diff --git a/CMakeLists.txt b/CMakeLists.txt
index fec764c5b..8f2b21ed2 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -32,6 +32,9 @@ endif(enable-openmp)
 
 # enable mgis-function
 option(enable-mgis-function "enable mgis function" ON)
+option(enable-mgis-function-precompiled-operations
+       "enable compilations of some tensorial operations of basic functions. \
+        This requires mgis-functions to be handled **and** TFEL support" ON)
 # enable exceptions usage
 option(enable-exceptions "use exceptions to report contract violation and error reporting" OFF)
 
diff --git a/INSTALL-cmake.md b/INSTALL-cmake.md
index 189b1e04d..d411c6d4b 100644
--- a/INSTALL-cmake.md
+++ b/INSTALL-cmake.md
@@ -60,6 +60,9 @@ Options
   this behaviour.
 - `enable-mgis-function`: enable or disable compilation of the `MGIS/Function` library.
   By default, compilation of `MGIS/Function` is enabled.
+- `enable-mgis-function-precompiled-operations`: enable or disable compilation of
+   some operations on basic functions. This options is only meaningful if `MGIS/Function`
+   is enabled and if `TFEL` libraries are available.
 - `enable-exceptions`: use exceptions to report contract violation and error reporting.
    By default, contract violation leads to abort the program.
 - `enable-parallel-stl-algorithms`: by default, STL algorithms are used if available
diff --git a/bindings/python/src/CMakeLists.txt b/bindings/python/src/CMakeLists.txt
index 223af232c..a1ab67496 100644
--- a/bindings/python/src/CMakeLists.txt
+++ b/bindings/python/src/CMakeLists.txt
@@ -63,4 +63,8 @@ mgis_python_module(mgis_model model
  model-module.cxx
  Model.cxx)
 
-
+if(enable-mgis-function)
+  mgis_python_module(mgis_function function
+    function-module.cxx
+    Function.cxx)
+endif(enable-mgis-function)
diff --git a/bindings/python/src/Function.cxx b/bindings/python/src/Function.cxx
new file mode 100644
index 000000000..a69b33384
--- /dev/null
+++ b/bindings/python/src/Function.cxx
@@ -0,0 +1,72 @@
+/*!
+ * \file   bindings/python/src/Function.cxx
+ * \brief
+ * \author Thomas Helfer
+ * \date   18/11/2025
+ */
+
+#include <pybind11/pybind11.h>
+#include <pybind11/stl.h>
+#include "MGIS/Python/NumPySupport.hxx"
+#include "MGIS/Function/Function.hxx"
+#include "MGIS/Function/BasicLinearSpace.hxx"
+
+mgis::function::FunctionView<mgis::function::BasicLinearSpace,
+                             mgis::function::FunctionDataLayoutDescription{},
+                             false>
+mgis_convert_to_span(const pybind11::array_t<double> &o) {
+  using namespace mgis::function;
+  const auto i = o.request();
+  if (i.ndim != 1) {
+    const auto s = static_cast<mgis::size_type>(i.size);
+    const auto values = std::span{static_cast<const double *>(i.ptr), s};
+    return FunctionView<BasicLinearSpace, FunctionDataLayoutDescription{},
+                        false>{BasicLinearSpace{s}, values, 1};
+  }
+  mgis::raise("convert_to_span: expected one dimensional array");
+}  // end of mgis_convert_to_span
+
+void declareFunction(pybind11::module_ &m) {
+  // FunctionView<BasicLinearSpace, FunctionDataLayoutDescription{}, false
+  using mgis::real;
+  //
+  using BasicFunction =
+      mgis::function::Function<mgis::function::BasicLinearSpace>;
+  //
+  using BasicFunctionView = mgis::function::FunctionView<
+      mgis::function::BasicLinearSpace,
+      mgis::function::FunctionDataLayoutDescription{}, true>;
+
+  pybind11::class_<BasicFunction>(m, "BasicFunction",
+                                  pybind11::buffer_protocol())
+      .def_buffer([](BasicFunction &f) -> pybind11::buffer_info {
+        if (f.getNumberOfComponents() == 1) {
+          return pybind11::buffer_info(
+              f.data().data(), sizeof(real),
+              pybind11::format_descriptor<real>::format(), 1,
+              {getSpaceSize(f.getSpace())}, {sizeof(real)});
+        }
+        return pybind11::buffer_info(
+            f.data().data(), sizeof(real),
+            pybind11::format_descriptor<real>::format(), 2,
+            {getSpaceSize(f.getSpace()), f.getNumberOfComponents()},
+            {sizeof(real) * f.getNumberOfComponents(), sizeof(real)});
+      });
+
+  pybind11::class_<BasicFunctionView>(m, "BasicFunctionView",
+                                      pybind11::buffer_protocol())
+      .def_buffer([](BasicFunctionView &f) -> pybind11::buffer_info {
+        if (f.getNumberOfComponents() == 1) {
+          return pybind11::buffer_info(
+              f.data().data(), sizeof(real),
+              pybind11::format_descriptor<real>::format(), 1,
+              {getSpaceSize(f.getSpace())}, {sizeof(real) * f.getDataStride()});
+        }
+        return pybind11::buffer_info(
+            f.data().data(), sizeof(real),
+            pybind11::format_descriptor<real>::format(), 2,
+            {getSpaceSize(f.getSpace()), f.getNumberOfComponents()},
+            {sizeof(real) * f.getDataStride(), sizeof(real)});
+      });
+
+}  // end of declareFunction
diff --git a/bindings/python/src/function-module.cxx b/bindings/python/src/function-module.cxx
new file mode 100644
index 000000000..ba31f1440
--- /dev/null
+++ b/bindings/python/src/function-module.cxx
@@ -0,0 +1,20 @@
+/*!
+ * \file   bindings/python/src/function-module.cxx
+ * \brief
+ * \author Thomas Helfer
+ * \date   18/11/2025
+ * \copyright (C) Copyright Thomas Helfer 2018.
+ * Use, modification and distribution are subject
+ * to one of the following licences:
+ * - GNU Lesser General Public License (LGPL), Version 3.0. (See accompanying
+ *   file LGPL-3.0.txt)
+ * - CECILL-C,  Version 1.0 (See accompanying files
+ *   CeCILL-C_V1-en.txt and CeCILL-C_V1-fr.txt).
+ */
+
+#include <pybind11/pybind11.h>
+
+// forward declarations
+void declareFunction(pybind11::module_&);
+
+PYBIND11_MODULE(function, m) { declareFunction(m); }  // end of module function
diff --git a/docs/web/install.md b/docs/web/install.md
index 72833cb3d..09136ee6d 100644
--- a/docs/web/install.md
+++ b/docs/web/install.md
@@ -55,6 +55,17 @@ The simplest way to compile this package is:
 
 ## Options
 
+- `disable-tfel`: by default, `MGIS` tries to add support for `TFEL`,
+  notably if `tfel-config` is found in the `PATH`. This option disables
+  this behaviour.
+- `enable-mgis-function`: enable or disable compilation of the `MGIS/Function` library.
+  By default, compilation of `MGIS/Function` is enabled.
+- `enable-mgis-function-precompiled-operations`: enable or disable compilation of
+   some operations on basic functions. This options is only meaningful if `MGIS/Function`
+   is enabled and if `TFEL` libraries are available.
+- `enable-exceptions`: use exceptions to report contract violation and error reporting.
+   By default, contract violation leads to abort the program.
+- `enable-parallel-stl-algorithms`: by default, STL algorithms are used if available
 - `enable-c-bindings`: compiles the `C` bindings (default=OFF)
 - `enable-fortran-bindings`: compiles bindings for the `Fortran2003`
   language (default=OFF)
diff --git a/include/CMakeLists.txt b/include/CMakeLists.txt
index 539424fa0..0cecc999b 100644
--- a/include/CMakeLists.txt
+++ b/include/CMakeLists.txt
@@ -45,6 +45,7 @@ mgis_header(MGIS/Behaviour BehaviourIntegrationFailureAnalyser.hxx)
 mgis_header(MGIS/Behaviour FiniteStrainSupport.hxx)
 mgis_header(MGIS/Model Model.hxx)
 
+
 if(MGIS_HAVE_TFEL)
   mgis_header(MGIS Database.hxx)
 endif(MGIS_HAVE_TFEL)
@@ -87,25 +88,31 @@ if(enable-mgis-function)
   mgis_header(MGIS/Function Algorithms.hxx)
   mgis_header(MGIS/Function Algorithms.ixx)
   mgis_header(MGIS/Function Buffer.hxx)
-  mgis_header(MGIS/Function Tensors.hxx)
-  mgis_header(MGIS/Function Tensors.ixx)
-  mgis_header(MGIS/Function/Tensors TensorConcept.hxx)
-  mgis_header(MGIS/Function/Tensors TensorView.hxx)
-  mgis_header(MGIS/Function/Tensors TensorView.ixx)
-  mgis_header(MGIS/Function/Tensors TensorModifier.hxx)
-  mgis_header(MGIS/Function/Tensors TensorModifier.ixx)
-  mgis_header(MGIS/Function Mechanics.hxx)
-  mgis_header(MGIS/Function Mechanics.ixx)
   mgis_header(MGIS/Function CoalescedMemoryAccessFunctionViewBase.hxx)
   mgis_header(MGIS/Function CoalescedMemoryAccessFunctionViewBase.ixx)
-  mgis_header(MGIS/Function/Tensors CoalescedMemoryAccessTensorView.hxx)
-  mgis_header(MGIS/Function/Tensors CoalescedMemoryAccessTensorView.ixx)
-  mgis_header(MGIS/Function/Tensors CoalescedMemoryAccessCompositeTensorsView.hxx)
-  mgis_header(MGIS/Function/Tensors CoalescedMemoryAccessCompositeTensorsView.ixx)
   mgis_header(MGIS/Function StridedCoalescedMemoryAccessFunctionViewBase.hxx)
   mgis_header(MGIS/Function StridedCoalescedMemoryAccessFunctionViewBase.ixx)
-  mgis_header(MGIS/Function/Tensors StridedCoalescedMemoryAccessTensorView.hxx)
-  mgis_header(MGIS/Function/Tensors StridedCoalescedMemoryAccessTensorView.ixx)
-  mgis_header(MGIS/Function/Tensors StridedCoalescedMemoryAccessCompositeTensorsView.hxx)
-  mgis_header(MGIS/Function/Tensors StridedCoalescedMemoryAccessCompositeTensorsView.ixx)
+  if(MGIS_HAVE_TFEL)
+    mgis_header(MGIS/Function/TFEL TensorConcept.hxx)
+    mgis_header(MGIS/Function/TFEL Tensors.hxx)
+    mgis_header(MGIS/Function/TFEL Tensors.ixx)
+    mgis_header(MGIS/Function/TFEL TensorView.hxx)
+    mgis_header(MGIS/Function/TFEL TensorView.ixx)
+    mgis_header(MGIS/Function/TFEL CoalescedMemoryAccessTensorView.hxx)
+    mgis_header(MGIS/Function/TFEL CoalescedMemoryAccessTensorView.ixx)
+    mgis_header(MGIS/Function/TFEL CoalescedMemoryAccessCompositeTensorsView.hxx)
+    mgis_header(MGIS/Function/TFEL CoalescedMemoryAccessCompositeTensorsView.ixx)
+    mgis_header(MGIS/Function/TFEL StridedCoalescedMemoryAccessTensorView.hxx)
+    mgis_header(MGIS/Function/TFEL StridedCoalescedMemoryAccessTensorView.ixx)
+    mgis_header(MGIS/Function/TFEL StridedCoalescedMemoryAccessCompositeTensorsView.hxx)
+    mgis_header(MGIS/Function/TFEL StridedCoalescedMemoryAccessCompositeTensorsView.ixx)
+    mgis_header(MGIS/Function/TFEL TensorModifier.hxx)
+    mgis_header(MGIS/Function/TFEL TensorModifier.ixx)
+    mgis_header(MGIS/Function/TFEL Mechanics.hxx)
+    mgis_header(MGIS/Function/TFEL Mechanics.ixx)
+    if(enable-mgis-function-precompiled-operations)
+      mgis_header(MGIS/Function/TFEL TensorOperations.hxx)
+      mgis_header(MGIS/Function/TFEL MechanicalOperations.hxx)
+    endif(enable-mgis-function-precompiled-operations)
+  endif(MGIS_HAVE_TFEL)
 endif(enable-mgis-function)
diff --git a/include/MGIS/Function/Function.hxx b/include/MGIS/Function/Function.hxx
index a0c60fbb8..f3c686b22 100644
--- a/include/MGIS/Function/Function.hxx
+++ b/include/MGIS/Function/Function.hxx
@@ -530,6 +530,8 @@ namespace mgis::function {
      */
     [[nodiscard]] constexpr bool checkCompatibility(const FunctionView&) const;
     //! \return a view to the function values
+    [[nodiscard]] constexpr std::span<real> data() requires(is_mutable);
+    //! \return a view to the function values
     [[nodiscard]] constexpr std::span<const real> data() const;
     //! \brief destructor
     constexpr ~FunctionView() = default;
@@ -685,8 +687,6 @@ namespace mgis::function {
     view() const;
     //
     using FunctionView<Space, simple_data_layout_description<N>, true>::data;
-    //! \return a view to the function values
-    [[nodiscard]] constexpr std::span<real> data();
     /*!
      * \brief fill the structure using raw data
      *
diff --git a/include/MGIS/Function/Function.ixx b/include/MGIS/Function/Function.ixx
index 9d46b4db3..ce9e53b52 100644
--- a/include/MGIS/Function/Function.ixx
+++ b/include/MGIS/Function/Function.ixx
@@ -573,7 +573,14 @@ namespace mgis::function {
   template <LinearFunctionalSpaceConcept Space,
             FunctionDataLayoutDescription layout,
             bool is_mutable>
+  constexpr std::span<real>
+  FunctionView<Space, layout, is_mutable>::data() requires(is_mutable) {
+    return this->values;
+  }
 
+  template <LinearFunctionalSpaceConcept Space,
+            FunctionDataLayoutDescription layout,
+            bool is_mutable>
   constexpr std::span<const real>  //
   FunctionView<Space, layout, is_mutable>::data() const {
     return this->values;
@@ -711,11 +718,6 @@ namespace mgis::function {
     }
   }  // end of view
 
-  template <LinearFunctionalSpaceConcept Space, size_type N>
-  requires(N > 0) constexpr std::span<real> Function<Space, N>::data() {
-    return this->values;
-  }  // end of data
-
   template <LinearFunctionalSpaceConcept Space, size_type N>
   requires(N > 0) constexpr bool Function<Space, N>::fill(
       AbstractErrorHandler& eh, std::span<const real> values) noexcept {
diff --git a/include/MGIS/Function/Tensors/CoalescedMemoryAccessCompositeTensorsView.hxx b/include/MGIS/Function/TFEL/CoalescedMemoryAccessCompositeTensorsView.hxx
similarity index 90%
rename from include/MGIS/Function/Tensors/CoalescedMemoryAccessCompositeTensorsView.hxx
rename to include/MGIS/Function/TFEL/CoalescedMemoryAccessCompositeTensorsView.hxx
index 9f8ceaa6e..09ebb7223 100644
--- a/include/MGIS/Function/Tensors/CoalescedMemoryAccessCompositeTensorsView.hxx
+++ b/include/MGIS/Function/TFEL/CoalescedMemoryAccessCompositeTensorsView.hxx
@@ -1,5 +1,5 @@
 /*!
- * \file   MGIS/Function/Tensors/CoalescedMemoryAccessCompositeTensorsView.hxx
+ * \file   MGIS/Function/TFEL/CoalescedMemoryAccessCompositeTensorsView.hxx
  * \brief
  * \author Thomas Helfer
  * \date   27/10/2025
@@ -16,15 +16,15 @@
 #error "TFEL is required to use coalesced memory access tensor views"
 #endif /* MGIS_HAVE_TFEL */
 
-#ifndef LIB_MGIS_FUNCTION_TENSORS_COALESCEDMEMORYACCESSCOMPOSITETENSORSVIEW_HXX
-#define LIB_MGIS_FUNCTION_TENSORS_COALESCEDMEMORYACCESSCOMPOSITETENSORSVIEW_HXX
+#ifndef LIB_MGIS_FUNCTION_TFEL_COALESCEDMEMORYACCESSCOMPOSITETENSORVIEW_HXX
+#define LIB_MGIS_FUNCTION_TFEL_COALESCEDMEMORYACCESSCOMPOSITETENSORVIEW_HXX
 
 #include <tuple>
 #include <concepts>
 #include <type_traits>
 #include "TFEL/Math/Array/CoalescedView.hxx"
 #include "MGIS/Function/CoalescedMemoryAccessFunctionViewBase.hxx"
-#include "MGIS/Function/Tensors/TensorConcept.hxx"
+#include "MGIS/Function/TFEL/TensorConcept.hxx"
 
 namespace mgis::function {
 
@@ -115,7 +115,7 @@ namespace mgis::function {
 
 }  // namespace mgis::function
 
-#include "MGIS/Function/Tensors/CoalescedMemoryAccessCompositeTensorsView.ixx"
+#include "MGIS/Function/TFEL/CoalescedMemoryAccessCompositeTensorsView.ixx"
 
-#endif /* LIB_MGIS_FUNCTION_TENSORS_COALESCEDMEMORYACCESSCOMPOSITETENSORSVIEW_HXX \
+#endif /* LIB_MGIS_FUNCTION_TFEL_COALESCEDMEMORYACCESSCOMPOSITETENSORVIEW_HXX \
         */
diff --git a/include/MGIS/Function/Tensors/CoalescedMemoryAccessCompositeTensorsView.ixx b/include/MGIS/Function/TFEL/CoalescedMemoryAccessCompositeTensorsView.ixx
similarity index 93%
rename from include/MGIS/Function/Tensors/CoalescedMemoryAccessCompositeTensorsView.ixx
rename to include/MGIS/Function/TFEL/CoalescedMemoryAccessCompositeTensorsView.ixx
index a861f5cf8..36063fefc 100644
--- a/include/MGIS/Function/Tensors/CoalescedMemoryAccessCompositeTensorsView.ixx
+++ b/include/MGIS/Function/TFEL/CoalescedMemoryAccessCompositeTensorsView.ixx
@@ -1,5 +1,5 @@
 /*!
- * \file   MGIS/Function/Tensors/CoalescedMemoryAccessCompositeTensorsView.ixx
+ * \file   MGIS/Function/TFEL/CoalescedMemoryAccessCompositeTensorsView.ixx
  * \brief
  * \author Thomas Helfer
  * \date   27/10/2025
@@ -12,8 +12,8 @@
  *   CeCILL-C_V1-en.txt and CeCILL-C_V1-fr.txt).
  */
 
-#ifndef LIB_MGIS_FUNCTION_TENSORS_COALESCEDMEMORYACCESSCOMPOSITETENSORSVIEW_IXX
-#define LIB_MGIS_FUNCTION_TENSORS_COALESCEDMEMORYACCESSCOMPOSITETENSORSVIEW_IXX
+#ifndef LIB_MGIS_FUNCTION_TFEL_COALESCEDMEMORYACCESSCOMPOSITETENSORVIEW_IXX
+#define LIB_MGIS_FUNCTION_TFEL_COALESCEDMEMORYACCESSCOMPOSITETENSORVIEW_IXX
 
 namespace mgis::function {
 
@@ -105,5 +105,5 @@ namespace mgis::function {
 
 }  // namespace mgis::function
 
-#endif /* LIB_MGIS_FUNCTION_TENSORS_COALESCEDMEMORYACCESSCOMPOSITETENSORSVIEW_IXX \
+#endif /* LIB_MGIS_FUNCTION_TFEL_COALESCEDMEMORYACCESSCOMPOSITETENSORVIEW_IXX \
         */
diff --git a/include/MGIS/Function/Tensors/CoalescedMemoryAccessTensorView.hxx b/include/MGIS/Function/TFEL/CoalescedMemoryAccessTensorView.hxx
similarity index 88%
rename from include/MGIS/Function/Tensors/CoalescedMemoryAccessTensorView.hxx
rename to include/MGIS/Function/TFEL/CoalescedMemoryAccessTensorView.hxx
index 366886563..9e25ddb2b 100644
--- a/include/MGIS/Function/Tensors/CoalescedMemoryAccessTensorView.hxx
+++ b/include/MGIS/Function/TFEL/CoalescedMemoryAccessTensorView.hxx
@@ -1,5 +1,5 @@
 /*!
- * \file   MGIS/Function/Tensors/CoalescedMemoryAccessTensorView.hxx
+ * \file   MGIS/Function/TFEL/CoalescedMemoryAccessTensorView.hxx
  * \brief
  * \author Thomas Helfer
  * \date   27/10/2025
@@ -16,12 +16,12 @@
 #error "TFEL is required to use coalesced memory access tensor views"
 #endif /* MGIS_HAVE_TFEL */
 
-#ifndef LIB_MGIS_FUNCTION_TENSORS_COALESCEDMEMORYACCESSTENSORVIEW_HXX
-#define LIB_MGIS_FUNCTION_TENSORS_COALESCEDMEMORYACCESSTENSORVIEW_HXX
+#ifndef LIB_MGIS_FUNCTION_TFEL_COALESCEDMEMORYACCESSTENSORVIEW_HXX
+#define LIB_MGIS_FUNCTION_TFEL_COALESCEDMEMORYACCESSTENSORVIEW_HXX
 
 #include "TFEL/Math/Array/CoalescedView.hxx"
 #include "MGIS/Function/CoalescedMemoryAccessFunctionViewBase.hxx"
-#include "MGIS/Function/Tensors/TensorConcept.hxx"
+#include "MGIS/Function/TFEL/TensorConcept.hxx"
 
 namespace mgis::function {
 
@@ -87,6 +87,6 @@ namespace mgis::function {
 
 }  // namespace mgis::function
 
-#include "MGIS/Function/Tensors/CoalescedMemoryAccessTensorView.ixx"
+#include "MGIS/Function/TFEL/CoalescedMemoryAccessTensorView.ixx"
 
-#endif /* LIB_MGIS_FUNCTION_TENSORS_COALESCEDMEMORYACCESSTENSORVIEW_HXX */
+#endif /* LIB_MGIS_FUNCTION_TFEL_COALESCEDMEMORYACCESSTENSORVIEW_HXX */
diff --git a/include/MGIS/Function/Tensors/CoalescedMemoryAccessTensorView.ixx b/include/MGIS/Function/TFEL/CoalescedMemoryAccessTensorView.ixx
similarity index 91%
rename from include/MGIS/Function/Tensors/CoalescedMemoryAccessTensorView.ixx
rename to include/MGIS/Function/TFEL/CoalescedMemoryAccessTensorView.ixx
index b89c9e249..45b90a28f 100644
--- a/include/MGIS/Function/Tensors/CoalescedMemoryAccessTensorView.ixx
+++ b/include/MGIS/Function/TFEL/CoalescedMemoryAccessTensorView.ixx
@@ -1,5 +1,5 @@
 /*!
- * \file   MGIS/Function/Tensors/CoalescedMemoryAccessTensorView.ixx
+ * \file   MGIS/Function/TFEL/CoalescedMemoryAccessTensorView.ixx
  * \brief
  * \author Thomas Helfer
  * \date   27/10/2025
@@ -12,8 +12,8 @@
  *   CeCILL-C_V1-en.txt and CeCILL-C_V1-fr.txt).
  */
 
-#ifndef LIB_MGIS_FUNCTION_TENSORS_COALESCEDMEMORYACCESSTENSORVIEW_IXX
-#define LIB_MGIS_FUNCTION_TENSORS_COALESCEDMEMORYACCESSTENSORVIEW_IXX
+#ifndef LIB_MGIS_FUNCTION_TFEL_COALESCEDMEMORYACCESSTENSORVIEW_IXX
+#define LIB_MGIS_FUNCTION_TFEL_COALESCEDMEMORYACCESSTENSORVIEW_IXX
 
 namespace mgis::function {
 
@@ -74,4 +74,4 @@ namespace mgis::function {
 
 }  // namespace mgis::function
 
-#endif /* LIB_MGIS_FUNCTION_TENSORS_COALESCEDMEMORYACCESSTENSORVIEW_IXX */
+#endif /* LIB_MGIS_FUNCTION_TFEL_COALESCEDMEMORYACCESSTENSORVIEW_IXX */
diff --git a/include/MGIS/Function/TFEL/MechanicalOperations.hxx b/include/MGIS/Function/TFEL/MechanicalOperations.hxx
new file mode 100644
index 000000000..fb433bc05
--- /dev/null
+++ b/include/MGIS/Function/TFEL/MechanicalOperations.hxx
@@ -0,0 +1,71 @@
+/*!
+ * \file   MGIS/Function/TFEL/MechanicalOperations.hxx
+ * \brief
+ * \author Thomas Helfer
+ * \date   15/11/2025
+ * \copyright (C) Copyright Thomas Helfer 2018.
+ * Use, modification and distribution are subject
+ * to one of the following licences:
+ * - GNU Lesser General Public License (LGPL), Version 3.0. (See accompanying
+ *   file LGPL-3.0.txt)
+ * - CECILL-C,  Version 1.0 (See accompanying files
+ *   CeCILL-C_V1-en.txt and CeCILL-C_V1-fr.txt).
+ */
+
+#ifndef MGIS_HAVE_TFEL
+#error "TFEL is required to use tensor evaluators"
+#endif /* MGIS_HAVE_TFEL */
+
+#ifndef LIB_MGIS_FUNCTION_TFEL_MECHANICALOPERATIONS_HXX
+#define LIB_MGIS_FUNCTION_TFEL_MECHANICALOPERATIONS_HXX
+
+#include <optional>
+#include "MGIS/Config.hxx"
+#include "MGIS/Function/BasicLinearSpace.hxx"
+#include "MGIS/Function/Function.hxx"
+
+namespace mgis::function {
+
+  using BasicImmutableFunctionView =
+      FunctionView<BasicLinearSpace, FunctionDataLayoutDescription{}, false>;
+
+  MGIS_EXPORT std::optional<Function<BasicLinearSpace>> computeTrace(
+      Context&, const BasicImmutableFunctionView&) noexcept;
+
+  MGIS_EXPORT std::optional<Function<BasicLinearSpace>> computeVonMisesStress(
+      Context&, const BasicImmutableFunctionView&) noexcept;
+
+  MGIS_EXPORT std::optional<Function<BasicLinearSpace>>
+  computeHydrostraticPressure(Context&,
+                              const BasicImmutableFunctionView&) noexcept;
+
+  MGIS_EXPORT std::optional<Function<BasicLinearSpace>> computeEigenValues(
+      Context&, const BasicImmutableFunctionView&) noexcept;
+
+  MGIS_EXPORT std::optional<Function<BasicLinearSpace>>
+  computeCauchyStressFromFirstPiolaKirchhoffStress(
+      Context&,
+      const BasicImmutableFunctionView&,
+      const BasicImmutableFunctionView&) noexcept;
+
+  MGIS_EXPORT std::optional<Function<BasicLinearSpace>>
+  computeCauchyStressHydrostraticPressureFromFirstPiolaKirchhoffStress(
+      Context&,
+      const BasicImmutableFunctionView&,
+      const BasicImmutableFunctionView&) noexcept;
+
+  MGIS_EXPORT std::optional<Function<BasicLinearSpace>>
+  computeCauchyStressVonMisesStressFromFirstPiolaKirchhoffStress(
+      Context&,
+      const BasicImmutableFunctionView&,
+      const BasicImmutableFunctionView&) noexcept;
+
+  MGIS_EXPORT std::optional<Function<BasicLinearSpace>>
+  computeCauchyStressEigenValuesFromFirstPiolaKirchhoffStress(
+      Context&,
+      const BasicImmutableFunctionView&,
+      const BasicImmutableFunctionView&) noexcept;
+
+}  // namespace mgis::function
+
+#endif /* LIB_MGIS_FUNCTION_TFEL_MECHANICALOPERATIONS_HXX */
diff --git a/include/MGIS/Function/Mechanics.hxx b/include/MGIS/Function/TFEL/Mechanics.hxx
similarity index 88%
rename from include/MGIS/Function/Mechanics.hxx
rename to include/MGIS/Function/TFEL/Mechanics.hxx
index 389d1e9a0..36163648d 100644
--- a/include/MGIS/Function/Mechanics.hxx
+++ b/include/MGIS/Function/TFEL/Mechanics.hxx
@@ -1,5 +1,5 @@
 /*!
- * \file   MGIS/Function/Mechanics.hxx
+ * \file   MGIS/Function/TFEL/Mechanics.hxx
  * \brief
  * \author Thomas Helfer
  * \date   02/05/2025
@@ -12,18 +12,17 @@
  *   CeCILL-C_V1-en.txt and CeCILL-C_V1-fr.txt).
  */
 
-#ifndef LIB_MGIS_FUNCTION_MECHANICS_HXX
-#define LIB_MGIS_FUNCTION_MECHANICS_HXX
+#ifndef MGIS_HAVE_TFEL
+#error "TFEL is required to use this header"
+#endif /* MGIS_HAVE_TFEL */
+
+#ifndef LIB_MGIS_FUNCTION_TFEL_MECHANICS_HXX
+#define LIB_MGIS_FUNCTION_TFEL_MECHANICS_HXX
 
 #include <type_traits>
-#ifdef MGIS_HAVE_TFEL
 #include "TFEL/Material/FiniteStrainBehaviourTangentOperator.hxx"
-#endif /* MGIS_HAVE_TFEL */
-
 #include "MGIS/Function/Evaluator.hxx"
-#include "MGIS/Function/Tensors.hxx"
-
-#ifdef MGIS_HAVE_TFEL
+#include "MGIS/Function/TFEL/Tensors.hxx"
 
 namespace mgis::function {
 
@@ -68,8 +67,6 @@ namespace mgis::function {
 
 }  // end of namespace mgis::function
 
-#endif /* MGIS_HAVE_TFEL */
-
-#include "MGIS/Function/Mechanics.ixx"
+#include "MGIS/Function/TFEL/Mechanics.ixx"
 
 #endif /* LIB_MGIS_FUNCTION_MECHANICS_HXX */
diff --git a/include/MGIS/Function/Mechanics.ixx b/include/MGIS/Function/TFEL/Mechanics.ixx
similarity index 98%
rename from include/MGIS/Function/Mechanics.ixx
rename to include/MGIS/Function/TFEL/Mechanics.ixx
index b88627e19..112108a4d 100644
--- a/include/MGIS/Function/Mechanics.ixx
+++ b/include/MGIS/Function/TFEL/Mechanics.ixx
@@ -1,5 +1,5 @@
 /*!
- * \file   MGIS/Function/Mechanics.ixx
+ * \file   MGIS/Function/TFEL/Mechanics.ixx
  * \brief
  * \author Thomas Helfer
  * \date   02/05/2025
@@ -12,10 +12,8 @@
  *   CeCILL-C_V1-en.txt and CeCILL-C_V1-fr.txt).
  */
 
-#ifndef LIB_MGIS_FUNCTION_MECHANICS_IXX
-#define LIB_MGIS_FUNCTION_MECHANICS_IXX
-
-#ifdef MGIS_HAVE_TFEL
+#ifndef LIB_MGIS_FUNCTION_TFEL_MECHANICS_IXX
+#define LIB_MGIS_FUNCTION_TFEL_MECHANICS_IXX
 
 namespace mgis::function::internals {
 
@@ -286,6 +284,4 @@ namespace mgis::function {
 
 }  // end of namespace mgis::function
 
-#endif /* MGIS_HAVE_TFEL */
-
-#endif /* LIB_MGIS_FUNCTION_MECHANICS_IXX */
+#endif /* LIB_MGIS_FUNCTION_TFEL_MECHANICS_IXX */
diff --git a/include/MGIS/Function/Tensors/StridedCoalescedMemoryAccessCompositeTensorsView.hxx b/include/MGIS/Function/TFEL/StridedCoalescedMemoryAccessCompositeTensorsView.hxx
similarity index 90%
rename from include/MGIS/Function/Tensors/StridedCoalescedMemoryAccessCompositeTensorsView.hxx
rename to include/MGIS/Function/TFEL/StridedCoalescedMemoryAccessCompositeTensorsView.hxx
index afaf7f8c5..7b4243572 100644
--- a/include/MGIS/Function/Tensors/StridedCoalescedMemoryAccessCompositeTensorsView.hxx
+++ b/include/MGIS/Function/TFEL/StridedCoalescedMemoryAccessCompositeTensorsView.hxx
@@ -1,6 +1,6 @@
 /*!
  * \file
- * MGIS/Function/Tensors/StridedCoalescedMemoryAccessCompositeTensorsView.hxx
+ * MGIS/Function/TFEL/StridedCoalescedMemoryAccessCompositeTensorsView.hxx
  * \brief
  * \author Thomas Helfer
  * \date   27/10/2025
@@ -17,15 +17,15 @@
 #error "TFEL is required to use strided coalesced memory access tensor views"
 #endif /* MGIS_HAVE_TFEL */
 
-#ifndef LIB_MGIS_FUNCTION_TENSORS_STRIDEDCOALESCEDMEMORYACCESSCOMPOSITETENSORSVIEW_HXX
-#define LIB_MGIS_FUNCTION_TENSORS_STRIDEDCOALESCEDMEMORYACCESSCOMPOSITETENSORSVIEW_HXX
+#ifndef LIB_MGIS_FUNCTION_TFEL_STRIDEDCOALESCEDMEMORYACCESSCOMPOSITETENSORVIEW_HXX
+#define LIB_MGIS_FUNCTION_TFEL_STRIDEDCOALESCEDMEMORYACCESSCOMPOSITETENSORVIEW_HXX
 
 #include <tuple>
 #include <concepts>
 #include <type_traits>
 #include "TFEL/Math/Array/StridedCoalescedView.hxx"
 #include "MGIS/Function/StridedCoalescedMemoryAccessFunctionViewBase.hxx"
-#include "MGIS/Function/Tensors/TensorConcept.hxx"
+#include "MGIS/Function/TFEL/TensorConcept.hxx"
 
 namespace mgis::function {
 
@@ -116,7 +116,7 @@ namespace mgis::function {
 
 }  // namespace mgis::function
 
-#include "MGIS/Function/Tensors/StridedCoalescedMemoryAccessCompositeTensorsView.ixx"
+#include "MGIS/Function/TFEL/StridedCoalescedMemoryAccessCompositeTensorsView.ixx"
 
-#endif /* LIB_MGIS_FUNCTION_TENSORS_STRIDEDCOALESCEDMEMORYACCESSCOMPOSITETENSORSVIEW_HXX \
+#endif /* LIB_MGIS_FUNCTION_TFEL_STRIDEDCOALESCEDMEMORYACCESSCOMPOSITETENSORVIEW_HXX \
         */
diff --git a/include/MGIS/Function/Tensors/StridedCoalescedMemoryAccessCompositeTensorsView.ixx b/include/MGIS/Function/TFEL/StridedCoalescedMemoryAccessCompositeTensorsView.ixx
similarity index 92%
rename from include/MGIS/Function/Tensors/StridedCoalescedMemoryAccessCompositeTensorsView.ixx
rename to include/MGIS/Function/TFEL/StridedCoalescedMemoryAccessCompositeTensorsView.ixx
index 0a1733fa5..67a2e409b 100644
--- a/include/MGIS/Function/Tensors/StridedCoalescedMemoryAccessCompositeTensorsView.ixx
+++ b/include/MGIS/Function/TFEL/StridedCoalescedMemoryAccessCompositeTensorsView.ixx
@@ -1,6 +1,6 @@
 /*!
  * \file
- * MGIS/Function/Tensors/StridedCoalescedMemoryAccessCompositeTensorsView.ixx
+ * MGIS/Function/TFEL/StridedCoalescedMemoryAccessCompositeTensorsView.ixx
  * \brief
  * \author Thomas Helfer
  * \date   27/10/2025
@@ -13,8 +13,8 @@
  *   CeCILL-C_V1-en.txt and CeCILL-C_V1-fr.txt).
  */
 
-#ifndef LIB_MGIS_FUNCTION_TENSORS_STRIDEDCOALESCEDMEMORYACCESSCOMPOSITETENSORSVIEW_IXX
-#define LIB_MGIS_FUNCTION_TENSORS_STRIDEDCOALESCEDMEMORYACCESSCOMPOSITETENSORSVIEW_IXX
+#ifndef LIB_MGIS_FUNCTION_TFEL_STRIDEDCOALESCEDMEMORYACCESSCOMPOSITETENSORSVIEW_IXX
+#define LIB_MGIS_FUNCTION_TFEL_STRIDEDCOALESCEDMEMORYACCESSCOMPOSITETENSORSVIEW_IXX
 
 namespace mgis::function {
 
@@ -108,5 +108,5 @@ namespace mgis::function {
 
 }  // namespace mgis::function
 
-#endif /* LIB_MGIS_FUNCTION_TENSORS_STRIDEDCOALESCEDMEMORYACCESSCOMPOSITETENSORSVIEW_IXX \
+#endif /* LIB_MGIS_FUNCTION_TFEL_STRIDEDCOALESCEDMEMORYACCESSCOMPOSITETENSORSVIEW_IXX \
         */
diff --git a/include/MGIS/Function/Tensors/StridedCoalescedMemoryAccessTensorView.hxx b/include/MGIS/Function/TFEL/StridedCoalescedMemoryAccessTensorView.hxx
similarity index 87%
rename from include/MGIS/Function/Tensors/StridedCoalescedMemoryAccessTensorView.hxx
rename to include/MGIS/Function/TFEL/StridedCoalescedMemoryAccessTensorView.hxx
index f420f2da1..0ce5849b1 100644
--- a/include/MGIS/Function/Tensors/StridedCoalescedMemoryAccessTensorView.hxx
+++ b/include/MGIS/Function/TFEL/StridedCoalescedMemoryAccessTensorView.hxx
@@ -1,5 +1,5 @@
 /*!
- * \file   MGIS/Function/Tensors/StridedCoalescedMemoryAccessTensorView.hxx
+ * \file   MGIS/Function/TFEL/StridedCoalescedMemoryAccessTensorView.hxx
  * \brief
  * \author Thomas Helfer
  * \date   27/10/2025
@@ -16,12 +16,12 @@
 #error "TFEL is required to use coalesced memory access tensor views"
 #endif /* MGIS_HAVE_TFEL */
 
-#ifndef LIB_MGIS_FUNCTION_TENSORS_STRIDEDCOALESCEDMEMORYACCESSTENSORVIEW_HXX
-#define LIB_MGIS_FUNCTION_TENSORS_STRIDEDCOALESCEDMEMORYACCESSTENSORVIEW_HXX
+#ifndef LIB_MGIS_FUNCTION_TFEL_STRIDEDCOALESCEDMEMORYACCESSTENSORVIEW_HXX
+#define LIB_MGIS_FUNCTION_TFEL_STRIDEDCOALESCEDMEMORYACCESSTENSORVIEW_HXX
 
 #include "TFEL/Math/Array/StridedCoalescedView.hxx"
 #include "MGIS/Function/StridedCoalescedMemoryAccessFunctionViewBase.hxx"
-#include "MGIS/Function/Tensors/TensorConcept.hxx"
+#include "MGIS/Function/TFEL/TensorConcept.hxx"
 
 namespace mgis::function {
 
@@ -83,7 +83,7 @@ namespace mgis::function {
 
 }  // namespace mgis::function
 
-#include "MGIS/Function/Tensors/StridedCoalescedMemoryAccessTensorView.ixx"
+#include "MGIS/Function/TFEL/StridedCoalescedMemoryAccessTensorView.ixx"
 
-#endif /* LIB_MGIS_FUNCTION_TENSORS_STRIDEDCOALESCEDMEMORYACCESSTENSORVIEW_HXX \
+#endif /* LIB_MGIS_FUNCTION_TFEL_STRIDEDCOALESCEDMEMORYACCESSTENSORVIEW_HXX \
         */
diff --git a/include/MGIS/Function/Tensors/StridedCoalescedMemoryAccessTensorView.ixx b/include/MGIS/Function/TFEL/StridedCoalescedMemoryAccessTensorView.ixx
similarity index 91%
rename from include/MGIS/Function/Tensors/StridedCoalescedMemoryAccessTensorView.ixx
rename to include/MGIS/Function/TFEL/StridedCoalescedMemoryAccessTensorView.ixx
index 7c233a41e..5db0503d3 100644
--- a/include/MGIS/Function/Tensors/StridedCoalescedMemoryAccessTensorView.ixx
+++ b/include/MGIS/Function/TFEL/StridedCoalescedMemoryAccessTensorView.ixx
@@ -1,5 +1,5 @@
 /*!
- * \file   MGIS/Function/Tensors/StridedCoalescedMemoryAccessTensorView.ixx
+ * \file   MGIS/Function/TFEL/StridedCoalescedMemoryAccessTensorView.ixx
  * \brief
  * \author Thomas Helfer
  * \date   17/01/2026
@@ -12,8 +12,8 @@
  *   CeCILL-C_V1-en.txt and CeCILL-C_V1-fr.txt).
  */
 
-#ifndef LIB_MGIS_FUNCTION_TENSORS_STRIDEDCOALESCEDMEMORYACCESSTENSORVIEW_IXX
-#define LIB_MGIS_FUNCTION_TENSORS_STRIDEDCOALESCEDMEMORYACCESSTENSORVIEW_IXX
+#ifndef LIB_MGIS_FUNCTION_TFEL_STRIDEDCOALESCEDMEMORYACCESSTENSORVIEW_IXX
+#define LIB_MGIS_FUNCTION_TFEL_STRIDEDCOALESCEDMEMORYACCESSTENSORVIEW_IXX
 
 namespace mgis::function {
 
@@ -82,5 +82,5 @@ namespace mgis::function {
 
 }  // namespace mgis::function
 
-#endif /* LIB_MGIS_FUNCTION_TENSORS_STRIDEDCOALESCEDMEMORYACCESSTENSORVIEW_IXX \
+#endif /* LIB_MGIS_FUNCTION_TFEL_STRIDEDCOALESCEDMEMORYACCESSTENSORVIEW_IXX \
         */
diff --git a/include/MGIS/Function/Tensors/TensorConcept.hxx b/include/MGIS/Function/TFEL/TensorConcept.hxx
similarity index 90%
rename from include/MGIS/Function/Tensors/TensorConcept.hxx
rename to include/MGIS/Function/TFEL/TensorConcept.hxx
index e1cc9a950..9a7dc6d01 100644
--- a/include/MGIS/Function/Tensors/TensorConcept.hxx
+++ b/include/MGIS/Function/TFEL/TensorConcept.hxx
@@ -1,16 +1,23 @@
 /*!
- * \file   MGIS/Function/Tensors/TensorConcept.hxx
+ * \file   MGIS/Function/TFEL/TensorConcept.hxx
  * \brief
  * \author Thomas Helfer
  * \date   10/05/2025
+ * \copyright (C) Copyright Thomas Helfer 2018.
+ * Use, modification and distribution are subject
+ * to one of the following licences:
+ * - GNU Lesser General Public License (LGPL), Version 3.0. (See accompanying
+ *   file LGPL-3.0.txt)
+ * - CECILL-C,  Version 1.0 (See accompanying files
+ *   CeCILL-C_V1-en.txt and CeCILL-C_V1-fr.txt).
  */
 
 #ifndef MGIS_HAVE_TFEL
 #error "TFEL is required to use tensor evaluators"
 #endif /* MGIS_HAVE_TFEL */
 
-#ifndef LIB_MGIS_FUNCTION_TENSORCONCEPT_HXX
-#define LIB_MGIS_FUNCTION_TENSORCONCEPT_HXX
+#ifndef LIB_MGIS_FUNCTION_TFEL_TENSORCONCEPT_HXX
+#define LIB_MGIS_FUNCTION_TFEL_TENSORCONCEPT_HXX
 
 #include <type_traits>
 #include "TFEL/Math/fsarray.hxx"
@@ -154,4 +161,4 @@ namespace mgis::function {
 
 }  // end of namespace mgis::function
 
-#endif /* LIB_MGIS_FUNCTION_TENSORCONCEPT_HXX */
+#endif /* LIB_MGIS_FUNCTION_TFEL_TENSORCONCEPT_HXX */
diff --git a/include/MGIS/Function/Tensors/TensorModifier.hxx b/include/MGIS/Function/TFEL/TensorModifier.hxx
similarity index 72%
rename from include/MGIS/Function/Tensors/TensorModifier.hxx
rename to include/MGIS/Function/TFEL/TensorModifier.hxx
index 6c0bd028a..2cf2bf249 100644
--- a/include/MGIS/Function/Tensors/TensorModifier.hxx
+++ b/include/MGIS/Function/TFEL/TensorModifier.hxx
@@ -1,16 +1,27 @@
 /*!
- * \file   MGIS/Function/Tensors/TensorModifier.hxx
+ * \file   MGIS/Function/TFEL/TensorModifier.hxx
  * \brief
  * \author Thomas Helfer
  * \date   13/05/2025
+ * \copyright (C) Copyright Thomas Helfer 2018.
+ * Use, modification and distribution are subject
+ * to one of the following licences:
+ * - GNU Lesser General Public License (LGPL), Version 3.0. (See accompanying
+ *   file LGPL-3.0.txt)
+ * - CECILL-C,  Version 1.0 (See accompanying files
+ *   CeCILL-C_V1-en.txt and CeCILL-C_V1-fr.txt).
  */
 
-#ifndef LIB_MGIS_FUNCTION_TENSORMODIFIER_HXX
-#define LIB_MGIS_FUNCTION_TENSORMODIFIER_HXX
+#ifndef MGIS_HAVE_TFEL
+#error "TFEL is required to use this header"
+#endif /* MGIS_HAVE_TFEL */
+
+#ifndef LIB_MGIS_FUNCTION_TFEL_TENSORMODIFIER_HXX
+#define LIB_MGIS_FUNCTION_TFEL_TENSORMODIFIER_HXX
 
 #include "MGIS/Function/Evaluator.hxx"
 #include "MGIS/Function/EvaluatorModifierBase.hxx"
-#include "MGIS/Function/Tensors/TensorConcept.hxx"
+#include "MGIS/Function/TFEL/TensorConcept.hxx"
 
 namespace mgis::function {
 
@@ -58,6 +69,6 @@ namespace mgis::function {
 
 }  // end of namespace mgis::function
 
-#include "MGIS/Function/Tensors/TensorModifier.ixx"
+#include "MGIS/Function/TFEL/TensorModifier.ixx"
 
-#endif /* LIB_MGIS_FUNCTION_TENSORMODIFIER_HXX */
+#endif /* LIB_MGIS_FUNCTION_TFEL_TENSORMODIFIER_HXX */
diff --git a/include/MGIS/Function/Tensors/TensorModifier.ixx b/include/MGIS/Function/TFEL/TensorModifier.ixx
similarity index 68%
rename from include/MGIS/Function/Tensors/TensorModifier.ixx
rename to include/MGIS/Function/TFEL/TensorModifier.ixx
index fedfb2865..1a5d376ab 100644
--- a/include/MGIS/Function/Tensors/TensorModifier.ixx
+++ b/include/MGIS/Function/TFEL/TensorModifier.ixx
@@ -1,12 +1,19 @@
 /*!
- * \file   MGIS/Function/TensorModifier.ixx
+ * \file   MGIS/Function/TFEL/TensorModifier.ixx
  * \brief
  * \author Thomas Helfer
  * \date   13/05/2025
+ * \copyright (C) Copyright Thomas Helfer 2018.
+ * Use, modification and distribution are subject
+ * to one of the following licences:
+ * - GNU Lesser General Public License (LGPL), Version 3.0. (See accompanying
+ *   file LGPL-3.0.txt)
+ * - CECILL-C,  Version 1.0 (See accompanying files
+ *   CeCILL-C_V1-en.txt and CeCILL-C_V1-fr.txt).
  */
 
-#ifndef LIB_MGIS_FUNCTION_TENSORMODIFIER_IXX
-#define LIB_MGIS_FUNCTION_TENSORMODIFIER_IXX
+#ifndef LIB_MGIS_FUNCTION_TFEL_TENSORMODIFIER_IXX
+#define LIB_MGIS_FUNCTION_TFEL_TENSORMODIFIER_IXX
 
 namespace mgis::function {
 
@@ -35,4 +42,4 @@ namespace mgis::function {
 
 }  // end of namespace mgis::function
 
-#endif /* LIB_MGIS_FUNCTION_TENSORMODIFIER_IXX */
+#endif /* LIB_MGIS_FUNCTION_TFEL_TENSORMODIFIER_IXX */
diff --git a/include/MGIS/Function/TFEL/TensorOperations.hxx b/include/MGIS/Function/TFEL/TensorOperations.hxx
new file mode 100644
index 000000000..e33b64a4e
--- /dev/null
+++ b/include/MGIS/Function/TFEL/TensorOperations.hxx
@@ -0,0 +1,106 @@
+/*!
+ * \file   MGIS/Function/TFEL/TensorOperations.hxx
+ * \brief
+ * \author Thomas Helfer
+ * \date   15/11/2025
+ * \copyright (C) Copyright Thomas Helfer 2018.
+ * Use, modification and distribution are subject
+ * to one of the following licences:
+ * - GNU Lesser General Public License (LGPL), Version 3.0. (See accompanying
+ *   file LGPL-3.0.txt)
+ * - CECILL-C,  Version 1.0 (See accompanying files
+ *   CeCILL-C_V1-en.txt and CeCILL-C_V1-fr.txt).
+ */
+
+#ifndef MGIS_HAVE_TFEL
+#error "TFEL is required to use tensor evaluators"
+#endif /* MGIS_HAVE_TFEL */
+
+#ifndef LIB_MGIS_FUNCTION_TFEL_TENSOROPERATIONS_HXX
+#define LIB_MGIS_FUNCTION_TFEL_TENSOROPERATIONS_HXX
+
+#include <span>
+#include <optional>
+#include "MGIS/Config.hxx"
+#include "MGIS/Function/BasicLinearSpace.hxx"
+#include "MGIS/Function/Function.hxx"
+
+namespace mgis::function {
+
+  /*!
+   * \brief a simple alias to shorten the declaration of the functions
+   */
+  using BasicImmutableFunctionView =
+      FunctionView<BasicLinearSpace, FunctionDataLayoutDescription{}, false>;
+
+  /*!
+   * \brief type of tensor that are supported
+   */
+  enum struct TensorType { STENSOR, TENSOR, ST2TOST2 };
+  /*!
+   * \brief supported rotation operations
+   *
+   * - If the rotation operation is `FORWARD`, the given rotation matrix is used
+   *   directly.
+   * - If the rotation operation is `BACKWARD`, the transposed of the rotation
+   *   matrix is used.
+   */
+  enum struct RotationOperation { FORWARD, BACKWARD };
+
+  MGIS_EXPORT std::optional<Function<BasicLinearSpace>> computeRotatedTensor(
+      Context&,
+      const BasicImmutableFunctionView&,
+      const BasicImmutableFunctionView&,
+      const TensorType = TensorType::STENSOR,
+      const RotationOperation = RotationOperation::FORWARD) noexcept;
+
+  MGIS_EXPORT std::optional<Function<BasicLinearSpace>> computeRotatedTensor(
+      Context&,
+      const BasicImmutableFunctionView&,
+      const std::span<real>&,
+      const TensorType = TensorType::STENSOR,
+      const RotationOperation = RotationOperation::FORWARD) noexcept;
+
+  MGIS_EXPORT std::optional<Function<BasicLinearSpace>>
+  computeRotatedSymmetricTensor(
+      Context&,
+      const BasicImmutableFunctionView&,
+      const BasicImmutableFunctionView&,
+      const RotationOperation = RotationOperation::FORWARD) noexcept;
+
+  MGIS_EXPORT std::optional<Function<BasicLinearSpace>>
+  computeRotatedSymmetricTensor(
+      Context&,
+      const BasicImmutableFunctionView&,
+      const std::span<real>&,
+      const RotationOperation = RotationOperation::FORWARD) noexcept;
+
+  MGIS_EXPORT std::optional<Function<BasicLinearSpace>>
+  computeRotatedUnsymmetricTensor(
+      Context&,
+      const BasicImmutableFunctionView&,
+      const BasicImmutableFunctionView&,
+      const RotationOperation = RotationOperation::FORWARD) noexcept;
+
+  MGIS_EXPORT std::optional<Function<BasicLinearSpace>>
+  computeRotatedUnsymmetricTensor(
+      Context&,
+      const BasicImmutableFunctionView&,
+      const std::span<real>&,
+      const RotationOperation = RotationOperation::FORWARD) noexcept;
+
+  MGIS_EXPORT std::optional<Function<BasicLinearSpace>> computeRotatedST2toST2(
+      Context&,
+      const BasicImmutableFunctionView&,
+      const BasicImmutableFunctionView&,
+      const RotationOperation = RotationOperation::FORWARD) noexcept;
+
+  MGIS_EXPORT std::optional<Function<BasicLinearSpace>> computeRotatedST2toST2(
+      Context&,
+      const BasicImmutableFunctionView&,
+      const std::span<real>&,
+      const RotationOperation = RotationOperation::FORWARD) noexcept;
+
+}  // namespace mgis::function
+
+#endif /* LIB_MGIS_FUNCTION_TFEL_TENSOROPERATIONS_HXX */
diff --git a/include/MGIS/Function/Tensors/TensorView.hxx b/include/MGIS/Function/TFEL/TensorView.hxx
similarity index 89%
rename from include/MGIS/Function/Tensors/TensorView.hxx
rename to include/MGIS/Function/TFEL/TensorView.hxx
index 08ed815b9..0e953a89f 100644
--- a/include/MGIS/Function/Tensors/TensorView.hxx
+++ b/include/MGIS/Function/TFEL/TensorView.hxx
@@ -1,19 +1,30 @@
 /*!
- * \file   MGIS/Function/TensorView.hxx
+ * \file   MGIS/Function/TFEL/TensorView.hxx
  * \brief  This file declares the TensorView class and the
  * transform function, as well as the as_fsarray, as_tvector,
  * as_tmatrix, as_stensor and as_tensor modifiers.
  * \author Thomas Helfer
  * \date   09/05/2025
+ * \copyright (C) Copyright Thomas Helfer 2018.
+ * Use, modification and distribution are subject
+ * to one of the following licences:
+ * - GNU Lesser General Public License (LGPL), Version 3.0. (See accompanying
+ *   file LGPL-3.0.txt)
+ * - CECILL-C,  Version 1.0 (See accompanying files
+ *   CeCILL-C_V1-en.txt and CeCILL-C_V1-fr.txt).
  */
 
-#ifndef LIB_MGIS_FUNCTION_TENSORVIEW_HXX
-#define LIB_MGIS_FUNCTION_TENSORVIEW_HXX
+#ifndef MGIS_HAVE_TFEL
+#error "TFEL is required to use this header"
+#endif /* MGIS_HAVE_TFEL */
+
+#ifndef LIB_MGIS_FUNCTION_TFEL_TENSORVIEW_HXX
+#define LIB_MGIS_FUNCTION_TFEL_TENSORVIEW_HXX
 
 #include <span>
 #include "MGIS/Contract.hxx"
 #include "MGIS/Function/Function.hxx"
-#include "MGIS/Function/Tensors/TensorConcept.hxx"
+#include "MGIS/Function/TFEL/TensorConcept.hxx"
 
 namespace mgis::function {
 
@@ -152,6 +163,6 @@ namespace mgis::function {
 
 }  // end of namespace mgis::function
 
-#include "MGIS/Function/Tensors/TensorView.ixx"
+#include "MGIS/Function/TFEL/TensorView.ixx"
 
-#endif /* LIB_MGIS_FUNCTION_TENSORVIEW_HXX */
+#endif /* LIB_MGIS_FUNCTION_TFEL_TENSORVIEW_HXX */
diff --git a/include/MGIS/Function/Tensors/TensorView.ixx b/include/MGIS/Function/TFEL/TensorView.ixx
similarity index 94%
rename from include/MGIS/Function/Tensors/TensorView.ixx
rename to include/MGIS/Function/TFEL/TensorView.ixx
index 795e1e833..29f1a0734 100644
--- a/include/MGIS/Function/Tensors/TensorView.ixx
+++ b/include/MGIS/Function/TFEL/TensorView.ixx
@@ -1,12 +1,20 @@
+
 /*!
- * \file   MGIS/Function/TensorView.ixx
+ * \file   MGIS/Function/TFEL/TensorView.ixx
  * \brief
  * \author Thomas Helfer
  * \date   10/05/2025
+ * \copyright (C) Copyright Thomas Helfer 2018.
+ * Use, modification and distribution are subject
+ * to one of the following licences:
+ * - GNU Lesser General Public License (LGPL), Version 3.0. (See accompanying
+ *   file LGPL-3.0.txt)
+ * - CECILL-C,  Version 1.0 (See accompanying files
+ *   CeCILL-C_V1-en.txt and CeCILL-C_V1-fr.txt).
  */
 
-#ifndef LIB_MGIS_FUNCTION_TENSORVIEW_IXX
-#define LIB_MGIS_FUNCTION_TENSORVIEW_IXX
+#ifndef LIB_MGIS_FUNCTION_TFEL_TENSORVIEW_IXX
+#define LIB_MGIS_FUNCTION_TFEL_TENSORVIEW_IXX
 
 #include <utility>
 
@@ -221,4 +229,4 @@ namespace mgis::function {
 
 }  // end of namespace mgis::function
 
-#endif /* LIB_MGIS_FUNCTION_TENSORVIEW_IXX */
+#endif /* LIB_MGIS_FUNCTION_TFEL_TENSORVIEW_IXX */
diff --git a/include/MGIS/Function/TensorialFunction.hxx b/include/MGIS/Function/TFEL/TensorialFunction.hxx
similarity index 93%
rename from include/MGIS/Function/TensorialFunction.hxx
rename to include/MGIS/Function/TFEL/TensorialFunction.hxx
index 578d6f7f6..1b6fccb95 100644
--- a/include/MGIS/Function/TensorialFunction.hxx
+++ b/include/MGIS/Function/TFEL/TensorialFunction.hxx
@@ -1,5 +1,5 @@
 /*!
- * \file   MGIS/Function/TensorialFunction.hxx
+ * \file   MGIS/Function/TFEL/TensorialFunction.hxx
  * \brief
  * \author Thomas Helfer
  * \date   28/08/2025
@@ -12,13 +12,15 @@
  *   CeCILL-C_V1-en.txt and CeCILL-C_V1-fr.txt).
  */
 
-#ifndef LIB_MGIS_FUNCTION_TENSORIALFUNCTION_HXX
-#define LIB_MGIS_FUNCTION_TENSORIALFUNCTION_HXX
+#ifndef MGIS_HAVE_TFEL
+#error "TFEL is required to use this header"
+#endif /* MGIS_HAVE_TFEL */
 
-#include "MGIS/Function/Function.hxx"
-#include "MGIS/Function/Tensors.hxx"
+#ifndef LIB_MGIS_FUNCTION_TFEL_TENSORIALFUNCTION_HXX
+#define LIB_MGIS_FUNCTION_TFEL_TENSORIALFUNCTION_HXX
 
-#ifdef MGIS_HAVE_TFEL
+#include "MGIS/Function/Function.hxx"
+#include "MGIS/Function/TFEL/Tensors.hxx"
 
 namespace mgis::function {
 
@@ -150,8 +152,6 @@ namespace mgis::function {
 
 }  // end of namespace mgis::function
 
-#endif /* MGIS_HAVE_TFEL */
-
-#include "MGIS/Function/TensorialFunction.ixx"
+#include "MGIS/Function/TFEL/TensorialFunction.ixx"
 
-#endif /* LIB_MGIS_FUNCTION_TENSORIALFUNCTION_HXX */
+#endif /* LIB_MGIS_FUNCTION_TFEL_TENSORIALFUNCTION_HXX */
diff --git a/include/MGIS/Function/TensorialFunction.ixx b/include/MGIS/Function/TFEL/TensorialFunction.ixx
similarity index 94%
rename from include/MGIS/Function/TensorialFunction.ixx
rename to include/MGIS/Function/TFEL/TensorialFunction.ixx
index b8c3b3e8c..e008dd73e 100644
--- a/include/MGIS/Function/TensorialFunction.ixx
+++ b/include/MGIS/Function/TFEL/TensorialFunction.ixx
@@ -1,5 +1,6 @@
+
 /*!
- * \file   MGIS/Function/TensorialFunction.ixx
+ * \file   MGIS/Function/TFEL/TensorialFunction.ixx
  * \brief
  * \author Thomas Helfer
  * \date   28/08/2025
@@ -12,10 +13,8 @@
  *   CeCILL-C_V1-en.txt and CeCILL-C_V1-fr.txt).
  */
 
-#ifndef LIB_MGIS_FUNCTION_TENSORIALFUNCTION_IXX
-#define LIB_MGIS_FUNCTION_TENSORIALFUNCTION_IXX
-
-#ifdef MGIS_HAVE_TFEL
+#ifndef LIB_MGIS_FUNCTION_TFEL_TENSORIALFUNCTION_IXX
+#define LIB_MGIS_FUNCTION_TFEL_TENSORIALFUNCTION_IXX
 
 namespace mgis::function {
 
@@ -105,6 +104,4 @@ namespace mgis::function {
 
 }  // end of namespace mgis::function
 
-#endif /* MGIS_HAVE_TFEL */
-
-#endif /* LIB_MGIS_FUNCTION_TENSORIALFUNCTION_HXX */
+#endif /* LIB_MGIS_FUNCTION_TFEL_TENSORIALFUNCTION_IXX */
diff --git a/include/MGIS/Function/Tensors.hxx b/include/MGIS/Function/TFEL/Tensors.hxx
similarity index 92%
rename from include/MGIS/Function/Tensors.hxx
rename to include/MGIS/Function/TFEL/Tensors.hxx
index 67edd201b..f2b672ba8 100644
--- a/include/MGIS/Function/Tensors.hxx
+++ b/include/MGIS/Function/TFEL/Tensors.hxx
@@ -1,5 +1,5 @@
 /*!
- * \file   MGIS/Function/Tensors.hxx
+ * \file   MGIS/Function/TFEL/Tensors.hxx
  * \brief
  * \author Thomas Helfer
  * \date   11/05/2025
@@ -12,21 +12,22 @@
  *   CeCILL-C_V1-en.txt and CeCILL-C_V1-fr.txt).
  */
 
