diff --git a/src/libstore/remote-store.cc b/src/libstore/remote-store.cc
index ea86ef05..c559b583 100644
--- a/src/libstore/remote-store.cc
+++ b/src/libstore/remote-store.cc
@@ -439,13 +439,24 @@ Path RemoteStore::addToStore(const string & name, const Path & _srcPath,
     try {
         conn->to.written = 0;
         conn->to.warn = true;
+
+        /* Increase the capacity because the 'filter' function could
+           issue more calls, which would otherwise deadlock. */
         connections->incCapacity();
-        {
-            Finally cleanup([&]() { connections->decCapacity(); });
+        Finally cleanup([&]() { connections->decCapacity(); });
+
+        std::unique_ptr<Source> source;
+
+        if (GET_PROTOCOL_MINOR(conn->daemonVersion) >= 22) {
+            source = sinkToSource([&](Sink & sink) {
+                dumpPath(srcPath, sink, filter);
+            });
+        } else
             dumpPath(srcPath, conn->to, filter);
-        }
+
         conn->to.warn = false;
-        conn->processStderr();
+        conn->processStderr(0, source ? &*source : nullptr);
+
     } catch (SysError & e) {
         /* Daemon closed while we were sending the path. Probably OOM
            or I/O error. */
diff --git a/src/libstore/worker-protocol.hh b/src/libstore/worker-protocol.hh
index 5ebdfaf1..b9bd5ca6 100644
--- a/src/libstore/worker-protocol.hh
+++ b/src/libstore/worker-protocol.hh
@@ -6,7 +6,7 @@ namespace nix {
 #define WORKER_MAGIC_1 0x6e697863
 #define WORKER_MAGIC_2 0x6478696f

-#define PROTOCOL_VERSION 0x115
+#define PROTOCOL_VERSION 0x116
 #define GET_PROTOCOL_MAJOR(x) ((x) & 0xff00)
 #define GET_PROTOCOL_MINOR(x) ((x) & 0x00ff)

diff --git a/src/nix-daemon/nix-daemon.cc b/src/nix-daemon/nix-daemon.cc
index 55611b7d..a3cce01f 100644
--- a/src/nix-daemon/nix-daemon.cc
+++ b/src/nix-daemon/nix-daemon.cc
@@ -349,22 +349,35 @@ static void performOp(TunnelLogger * logger, ref<LocalStore> store,
         }
         HashType hashAlgo = parseHashType(s);

-        TeeSource savedNAR(from);
-        RetrieveRegularNARSink savedRegular;
-
-        if (recursive) {
-            /* Get the entire NAR dump from the client and save it to
-               a string so that we can pass it to
-               addToStoreFromDump(). */
-            ParseSink sink; /* null sink; just parse the NAR */
-            parseDump(sink, savedNAR);
-        } else
-            parseDump(savedRegular, from);
+        if (GET_PROTOCOL_MINOR(clientVersion) < 22) {

-        logger->startWork();
-        if (!savedRegular.regular) throw Error("regular file expected");
-        Path path = store->addToStoreFromDump(recursive ? *savedNAR.data : savedRegular.s, baseName, recursive, hashAlgo);
-        logger->stopWork();
+            TeeSource savedNAR(from);
+            RetrieveRegularNARSink savedRegular;
+
+            if (recursive) {
+                /* Get the entire NAR dump from the client and save it to
+                   a string so that we can pass it to
+                   addToStoreFromDump(). */
+                ParseSink sink; /* null sink; just parse the NAR */
+                parseDump(sink, savedNAR);
+            } else
+                parseDump(savedRegular, from);
+
+            logger->startWork();
+            if (!savedRegular.regular) throw Error("regular file expected");
+            Path path = store->addToStoreFromDump(recursive ? *savedNAR.data : savedRegular.s, baseName, recursive, hashAlgo);
+            logger->stopWork();
+
+        } else {
+
+            logger->startWork();
+
+            // FIXME
+            store->addToStore(...);
+
+            logger->stopWork();
+
+        }

         to << path;
         break;