diff --git a/ALICE3/Core/FastTracker.cxx b/ALICE3/Core/FastTracker.cxx
index 41c6637d59b..e20eb4b4227 100644
--- a/ALICE3/Core/FastTracker.cxx
+++ b/ALICE3/Core/FastTracker.cxx
@@ -34,10 +34,11 @@ namespace o2
 namespace fastsim
 {
 
-std::map<std::string, std::map<std::string, std::string>> GeometryContainer::parseTEnvConfiguration(std::string filename, std::vector<std::string>& layers)
+std::map<std::string, std::map<std::string, std::string>> GeometryContainer::parseTEnvConfiguration(std::string& filename, std::vector<std::string>& layers)
 {
   std::map<std::string, std::map<std::string, std::string>> configMap;
   filename = gSystem->ExpandPathName(filename.c_str());
+  LOG(info) << "Parsing TEnv configuration file: " << filename;
   TEnv env(filename.c_str());
   THashList* table = env.GetTable();
   layers.clear();
@@ -95,6 +96,16 @@ std::map<std::string, std::string> GeometryContainer::GeometryEntry::getConfigur
   }
 }
 
+bool GeometryContainer::GeometryEntry::hasValue(const std::string& layerName, const std::string& key) const
+{
+  auto layerIt = mConfigurations.find(layerName);
+  if (layerIt != mConfigurations.end()) {
+    auto keyIt = layerIt->second.find(key);
+    return keyIt != layerIt->second.end();
+  }
+  return false;
+}
+
 std::string GeometryContainer::GeometryEntry::getValue(const std::string& layerName, const std::string& key, bool require) const
 {
   auto layer = getConfiguration(layerName);
@@ -109,6 +120,14 @@ std::string GeometryContainer::GeometryEntry::getValue(const std::string& layerN
   }
 }
 
+void GeometryContainer::GeometryEntry::replaceValue(const std::string& layerName, const std::string& key, const std::string& value)
+{
+  if (!hasValue(layerName, key)) { // check that the key exists
+    LOG(fatal) << "Key " << key << " does not exist in layer " << layerName << ". Cannot replace value.";
+  }
+  setValue(layerName, key, value);
+}
+
 // +-~-<*>-~-+-~-<*>-~-+-~-<*>-~-+-~-<*>-~-+-~-<*>-~-+-~-<*>-~-+-~-<*>-~-+-~-<*>-~-+
 
 DetLayer* FastTracker::AddLayer(TString name, float r, float z, float x0, float xrho, float resRPhi, float resZ, float eff, int type)
diff --git a/ALICE3/Core/FastTracker.h b/ALICE3/Core/FastTracker.h
index 8703269296e..f0f27e7c4c6 100644
--- a/ALICE3/Core/FastTracker.h
+++ b/ALICE3/Core/FastTracker.h
@@ -42,27 +42,35 @@ class GeometryContainer
    * @param layers Vector to store the order of the layers as they appear in the file
    * @return A map where each key is a layer name and the value is another map of key-value pairs for that layer
    */
-  static std::map<std::string, std::map<std::string, std::string>> parseTEnvConfiguration(std::string filename, std::vector<std::string>& layers);
+  static std::map<std::string, std::map<std::string, std::string>> parseTEnvConfiguration(std::string& filename, std::vector<std::string>& layers);
 
   // A container for the geometry info
   struct GeometryEntry {
     // Default constructor
     GeometryEntry() = default;
-    explicit GeometryEntry(std::string filename) : name(filename)
+    explicit GeometryEntry(std::string filename)
     {
-      mConfigurations = GeometryContainer::parseTEnvConfiguration(filename, layerNames);
+      mFileName = filename;
+      mConfigurations = GeometryContainer::parseTEnvConfiguration(mFileName, mLayerNames);
+      LOG(info) << "Loaded geometry configuration from file: " << filename << " with " << mLayerNames.size() << " layers.";
+      if (mLayerNames.empty()) {
+        LOG(warning) << "No layers found in geometry configuration file: " << filename;
+      }
     }
     std::map<std::string, std::map<std::string, std::string>> getConfigurations() const { return mConfigurations; }
     std::map<std::string, std::string> getConfiguration(const std::string& layerName) const;
-    std::vector<std::string> getLayerNames() const { return layerNames; }
+    std::vector<std::string> getLayerNames() const { return mLayerNames; }
+    bool hasValue(const std::string& layerName, const std::string& key) const;
     std::string getValue(const std::string& layerName, const std::string& key, bool require = true) const;
+    void setValue(const std::string& layerName, const std::string& key, const std::string& value) { mConfigurations[layerName][key] = value; }
+    void replaceValue(const std::string& layerName, const std::string& key, const std::string& value);
     float getFloatValue(const std::string& layerName, const std::string& key) const { return std::stof(getValue(layerName, key)); }
     int getIntValue(const std::string& layerName, const std::string& key) const { return std::stoi(getValue(layerName, key)); }
 
    private:
-    std::string name; // Filename of the geometry
-    std::map<std::string, std::map<std::string, std::string>> mConfigurations;
-    std::vector<std::string> layerNames; // Ordered names of the layers
+    std::string mFileName;                                                     // Filename of the geometry
+    std::map<std::string, std::map<std::string, std::string>> mConfigurations; // Layer configurations
+    std::vector<std::string> mLayerNames;                                      // Ordered names of the layers
   };
 
   // Add a geometry entry from a configuration file
@@ -79,6 +87,7 @@ class GeometryContainer
   std::map<std::string, std::string> getConfiguration(const int id, const std::string& layerName) const { return entries.at(id).getConfiguration(layerName); }
 
   // Get specific values
+  std::string getValue(const int id, const std::string& layerName, const std::string& key, bool require = true) const { return entries.at(id).getValue(layerName, key, require); }
   float getFloatValue(const int id, const std::string& layerName, const std::string& key) const { return entries.at(id).getFloatValue(layerName, key); }
 
  private: