diff --git a/src/lib/repository.h b/src/lib/repository.h
--- a/src/lib/repository.h
+++ b/src/lib/repository.h
@@ -153,6 +153,13 @@
      */
     void reload();
 
+    /**
+     * Add a custom search path to the repo.
+     * This path will be searched in addition to the usual locations for
+     * syntax and theme definition files.
+     */
+    void addSearchPath(const QString &path);
+
 private:
     Q_DISABLE_COPY(Repository)
     friend class RepositoryPrivate;
diff --git a/src/lib/repository.cpp b/src/lib/repository.cpp
--- a/src/lib/repository.cpp
+++ b/src/lib/repository.cpp
@@ -138,6 +138,9 @@
 
     loadSyntaxFolder(repo, QStringLiteral(":/org.kde.syntax-highlighting/syntax"));
 
+    foreach (const auto &path, m_extraSearchPaths)
+        loadSyntaxFolder(repo, path + QStringLiteral("/syntax"));
+
     m_sortedDefs.reserve(m_defs.size());
     for (auto it = m_defs.constBegin(); it != m_defs.constEnd(); ++it)
         m_sortedDefs.push_back(it.value());
@@ -153,6 +156,9 @@
     foreach (const auto &dir, dirs)
         loadThemeFolder(dir);
     loadThemeFolder(QStringLiteral(":/org.kde.syntax-highlighting/themes"));
+
+    foreach (const auto &path, m_extraSearchPaths)
+        loadThemeFolder(path + QStringLiteral("/themes"));
 }
 
 void RepositoryPrivate::loadSyntaxFolder(Repository *repo, const QString &path)
@@ -266,3 +272,9 @@
 
     d->load(this);
 }
+
+void Repository::addSearchPath(const QString &path)
+{
+    d->m_extraSearchPaths.append(path);
+    reload();
+}
diff --git a/src/lib/repository_p.h b/src/lib/repository_p.h
--- a/src/lib/repository_p.h
+++ b/src/lib/repository_p.h
@@ -47,6 +47,8 @@
     quint16 foldingRegionId(const QString &defName, const QString &foldName);
     quint16 nextFormatId();
 
+    QVector<QString> m_extraSearchPaths;
+
     QHash<QString, Definition> m_defs;
     QVector<Definition> m_sortedDefs;