-#ifndef LIB_MGIS_FUNCTION_TENSORS_HXX
-#define LIB_MGIS_FUNCTION_TENSORS_HXX
+#ifndef MGIS_HAVE_TFEL
+#error "TFEL is required to use this header"
+#endif /* MGIS_HAVE_TFEL */
+
+#ifndef LIB_MGIS_FUNCTION_TFEL_TENSORS_HXX
+#define LIB_MGIS_FUNCTION_TFEL_TENSORS_HXX
 
 #include "MGIS/Function/FunctionConcept.hxx"
 #include "MGIS/Function/EvaluatorConcept.hxx"
-
-#ifdef MGIS_HAVE_TFEL
-
-#include "MGIS/Function/Tensors/TensorConcept.hxx"
-#include "MGIS/Function/Tensors/TensorView.hxx"
-#include "MGIS/Function/Tensors/TensorModifier.hxx"
-#include "MGIS/Function/Tensors/CoalescedMemoryAccessTensorView.hxx"
-#include "MGIS/Function/Tensors/CoalescedMemoryAccessCompositeTensorsView.hxx"
-#include "MGIS/Function/Tensors/StridedCoalescedMemoryAccessTensorView.hxx"
-#include "MGIS/Function/Tensors/StridedCoalescedMemoryAccessCompositeTensorsView.hxx"
+#include "MGIS/Function/TFEL/TensorConcept.hxx"
+#include "MGIS/Function/TFEL/TensorView.hxx"
+#include "MGIS/Function/TFEL/TensorModifier.hxx"
+#include "MGIS/Function/TFEL/CoalescedMemoryAccessTensorView.hxx"
+#include "MGIS/Function/TFEL/CoalescedMemoryAccessCompositeTensorsView.hxx"
+#include "MGIS/Function/TFEL/StridedCoalescedMemoryAccessTensorView.hxx"
+#include "MGIS/Function/TFEL/StridedCoalescedMemoryAccessCompositeTensorsView.hxx"
 
 namespace mgis::function::internals {
 
@@ -67,14 +68,16 @@ namespace mgis::function::internals {
         []<typename TensorType>(const TensorType& t,
                                 const tfel::math::tmatrix<3, 3, real>& R)  //
         requires((tfel::math::TensorConcept<TensorType>) ||
-                 (tfel::math::StensorConcept<TensorType>)) {
+                 (tfel::math::StensorConcept<TensorType>) ||
+                 (tfel::math::ST2toST2Concept<TensorType>)) {
           return tfel::math::change_basis(t, R);
         });
 
     constexpr auto operator()(const tfel::math::tmatrix<3, 3, real>& R) const {
       auto c = [R]<typename TensorType>(const TensorType& t)  //
           requires((tfel::math::TensorConcept<TensorType>) ||
-                   (tfel::math::StensorConcept<TensorType>)) {
+                   (tfel::math::StensorConcept<TensorType>) ||
+                   (tfel::math::ST2toST2Concept<TensorType>)) {
         return tfel::math::change_basis(t, R);
       };
       return internals::unary_operation_modifier<decltype(c)>(c);
@@ -111,7 +114,8 @@ namespace mgis::function::internals {
         []<typename TensorType>(const TensorType& t,
                                 const tfel::math::tmatrix<3, 3, real>& R)  //
         requires((tfel::math::TensorConcept<TensorType>) ||
-                 (tfel::math::StensorConcept<TensorType>)) {
+                 (tfel::math::StensorConcept<TensorType>) ||
+                 (tfel::math::ST2toST2Concept<TensorType>)) {
           return tfel::math::change_basis(t, tfel::math::transpose(R));
         });
 
@@ -119,7 +123,8 @@ namespace mgis::function::internals {
       auto c = [Rb = tfel::math::transpose(R)]<typename TensorType>(
           const TensorType& t)  //
           requires((tfel::math::TensorConcept<TensorType>) ||
-                   (tfel::math::StensorConcept<TensorType>)) {
+                   (tfel::math::StensorConcept<TensorType>) ||
+                   (tfel::math::ST2toST2Concept<TensorType>)) {
         return tfel::math::change_basis(t, Rb);
       };
       return internals::unary_operation_modifier<decltype(c)>(c);
@@ -377,8 +382,6 @@ namespace mgis::function {
 
 }  // end of namespace mgis::function
 
-#endif /* MGIS_HAVE_TFEL */
-
-#include "MGIS/Function/Tensors.ixx"
+#include "MGIS/Function/TFEL/Tensors.ixx"
 
-#endif /* LIB_MGIS_FUNCTION_TENSORS_HXX */
+#endif /* LIB_MGIS_FUNCTION_TFEL_TENSORS_HXX */
diff --git a/include/MGIS/Function/Tensors.ixx b/include/MGIS/Function/TFEL/Tensors.ixx
similarity index 95%
rename from include/MGIS/Function/Tensors.ixx
rename to include/MGIS/Function/TFEL/Tensors.ixx
index 084676e8e..1f54669dc 100644
--- a/include/MGIS/Function/Tensors.ixx
+++ b/include/MGIS/Function/TFEL/Tensors.ixx
@@ -1,5 +1,5 @@
 /*!
- * \file   MGIS/Function/Tensors.ixx
+ * \file   MGIS/Function/TFEL/Tensors.ixx
  * \brief
  * \author Thomas Helfer
  * \date   13/05/2025
@@ -12,8 +12,8 @@
  *   CeCILL-C_V1-en.txt and CeCILL-C_V1-fr.txt).
  */
 
-#ifndef LIB_MGIS_FUNCTION_TENSORS_IXX
-#define LIB_MGIS_FUNCTION_TENSORS_IXX
+#ifndef LIB_MGIS_FUNCTION_TFEL_TENSORS_IXX
+#define LIB_MGIS_FUNCTION_TFEL_TENSORS_IXX
 
 namespace mgis::function::customization_points {
 
@@ -108,4 +108,4 @@ namespace mgis::function {
 
 }  // end of namespace mgis::function
 
-#endif /* LIB_MGIS_FUNCTION_TENSORS_IXX */
+#endif /* LIB_MGIS_FUNCTION_TFEL_TENSORS_IXX */
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 76e4b4371..685aba8d2 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -46,6 +46,11 @@ if(enable-mgis-function)
     list(APPEND MFrontGenericInterface_SOURCES
          TensorView.cxx
          TensorModifier.cxx)
+    if(enable-mgis-function-precompiled-operations)
+      list(APPEND MFrontGenericInterface_SOURCES
+           TensorOperations.cxx
+           MechanicalOperations.cxx)
+    endif(enable-mgis-function-precompiled-operations)
   endif(MGIS_HAVE_TFEL)
 endif(enable-mgis-function)
 
diff --git a/src/CoalescedMemoryAccessFunctionView.cxx b/src/CoalescedMemoryAccessFunctionView.cxx
index 640a98ba6..975f88cc2 100644
--- a/src/CoalescedMemoryAccessFunctionView.cxx
+++ b/src/CoalescedMemoryAccessFunctionView.cxx
@@ -14,5 +14,5 @@
 
