diff --git a/src/blackcore/db/databaseutils.cpp b/src/blackcore/db/databaseutils.cpp
index a2a83c09c..6f88b5753 100644
--- a/src/blackcore/db/databaseutils.cpp
+++ b/src/blackcore/db/databaseutils.cpp
@@ -12,6 +12,7 @@
 #include "blackcore/webdataservices.h"
 #include "blackmisc/logmessage.h"
 #include "blackmisc/fileutils.h"
+#include "blackmisc/compressutils.h"
 
 using namespace BlackMisc;
 using namespace BlackMisc::Json;
@@ -344,16 +345,10 @@ namespace BlackCore
                     if (!ok) break; // malformed size
                     if (size < 1) break;
 
-                    // Length header, unsigned, big-endian, 32-bit integer
-                    QByteArray lengthHeader;
-                    QDataStream stream(&lengthHeader, QIODevice::WriteOnly);
-                    stream.setByteOrder(QDataStream::BigEndian);
-                    stream << size;
-
                     QByteArray ba;
                     ba.append(content.mid(contentIndex));
                     ba = QByteArray::fromBase64(ba);
-                    ba.insert(0, lengthHeader); // adding 4 bytes length header
+                    ba.insert(0, CCompressUtils::lengthHeader(size)); // adding 4 bytes length header
                     byteData = qUncompress(ba);
                 }
                 while (false);
@@ -399,13 +394,13 @@ namespace BlackCore
         QHttpPart CDatabaseUtils::getJsonTextMultipart(const QJsonObject &json, bool compress)
         {
             const QByteArray bytes(QJsonDocument(json).toJson(QJsonDocument::Compact));
-            return getJsonTextMultipart(bytes, compress);
+            return CDatabaseUtils::getJsonTextMultipart(bytes, compress);
         }
 
         QHttpPart CDatabaseUtils::getJsonTextMultipart(const QJsonArray &json, bool compress)
         {
             const QByteArray bytes(QJsonDocument(json).toJson(QJsonDocument::Compact));
-            return getJsonTextMultipart(bytes, compress);
+            return CDatabaseUtils::getJsonTextMultipart(bytes, compress);
         }
 
