {
+      size_t accumulator = lastRun - RUN_MASK;
+      *op++ = RUN_MASK << ML_BITS;
+      for(; accumulator >= 255; accumulator -= 255) {
+        *op++ = 255;
+      }
+      *op++ = (BYTE) accumulator;
+    } else {
+      *op++ = (BYTE)(lastRun << ML_BITS);
+    }
+    fwrite(anchor, lastRun, 1, stdout);
+    printf("^last run\n");
+    memcpy(op, anchor, lastRun);
+    op += lastRun;
+
+//    memcpy(dest + (ip - istart), ip, 1);
+//    */
+  }
+  return (op - (BYTE *)dest);
+}
+
+size_t LDM_decompress(void const *source, void *dest, size_t compressed_size,
+                      size_t max_decompressed_size) {
+  const BYTE *ip = (const BYTE *)source;
+  const BYTE * const iend = ip + compressed_size;
+  BYTE *op = (BYTE *)dest;
+  BYTE * const oend = op + max_decompressed_size;
+  BYTE *cpy;
+
+  while (ip < iend) {
+    size_t length;
+    const BYTE *match;
+    size_t offset;
+
+    /* get literal length */
+    unsigned const token = *ip++;
+    if ((length=(token >> ML_BITS)) == RUN_MASK) {
+      unsigned s;
+      do {
+        s = *ip++;
+        length += s;
+      } while (s == 255);
+    }
+    printf("Literal length: %zu\n", length);
+
+    /* copy literals */
+    cpy = op + length;
+    LDM_wild_copy(op, ip, cpy);
+    ip += length;
+    op = cpy;
+
+    /* get offset */
+    offset = LDM_readLE16(ip);
+    printf("Offset: %zu\n", offset);
+    ip += 2;
+    match = op - offset;
+ //   LDM_write32(op, (U32)offset);
+
+    /* get matchlength */
+    length = token & ML_MASK;
+    printf("Match length: %zu\n", length);
+    if (length == ML_MASK) {
+      unsigned s;
+      do {
+        s = *ip++;
+        length += s;
+      } while (s == 255);
+    }
+    length += MINMATCH;
+
+    /* copy match */
+    cpy = op + length;
+
+
+
+  }
+
+//  memcpy(dest, source, compressed_size);
   return compressed_size;
 }
 
diff --git a/contrib/long_distance_matching/ldm.h b/contrib/long_distance_matching/ldm.h
index d0151373..0aab6aa3 100644
--- a/contrib/long_distance_matching/ldm.h
+++ b/contrib/long_distance_matching/ldm.h
@@ -3,8 +3,10 @@
 
 #include <stddef.h>   /* size_t */
 
-size_t LDM_compress(const char *source, char *dest, size_t source_size, size_t max_dest_size);
+size_t LDM_compress(void const *source, void *dest, size_t source_size,
+                    size_t max_dest_size);
 
-size_t LDM_decompress(const char *source, char *dest, size_t compressed_size, size_t max_decompressed_size);
+size_t LDM_decompress(void const *source, void *dest, size_t compressed_size,
+                      size_t max_decompressed_size);
 
 #endif /* LDM_H */
diff --git a/contrib/long_distance_matching/main-ldm.c b/contrib/long_distance_matching/main-ldm.c
index bdcffb0f..8b97ce92 100644
--- a/contrib/long_distance_matching/main-ldm.c
+++ b/contrib/long_distance_matching/main-ldm.c
@@ -1,6 +1,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <sys/time.h>
 #include <sys/types.h>
 #include <sys/mman.h>
 #include <sys/stat.h>
@@ -13,6 +14,7 @@
 #define BUF_SIZE 16*1024  // Block size
 #define LDM_HEADER_SIZE 8
 #define DEBUG
+// #define ZSTD
 
 #if 0
 static size_t compress_file(FILE *in, FILE *out, size_t *size_in,
@@ -163,7 +165,7 @@ static size_t compress(const char *fname, const char *oname) {
     perror("lseek error");
     return 1;
  }
- 
+
  /* write a dummy byte at the last location */
  if (write(fdout, "", 1) != 1) {
      perror("write error");
@@ -186,9 +188,15 @@ static size_t compress(const char *fname, const char *oname) {
 
   /* Copy input file to output file */
 //  memcpy(dst, src, statbuf.st_size);
-  size_t size_out = ZSTD_compress(dst, statbuf.st_size, 
-                                  src, statbuf.st_size, 1);
-  printf("%25s : %6u -> %7u - %s (%.1f%%)\n", fname, 
+  #ifdef ZSTD
+    size_t size_out = ZSTD_compress(dst, statbuf.st_size,
+                                    src, statbuf.st_size, 1);
+  #else
+    size_t size_out = LDM_compress(src, dst, statbuf.st_size,
+                                   statbuf.st_size);
+  #endif
+  ftruncate(fdout, size_out);
+  printf("%25s : %6u -> %7u - %s (%.1f%%)\n", fname,
          (unsigned)statbuf.st_size, (unsigned)size_out, oname,
          (double)size_out / (statbuf.st_size) * 100);
 
@@ -225,7 +233,7 @@ static size_t decompress(const char *fname, const char *oname) {
     perror("lseek error");
     return 1;
   }
- 
+
   /* write a dummy byte at the last location */
   if (write(fdout, "", 1) != 1) {
     perror("write error");
@@ -249,9 +257,14 @@ static size_t decompress(const char *fname, const char *oname) {
   /* Copy input file to output file */
 //  memcpy(dst, src, statbuf.st_size);
 
-  size_t size_out = ZSTD_decompress(dst, statbuf.st_size, 
-                                    src, statbuf.st_size);
-
+  #ifdef ZSTD
+    size_t size_out = ZSTD_decompress(dst, statbuf.st_size,
+                                      src, statbuf.st_size);
+  #else
+    size_t size_out = LDM_decompress(src, dst, statbuf.st_size,
+                                     statbuf.st_size);
+  #endif
+  ftruncate(fdout, size_out);
 
   close(fdin);
   close(fdout);
@@ -315,20 +328,35 @@ int main(int argc, const char *argv[]) {
 	printf("ldm = [%s]\n", ldmFilename);
 	printf("dec = [%s]\n", decFilename);
 
+  struct timeval tv1, tv2;
   /* compress */
+  {
+  gettimeofday(&tv1, NULL);
   if (compress(inpFilename, ldmFilename)) {
       printf("Compress error");
       return 1;
   }
+  gettimeofday(&tv2, NULL);
+  printf("Total time = %f seconds\n",
+         (double) (tv2.tv_usec - tv1.tv_usec) / 1000000 +
+         (double) (tv2.tv_sec - tv1.tv_sec));
+  }
 
   /* decompress */
+
+  gettimeofday(&tv1, NULL);
   if (decompress(ldmFilename, decFilename)) {
       printf("Decompress error");
       return 1;
   }
+  gettimeofday(&tv2, NULL);
+  printf("Total time = %f seconds\n",
+        (double) (tv2.tv_usec - tv1.tv_usec) / 1000000 +
+        (double) (tv2.tv_sec - tv1.tv_sec));
 
   /* verify */
   verify(inpFilename, decFilename);
+  return 0;
 }
 
 #if 0