diff --git a/include/search_renderer.h b/include/search_renderer.h
index 0190ee5f0..d26d571a9 100644
--- a/include/search_renderer.h
+++ b/include/search_renderer.h
@@ -46,7 +46,7 @@ class SearchRenderer
    * @param start The start offset used for the srs.
    * @param estimatedResultCount The estimatedResultCount of the whole search
    */
-  SearchRenderer(zim::SearchResultSet srs, NameMapper* mapper,
+  SearchRenderer(zim::SearchResultSet srs, const NameMapper* mapper,
                  unsigned int start, unsigned int estimatedResultCount);
 
   /**
@@ -58,7 +58,7 @@ class SearchRenderer
    * @param start The start offset used for the srs.
    * @param estimatedResultCount The estimatedResultCount of the whole search
    */
-  SearchRenderer(zim::SearchResultSet srs, NameMapper* mapper, Library* library,
+  SearchRenderer(zim::SearchResultSet srs, const NameMapper* mapper, Library* library,
                  unsigned int start, unsigned int estimatedResultCount);
 
   ~SearchRenderer();
@@ -106,7 +106,7 @@ class SearchRenderer
  protected:
   std::string beautifyInteger(const unsigned int number);
   zim::SearchResultSet m_srs;
-  NameMapper* mp_nameMapper;
+  const NameMapper* mp_nameMapper;
   Library* mp_library;
   std::string searchBookQuery;
   std::string searchPattern;
diff --git a/src/search_renderer.cpp b/src/search_renderer.cpp
index c47b93368..ab49a8c8c 100644
--- a/src/search_renderer.cpp
+++ b/src/search_renderer.cpp
@@ -36,12 +36,12 @@ namespace kiwix
 {
 
 /* Constructor */
-SearchRenderer::SearchRenderer(zim::SearchResultSet srs, NameMapper* mapper,
+SearchRenderer::SearchRenderer(zim::SearchResultSet srs, const NameMapper* mapper,
                       unsigned int start, unsigned int estimatedResultCount)
     : SearchRenderer(srs, mapper, nullptr, start, estimatedResultCount)
 {}
 
-SearchRenderer::SearchRenderer(zim::SearchResultSet srs, NameMapper* mapper, Library* library,
+SearchRenderer::SearchRenderer(zim::SearchResultSet srs, const NameMapper* mapper, Library* library,
                       unsigned int start, unsigned int estimatedResultCount)
     : m_srs(srs),
       mp_nameMapper(mapper),