         QHttpPart CDatabaseUtils::getJsonTextMultipart(const QByteArray &bytes, bool compress)
diff --git a/src/blackmisc/compressutils.cpp b/src/blackmisc/compressutils.cpp
new file mode 100644
index 000000000..d88ff86d8
--- /dev/null
+++ b/src/blackmisc/compressutils.cpp
@@ -0,0 +1,95 @@
+/* Copyright (C) 2018
+ * swift project Community / Contributors
+ *
+ * This file is part of swift project. It is subject to the license terms in the LICENSE file found in the top-level
+ * directory of this distribution and at http://www.swift-project.org/license.html. No part of swift project,
+ * including this file, may be copied, modified, propagated, or distributed except according to the terms
+ * contained in the LICENSE file.
+ */
+
+#include "compressutils.h"
+#include "blackconfig/buildconfig.h"
+#include "fileutils.h"
+#include "directoryutils.h"
+#include "stringutils.h"
+
+#include <QFileInfo>
+#include <QProcess>
+
+using namespace BlackConfig;
+
+namespace BlackMisc
+{
+    QByteArray CCompressUtils::lengthHeader(qint32 size)
+    {
+        // Length header, unsigned, big-endian, 32-bit integer
+        QByteArray lengthHeader;
+        QDataStream stream(&lengthHeader, QIODevice::WriteOnly);
+        stream.setByteOrder(QDataStream::BigEndian);
+        stream << size;
+        Q_ASSERT_X(lengthHeader.size() == 4, Q_FUNC_INFO, "Wrong header size");
+        return lengthHeader;
+    }
+
+    bool CCompressUtils::zip7Uncompress(const QString &file, const QString &directory, bool wait, QStringList *stdOutAndError)
+    {
+        const QFileInfo fi(file);
+        if (!fi.exists()) { return false; }
+
+        const bool win = CBuildConfig::isRunningOnWindowsNtPlatform();
+        const QString d =
+            d.isEmpty() ? d :
+            win ? CFileUtils::toWindowsLocalPath(directory) : directory;
+        const QString f = win ? CFileUtils::toWindowsLocalPath(file) : file;
+
+        // 7za.exe x -o"P:\Temp\XPlane" c:\Users\Foo\Downloads\xswiftbus-allos-0.8.4.802111947.7z
+        const QString cmd = win ? QStringLiteral("7za.exe") : QStringLiteral("7za");
+        QStringList args;
+        args << "x";
+        args << "-aoa";
+        if (!d.isEmpty()) { args << "-o" + d; }
+        args << f;
+
+        if (wait)
+        {
+            QProcess zipProcess;
+            zipProcess.start(cmd, args);
+            const bool finished = zipProcess.waitForFinished();
+            if (zipProcess.exitStatus() != QProcess::NormalExit) { return false; }
+            if (!finished) { return false; }
+            const int r = zipProcess.exitCode();
+            const QString pStdout = zipProcess.readAllStandardOutput();
+            const QString pStderr = zipProcess.readAllStandardError();
+            if (stdOutAndError)
+            {
+                stdOutAndError->clear();
+                stdOutAndError->push_back(pStdout);
+                stdOutAndError->push_back(pStderr);
+            }
+
+            return r == 0;
+        }
+        else
+        {
+            QProcess *p = new QProcess();
+            p->start(cmd, args);
+            return true;
+        }
+    }
+
+    bool CCompressUtils::hasZip7()
+    {
+        // just display info
+        const bool win = CBuildConfig::isRunningOnWindowsNtPlatform();
+        const QString cmd = win ? QStringLiteral("7za.exe") : QStringLiteral("7za");
+        QStringList args;
+        args << "i";
+        QProcess zipProcess;
+        zipProcess.start(cmd, args);
+        const bool finished = zipProcess.waitForFinished();
+        if (zipProcess.exitStatus() != QProcess::NormalExit) { return false; }
+        if (!finished) { return false; }
+        const int r = zipProcess.exitCode();
+        return r == 0;
+    }
+} // ns
diff --git a/src/blackmisc/compressutils.h b/src/blackmisc/compressutils.h
new file mode 100644
index 000000000..66b0b0e80
--- /dev/null
+++ b/src/blackmisc/compressutils.h
@@ -0,0 +1,43 @@
+/* Copyright (C) 2018
+ * swift project Community / Contributors
+ *
+ * This file is part of swift project. It is subject to the license terms in the LICENSE file found in the top-level
+ * directory of this distribution and at http://www.swift-project.org/license.html. No part of swift project,
+ * including this file, may be copied, modified, propagated, or distributed except according to the terms
+ * contained in the LICENSE file.
+ */
+
+//! \file
+
+#ifndef BLACKMISC_COMPRESSUTILS_H
+#define BLACKMISC_COMPRESSUTILS_H
+
+#include "blackmisc/blackmiscexport.h"
+#include <QByteArray>
+#include <QStringList>
+
+namespace BlackMisc
+{
+    //! Compress utilities
+    class BLACKMISC_EXPORT CCompressUtils
+    {
+    public:
+        //! Length header
+        //! \remark 4 bytes -> 32bit
+        static QByteArray lengthHeader(qint32 size);
+
+        //! Unzip my using 7zip
+        //! \remark relies on external 7zip command line
+        static bool zip7Uncompress(const QString &file, const QString &directory, bool wait, QStringList *stdOutAndError = nullptr);
+
+        //! External program existing?
+        //! \remark relies on external 7zip command line
+        static bool hasZip7();
+
+    private:
+        //! Ctor
+        CCompressUtils() {}
+    };
+} // ns
+
+#endif // guard