diff --git a/CalculatorCInterface/local_git_repository.cpp b/CalculatorCInterface/local_git_repository.cpp
new file mode 100644
index 0000000..3ad89f4
--- /dev/null
+++ b/CalculatorCInterface/local_git_repository.cpp
@@ -0,0 +1,113 @@
+#include "local_git_repository.h"
+
+#include <QDir>
+#include <QFile>
+#include <QTextStream>
+#include <QJsonDocument>
+#include <QByteArray>
+#include <QRegularExpression>
+#include <QRegularExpressionMatch>
+#include <QFile>
+
+LocalGitRepository::LocalGitRepository(QString const &localRepository)
+    : m_localRepository(localRepository)
+    , m_fileMenu("{}")
+    , m_fileMenuSize(-1) {
+}
+
+int32_t LocalGitRepository::GetFileMenuSize() const {
+    if (m_fileMenuSize == -1) {
+        GetFileMenu();
+    }
+    return m_fileMenuSize;
+}
+
+QByteArray const &LocalGitRepository::GetFileMenu() const {
+    if (m_fileMenu.toStdString() == "{}") {
+        QFile f(QDir::cleanPath(QString(baseDir) + m_localRepository + QDir::separator()
+                                + "etc/psa_webinterface/menu_config.json"));
+        if (f.exists()) {
+            if (f.open(QIODevice::ReadOnly | QIODevice::Text)) {
+                m_fileMenu = QTextStream(&f).readAll().toUtf8();
+
+                if (m_fileMenu.isValidUtf8()) {
+                    QString const &s = QString::fromUtf8(m_fileMenu);
+                    m_fileMenuSize = s.toLocal8Bit().size();
+                }
+            }
+        }
+    }
+    return m_fileMenu;
+}
+
+QByteArray LocalGitRepository::GetFileName(QString const &fId) {
+    QRegularExpressionMatch match;
+    static const QRegularExpression re("(master|[0-9]+)");
+    if (fId.lastIndexOf(re, -1, &match) != -1) {
+        int idx = fId.indexOf("/");
+        if (idx != -1) {
+            QString path = fId.mid(idx);
+            idx = path.indexOf(":");
+            if (idx != -1) {
+                path = path.mid(0, idx);
+                QString s = match.captured(match.lastCapturedIndex());
+                if (s != "master") {
+                    if (fId.contains("psa_tariff")) {
+                        QString fn(QDir::cleanPath(
+                            QString(baseDir) + QDir::separator() +
+                            QString(m_localRepository) + QDir::separator()
+                            + path + QDir::separator()
+                            + QString("tariff%1.json").arg(s.toUInt(), 2, 10, QChar('0'))));
+                        return fn.toUtf8();
+                    }
+                }
+            }
+        }
+    }
+    return QByteArray();
+}
+
+QByteArray LocalGitRepository::GetFile(QString const &fId) {
+    QByteArray a = GetFileName(fId);
+    if (a.isValidUtf8()) {
+        QFile fn(a);
+        if (fn.exists()) {
+            if (fn.open(QIODevice::ReadOnly)) {
+                return fn.readAll();
+            }
+        }
+    }
+
+    return QByteArray("{}");
+}
+
+int32_t LocalGitRepository::GetFileSize(QString const &fId) {
+    QByteArray a = GetFileName(fId);
+    if (a.isValidUtf8()) {
+        QFile fn(a);
+        if (fn.exists()) {
+            return fn.size();
+        }
+    }
+    return -1;
+}
+
+bool LocalGitRepository::SetFile(QString const &fId, QByteArray const &json) {
+    QByteArray a = GetFileName(fId);
+    if (a.isValidUtf8()) {
+        QFile fn(a);
+        if (fn.exists()) {
+            if (fn.open(QIODevice::WriteOnly)) {
+                quint64 bytesWritten = 0;
+                qint64 bytesToWrite = a.size();
+                while (bytesToWrite > 0 &&
+                      (bytesWritten = fn.write(json.constData(), bytesToWrite)) != -1) {
+                    bytesToWrite -= bytesWritten;
+                }
+                return (bytesToWrite == 0);
+            }
+        }
+
+    }
+    return false;
+}
diff --git a/CalculatorCInterface/local_git_repository.h b/CalculatorCInterface/local_git_repository.h
new file mode 100644
index 0000000..4447637
--- /dev/null
+++ b/CalculatorCInterface/local_git_repository.h
@@ -0,0 +1,30 @@
+#ifndef LOCAL_GIT_REPOSITORY_H_INCLUDED
+#define LOCAL_GIT_REPOSITORY_H_INCLUDED
+
+#include <QByteArray>
+#include <QString>
+
+#include <QJsonDocument>
+#include <QJsonArray>
+#include <QJsonObject>
+
+class LocalGitRepository {
+    QString m_localRepository;
+    mutable QByteArray m_fileMenu;
+    mutable int32_t m_fileMenuSize;
+public:
+    LocalGitRepository(QString const &localRepository);
+
+    static char const constexpr *baseDir = "H:\\";
+    QString gitRepository() const { return m_localRepository; }
+
+    QByteArray const &GetFileMenu() const;
+    int32_t GetFileMenuSize() const;
+    QByteArray GetFileName(QString const &fileId);
+    int32_t GetFileSize(QString const &fileId);
+    QByteArray GetFile(QString const &fileId);
+
+    bool SetFile(QString const &fileId, QByteArray const &json);
+};
+
+#endif // LOCAL_GIT_REPOSITORY_H_INCLUDED