diff --git a/configure b/configure
index 2c7b62b..99b5358 100755
--- a/configure
+++ b/configure
@@ -4809,12 +4809,18 @@
 
 if test "$have_zstd" = "yes"; then
    echo "zstd library: yes"
+   antispam_libs="$antispam_libs -lzstd"
+   defs="$defs -DHAVE_ZSTD"
+
+   if test "$(which zstd)" = ""; then echo "Error: cannot find the zstd binary"; exit 1; fi
+
+   zstd_magic=$(echo this is a test | zstd | hexdump -C | awk '/00000000/{print "ntohl(0x"$2$3$4$5 ")"}')
+
 
 cat >>confdefs.h <<_ACEOF
-#define HAVE_ZSTD 1
+#define ZSTD_DETECTED_MAGICNUMBER $zstd_magic
 _ACEOF
 
-   antispam_libs="$antispam_libs -lzstd"
 fi
 
 if test "$have_zip" = "yes"; then
diff --git a/configure.in b/configure.in
index 5eea65e..5c6f27c 100644
--- a/configure.in
+++ b/configure.in
@@ -441,8 +441,14 @@
 
 if test "$have_zstd" = "yes"; then
    echo "zstd library: yes"
-   AC_DEFINE_UNQUOTED(HAVE_ZSTD, 1, [libzstd support])
    antispam_libs="$antispam_libs -lzstd"
+   defs="$defs -DHAVE_ZSTD"
+
+   if test "$(which zstd)" = ""; then echo "Error: cannot find the zstd binary"; exit 1; fi
+
+   zstd_magic=$(echo this is a test | zstd | hexdump -C | awk '/00000000/{print "ntohl(0x"$2$3$4$5 ")"}')
+
+   AC_DEFINE_UNQUOTED(ZSTD_DETECTED_MAGICNUMBER, $zstd_magic, [detected zstd magic number])
 fi
 
 if test "$have_zip" = "yes"; then
diff --git a/piler-config.h.in b/piler-config.h.in
index a9915fc..72144ac 100644
--- a/piler-config.h.in
+++ b/piler-config.h.in
@@ -26,9 +26,8 @@
 
 #undef HAVE_LIBWRAP
 
-#undef HAVE_ZSTD
-
 #undef HAVE_TWEAK_SENT_TIME
 
 #undef HAVE_SUPPORT_FOR_COMPAT_STORAGE_LAYOUT
 
+#undef ZSTD_DETECTED_MAGICNUMBER
diff --git a/src/archive.c b/src/archive.c
index 3160b6a..6b23f30 100644
--- a/src/archive.c
+++ b/src/archive.c
@@ -20,6 +20,10 @@
 #include <assert.h>
 #include <piler.h>
 
+#ifdef HAVE_ZSTD
+   #include <zstd.h>
+#endif
+
 
 
 void zerr(int ret){
@@ -131,12 +135,53 @@
 }
 
 
+int zstd_inf(unsigned char *in, int len, int mode, char **buffer, FILE *dest){
+   size_t dSize;
+   unsigned long long const rSize = ZSTD_getDecompressedSize(in, len);
+
+   if(rSize == 0)
+      return Z_DATA_ERROR;
+
+   if(mode == WRITE_TO_STDOUT){
+      void* const rBuff = malloc((size_t)rSize);
+      if(!rBuff) return Z_MEM_ERROR;
+
+      dSize = ZSTD_decompress(rBuff, rSize, in, len);
+
+      if(dSize != rSize){
+         printf("error decoding buffer: %s\n", ZSTD_getErrorName(dSize));
+         return Z_DATA_ERROR;
+      }
+
+      fwrite(rBuff, 1, dSize, dest);
+
+      free(rBuff);
+   }
+   else {
+      *buffer = malloc((size_t)rSize);
+      if(!*buffer) return Z_MEM_ERROR;
+      memset(*buffer, 0, rSize);
+
+      dSize = ZSTD_decompress(*buffer, rSize, in, len);
+      if(dSize != rSize){
+         printf("error decoding buffer: %s\n", ZSTD_getErrorName(dSize));
+         return Z_DATA_ERROR;
+      }
+   }
+
+   return Z_OK;
+}
+
+
+
 int retrieve_file_from_archive(char *filename, int mode, char **buffer, FILE *dest, struct __config *cfg){
    int rc=0, n, olen, tlen, len, fd=-1;
    unsigned char *s=NULL, *addr=NULL, inbuf[REALLYBIGBUFSIZE];
    struct stat st;
    EVP_CIPHER_CTX ctx;
-
+#ifdef HAVE_ZSTD
+   unsigned long magic;
+#endif
 
    if(filename == NULL) return 1;
 
@@ -188,11 +233,39 @@
 
 
       tlen += olen;
-      rc = inf(s, tlen, mode, buffer, dest);
+
+      if(st.st_size > 4){
+         memcpy(&magic, addr, 4);
+      #ifdef HAVE_ZSTD
+         if(magic == ZSTD_DETECTED_MAGICNUMBER){
+            rc = zstd_inf(s, tlen, mode, buffer, dest);
+         }
+         else {
+      #endif
+            rc = inf(s, tlen, mode, buffer, dest);
+      #ifdef HAVE_ZSTD
+         }
+      #endif
+      }
    }
    else {
       addr = mmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
-      rc = inf(addr, st.st_size, mode, buffer, dest);
+
+      if(st.st_size > 4){
+      #ifdef HAVE_ZSTD
+         memcpy(&magic, addr, 4);
+
+         if(magic == ZSTD_DETECTED_MAGICNUMBER){
+            rc = zstd_inf(addr, st.st_size, mode, buffer, dest);
+         }
+         else {
+      #endif
+            rc = inf(addr, st.st_size, mode, buffer, dest);
+      #ifdef HAVE_ZSTD
+         }
+      #endif
+      }
+
       munmap(addr, st.st_size);
    }
 
diff --git a/src/store.c b/src/store.c
index f06341d..d051ca2 100644
--- a/src/store.c
+++ b/src/store.c
@@ -97,22 +97,24 @@
 
    if(dst == NULL){
       munmap(addr, len);
-      syslog(LOG_PRIORITY, "%s: cannot malloc for zstd buffer", sdata->ttmpfile);
+      syslog(LOG_PRIORITY, "%s: ERROR: cannot malloc for zstd buffer", sdata->ttmpfile);
       return ret;
    }
 
-   size_t const cSize = ZSTD_compress(dst, destlen, addr, len, 1);
+   size_t const cSize = ZSTD_compress(dst, dstlen, addr, len, 1);
    if(ZSTD_isError(cSize)){
-      syslog(LOG_PRIORITY, "%s: error zstd compressing: %s", sdata->ttmpfile, ZSTD_getErrorName(cSize));
+      syslog(LOG_PRIORITY, "%s: ERROR: zstd compressing: %s", sdata->ttmpfile, ZSTD_getErrorName(cSize));
       rc = ERR;
    }
+
+   dstlen = cSize;
 #else
    dstlen = compressBound(len);
    dst = malloc(dstlen);
 
    if(dst == NULL){
       munmap(addr, len);
-      syslog(LOG_PRIORITY, "%s: cannot malloc for z buffer", sdata->ttmpfile);
+      syslog(LOG_PRIORITY, "%s: ERROR: cannot malloc for z buffer", sdata->ttmpfile);
       return ret;
    }