diff --git a/mercurial/util.py b/mercurial/util.py
--- a/mercurial/util.py
+++ b/mercurial/util.py
@@ -3197,5 +3197,50 @@ class _noopengine(compressionengine):
 
 compengines.register(_noopengine())
 
+class _zstdengine(compressionengine):
+    def name(self):
+        return 'zstd'
+
+    @propertycache
+    def _module(self):
+        # Not all installs have the zstd module available. So defer importing
+        # until first access.
+        try:
+            from . import zstd
+            # Force delayed import.
+            zstd.__version__
+            return zstd
+        except ImportError:
+            return None
+
+    def available(self):
+        return bool(self._module)
+
+    def bundletype(self):
+        return 'zstd', 'ZS'
+
+    def compressstream(self, it, opts=None):
+        opts = opts or {}
+        # zstd level 3 is almost always significantly faster than zlib
+        # while providing no worse compression. It strikes a good balance
+        # between speed and compression.
+        level = opts.get('level', 3)
+
+        zstd = self._module
+        z = zstd.ZstdCompressor(level=level).compressobj()
+        for chunk in it:
+            data = z.compress(chunk)
+            if data:
+                yield data
+
+        yield z.flush()
+
+    def decompressorreader(self, fh):
+        zstd = self._module
+        dctx = zstd.ZstdDecompressor()
+        return chunkbuffer(dctx.read_from(fh))
+
+compengines.register(_zstdengine())
+
 # convenient shortcut
 dst = debugstacktrace
diff --git a/tests/test-bundle-type.t b/tests/test-bundle-type.t
--- a/tests/test-bundle-type.t
+++ b/tests/test-bundle-type.t
@@ -35,17 +35,21 @@ bundle w/o type option
 
 test bundle types
 
-  $ for t in "None" "bzip2" "gzip" "none-v2" "v2" "v1" "gzip-v1"; do
-  >   echo % test bundle type $t
-  >   hg init t$t
+  $ testbundle() {
+  >   echo % test bundle type $1
+  >   hg init t$1
   >   cd t1
-  >   hg bundle -t $t ../b$t ../t$t
-  >   f -q -B6 -D ../b$t; echo
-  >   cd ../t$t
-  >   hg debugbundle ../b$t
-  >   hg debugbundle --spec ../b$t
+  >   hg bundle -t $1 ../b$1 ../t$1
+  >   f -q -B6 -D ../b$1; echo
+  >   cd ../t$1
+  >   hg debugbundle ../b$1
+  >   hg debugbundle --spec ../b$1
   >   echo
   >   cd ..
+  > }
+
+  $ for t in "None" "bzip2" "gzip" "none-v2" "v2" "v1" "gzip-v1"; do
+  >   testbundle $t
   > done
   % test bundle type None
   searching for changes
@@ -106,6 +110,38 @@ test bundle types
   c35a0f9217e65d1fdb90c936ffa7dbe679f83ddf
   gzip-v1
   
+#if zstd
+
+  $ for t in "zstd" "zstd-v2"; do
+  >   testbundle $t
+  > done
+  % test bundle type zstd
+  searching for changes
+  1 changesets found
+  HG20\x00\x00 (esc)
+  Stream params: sortdict([('Compression', 'ZS')])
+  changegroup -- "sortdict([('version', '02'), ('nbchanges', '1')])"
+      c35a0f9217e65d1fdb90c936ffa7dbe679f83ddf
+  zstd-v2
+  
+  % test bundle type zstd-v2
+  searching for changes
+  1 changesets found
+  HG20\x00\x00 (esc)
+  Stream params: sortdict([('Compression', 'ZS')])
+  changegroup -- "sortdict([('version', '02'), ('nbchanges', '1')])"
+      c35a0f9217e65d1fdb90c936ffa7dbe679f83ddf
+  zstd-v2
+  
+#else
+
+zstd is a valid engine but isn't available
+
+  $ hg -R t1 bundle -a -t zstd irrelevant.hg
+  abort: compression engine zstd could not be loaded
+  [255]
+
+#endif
 
 test garbage file