 #include "MGIS/Function/CoalescedMemoryAccessFunctionViewBase.hxx"
 #ifdef MGIS_HAVE_TFEL
-#include "MGIS/Function/Tensors/CoalescedMemoryAccessCompositeTensorsView.hxx"
+#include "MGIS/Function/TFEL/CoalescedMemoryAccessCompositeTensorsView.hxx"
 #endif /* MGIS_HAVE_TFEL */
diff --git a/src/MechanicalOperations.cxx b/src/MechanicalOperations.cxx
new file mode 100644
index 000000000..8db8f942b
--- /dev/null
+++ b/src/MechanicalOperations.cxx
@@ -0,0 +1,146 @@
+/*!
+ * \file   src/MechanicalOperations.cxx
+ * \brief
+ * \author Thomas Helfer
+ * \date   01/09/2025
+ * \copyright (C) Copyright Thomas Helfer 2018.
+ * Use, modification and distribution are subject
+ * to one of the following licences:
+ * - GNU Lesser General Public License (LGPL), Version 3.0. (See accompanying
+ *   file LGPL-3.0.txt)
+ * - CECILL-C,  Version 1.0 (See accompanying files
+ *   CeCILL-C_V1-en.txt and CeCILL-C_V1-fr.txt).
+ */
+
+#include <optional>
+#include "MGIS/Context.hxx"
+#include "MGIS/Behaviour/Hypothesis.hxx"
+#include "MGIS/Function/BasicLinearSpace.hxx"
+#include "MGIS/Function/Algorithms.hxx"
+#include "MGIS/Function/TFEL/Tensors.hxx"
+#include "MGIS/Function/TFEL/Mechanics.hxx"
+#include "MGIS/Function/TFEL/MechanicalOperations.hxx"
+
+namespace mgis::function::internals {
+
+  template <EvaluatorConcept EvaluatorType>
+  static std::optional<Function<BasicLinearSpace>> evaluate(
+      Context& ctx, const EvaluatorType& e) noexcept {
+    const auto& s = getSpace(e);
+    const auto nc = getNumberOfComponents(e);
+    if (!Function<BasicLinearSpace>::checkPreconditions(ctx, s, nc)) {
+      return {};
+    }
+    auto r = Function<BasicLinearSpace>{s, nc};
+    if (!assign(ctx, r, e)) {
+      return {};
+    }
+    return r;
+  }  // end of evaluate
+
+  static std::optional<Function<BasicLinearSpace>>
+  evaluateUnaryOperationOnSymmetricTensor(
+      Context& ctx,
+      const BasicImmutableFunctionView& f,
+      const EvaluatorModifierConcept auto& op) noexcept {
+    if (getNumberOfComponents(f) == 3) {
+      return internals::evaluate(ctx, f | as_stensor<1> | op);
+    } else if (getNumberOfComponents(f) == 4) {
+      return internals::evaluate(ctx, f | as_stensor<2> | op);
+    } else if (getNumberOfComponents(f) == 6) {
+      return internals::evaluate(ctx, f | as_stensor<3> | op);
+    }
+    return ctx.registerErrorMessage("invalid number of components");
+  }  // end of evaluateUnaryOperationOnSymmetricTensor
+
+  static std::optional<Function<BasicLinearSpace>>
+  evaluateUnaryOperationOnCauchyStressComputedFromPK1(
+      Context& ctx,
+      const BasicImmutableFunctionView& pk1,
+      const BasicImmutableFunctionView& F,
+      const EvaluatorModifierConcept auto& op) noexcept {
+    if (getNumberOfComponents(pk1) == 3) {
+      return internals::evaluate(
+          ctx, pk1 | as_tensor<1> | from_pk1_to_cauchy(F | as_tensor<1>) | op);
+    } else if (getNumberOfComponents(pk1) == 5) {
+      return internals::evaluate(
+          ctx, pk1 | as_tensor<2> | from_pk1_to_cauchy(F | as_tensor<2>) | op);
+    } else if (getNumberOfComponents(pk1) == 9) {
+      return internals::evaluate(
+          ctx, pk1 | as_tensor<3> | from_pk1_to_cauchy(F | as_tensor<3>) | op);
+    }
+    return ctx.registerErrorMessage("invalid number of components");
+  }  // end of evaluateUnaryOperationOnUnsymmetricTensor
+
+}  // namespace mgis::function::internals
+
+namespace mgis::function {
+
+  std::optional<Function<BasicLinearSpace>> computeTrace(
+      Context& ctx, const BasicImmutableFunctionView& f) noexcept {
+    return internals::evaluateUnaryOperationOnSymmetricTensor(ctx, f, trace);
+  }  // end of computeTrace
+
+  std::optional<Function<BasicLinearSpace>> computeVonMisesStress(
+      Context& ctx, const BasicImmutableFunctionView& f) noexcept {
+    return internals::evaluateUnaryOperationOnSymmetricTensor(ctx, f, vmis);
+  }  // end of computeMisesStress
+
+  std::optional<Function<BasicLinearSpace>> computeHydrostraticPressure(
+      Context& ctx, const BasicImmutableFunctionView& f) noexcept {
+    return internals::evaluateUnaryOperationOnSymmetricTensor(
+        ctx, f, hydrostatic_stress);
+  }  // end of computeHydrostraticPressure
+
+  std::optional<Function<BasicLinearSpace>> computeEigenValues(
+      Context& ctx, const BasicImmutableFunctionView& f) noexcept {
+    return internals::evaluateUnaryOperationOnSymmetricTensor(ctx, f,
+                                                              eigen_values<>);
+  }  // end of computeHydrostraticPressure
+
+  std::optional<Function<BasicLinearSpace>>
+  computeCauchyStressFromFirstPiolaKirchhoffStress(
+      Context& ctx,
+      const BasicImmutableFunctionView& pk1,
+      const BasicImmutableFunctionView& F) noexcept {
+    if (getNumberOfComponents(pk1) == 3) {
+      return internals::evaluate(
+          ctx, pk1 | as_tensor<1> | from_pk1_to_cauchy(F | as_tensor<1>));
+    } else if (getNumberOfComponents(pk1) == 5) {
+      return internals::evaluate(
+          ctx, pk1 | as_tensor<2> | from_pk1_to_cauchy(F | as_tensor<2>));
+    } else if (getNumberOfComponents(pk1) == 9) {
+      return internals::evaluate(
+          ctx, pk1 | as_tensor<3> | from_pk1_to_cauchy(F | as_tensor<3>));
+    }
+    return ctx.registerErrorMessage("invalid number of components");
+  }  // end of computeCauchyStressFromFirstPiolaKirchhoffStress
+
+  std::optional<Function<BasicLinearSpace>>
+  computeCauchyStressHydrostraticPressureFromFirstPiolaKirchhoffStress(
+      Context& ctx,
+      const BasicImmutableFunctionView& pk1,
+      const BasicImmutableFunctionView& F) noexcept {
+    return internals::evaluateUnaryOperationOnCauchyStressComputedFromPK1(
+        ctx, pk1, F, vmis);
+  }
+
+  std::optional<Function<BasicLinearSpace>>
+  computeCauchyStressVonMisesStressFromFirstPiolaKirchhoffStress(
+      Context& ctx,
+      const BasicImmutableFunctionView& pk1,
+      const BasicImmutableFunctionView& F) noexcept {
+    return internals::evaluateUnaryOperationOnCauchyStressComputedFromPK1(
+        ctx, pk1, F, vmis);
+  }  // end of computeCauchyStressVonMisesStressFromFirstPiolaKirchhoffStress
+
+  std::optional<Function<BasicLinearSpace>>
+  computeCauchyStressEigenValuesFromFirstPiolaKirchhoffStress(
+      Context& ctx,
+      const BasicImmutableFunctionView& pk1,
+      const BasicImmutableFunctionView& F) noexcept {
+    return internals::evaluateUnaryOperationOnCauchyStressComputedFromPK1(
+        ctx, pk1, F, eigen_values<>);
+  }  // end of computeStressCauchyEigenValuesFromFirstPiolaKirchhoffStress
+
+}  // end of namespace mgis::function
diff --git a/src/StridedCoalescedMemoryAccessFunctionView.cxx b/src/StridedCoalescedMemoryAccessFunctionView.cxx
index cebe1670a..a394a550a 100644
--- a/src/StridedCoalescedMemoryAccessFunctionView.cxx
+++ b/src/StridedCoalescedMemoryAccessFunctionView.cxx
@@ -14,5 +14,5 @@
 
 #include "MGIS/Function/StridedCoalescedMemoryAccessFunctionViewBase.hxx"
 #ifdef MGIS_HAVE_TFEL
-#include "MGIS/Function/Tensors/StridedCoalescedMemoryAccessCompositeTensorsView.hxx"
+#include "MGIS/Function/TFEL/StridedCoalescedMemoryAccessCompositeTensorsView.hxx"
 #endif /* MGIS_HAVE_TFEL */
diff --git a/src/TensorModifier.cxx b/src/TensorModifier.cxx
index 463216ad5..ce3256e6b 100644
--- a/src/TensorModifier.cxx
+++ b/src/TensorModifier.cxx
@@ -3,14 +3,19 @@
  * \brief
  * \author Thomas Helfer
  * \date   01/09/2025
+ * \copyright (C) Copyright Thomas Helfer 2018.
+ * Use, modification and distribution are subject
+ * to one of the following licences:
+ * - GNU Lesser General Public License (LGPL), Version 3.0. (See accompanying
+ *   file LGPL-3.0.txt)
+ * - CECILL-C,  Version 1.0 (See accompanying files
+ *   CeCILL-C_V1-en.txt and CeCILL-C_V1-fr.txt).
  */
 
-#ifdef MGIS_HAVE_TFEL
-
 #include "MGIS/Function/BasicLinearSpace.hxx"
 #include "MGIS/Function/Function.hxx"
-#include "MGIS/Function/Tensors.hxx"
-#include "MGIS/Function/Tensors/TensorModifier.hxx"
+#include "MGIS/Function/TFEL/Tensors.hxx"
+#include "MGIS/Function/TFEL/TensorModifier.hxx"
 
 namespace mgis::function {
 
@@ -27,5 +32,3 @@ namespace mgis::function {
       6);
 
 }  // end of namespace mgis::function
-
-#endif /* MGIS_HAVE_TFEL */
diff --git a/src/TensorOperations.cxx b/src/TensorOperations.cxx
new file mode 100644
index 000000000..cdc9b6ef0
--- /dev/null
+++ b/src/TensorOperations.cxx
@@ -0,0 +1,213 @@
+/*!
+ * \file   src/TensorOperations.cxx
+ * \brief
+ * \author Thomas Helfer
+ * \date   01/09/2025
+ * \copyright (C) Copyright Thomas Helfer 2018.
+ * Use, modification and distribution are subject
+ * to one of the following licences:
+ * - GNU Lesser General Public License (LGPL), Version 3.0. (See accompanying
+ *   file LGPL-3.0.txt)
+ * - CECILL-C,  Version 1.0 (See accompanying files
+ *   CeCILL-C_V1-en.txt and CeCILL-C_V1-fr.txt).
+ */
+
+#include <optional>
+#include "MGIS/Context.hxx"
+#include "MGIS/Behaviour/Hypothesis.hxx"
+#include "MGIS/Function/BasicLinearSpace.hxx"
+#include "MGIS/Function/Algorithms.hxx"
+#include "MGIS/Function/TFEL/Tensors.hxx"
+#include "MGIS/Function/TFEL/TensorOperations.hxx"
+
+namespace mgis::function::internals {
+
+  template <EvaluatorConcept EvaluatorType>
+  static std::optional<Function<BasicLinearSpace>> evaluate(
+      Context& ctx, const EvaluatorType& e) noexcept {
+    const auto& s = getSpace(e);
+    const auto nc = getNumberOfComponents(e);
+    if (!Function<BasicLinearSpace>::checkPreconditions(ctx, s, nc)) {
+      return {};
+    }
+    auto r = Function<BasicLinearSpace>{s, nc};
+    if (!assign(ctx, r, e)) {
+      return {};
+    }
+    return r;
+  }  // end of evaluate
+
+  template <typename TensorFunctionView>
+  std::optional<Function<BasicLinearSpace>> computeRotatedTensor(
+      Context& ctx,
+      const TensorFunctionView& t,
+      const BasicImmutableFunctionView& r,
+      const RotationOperation ro) noexcept {
+    const auto rm = r | as_tmatrix<3, 3>;
+    if (ro == RotationOperation::FORWARD) {
+      return internals::evaluate(ctx, t | rotate(rm));
+    } else {
+      return internals::evaluate(ctx, t | rotate_backwards(rm));
+    }
+    return ctx.registerErrorMessage("invalid number of components");
+  }  // end of computeRotatedSymmetricTensor
+
+  template <typename TensorFunctionView>
+  std::optional<Function<BasicLinearSpace>> computeRotatedTensor(
+      Context& ctx,
+      const TensorFunctionView& t,
+      const std::span<real>& r,
+      const RotationOperation ro) noexcept {
+    const auto rm = tfel::math::tmatrix<3u, 3u, real>{r.data()};
+    if (ro == RotationOperation::FORWARD) {
+      return internals::evaluate(ctx, t | rotate(rm));
+    } else {
+      return internals::evaluate(ctx, t | rotate_backwards(rm));
+    }
+    return ctx.registerErrorMessage("invalid number of components");
+  }  // end of computeRotatedSymmetricTensor
+
+}  // end of namespace mgis::function::internals
+
+namespace mgis::function {
+
+  std::optional<Function<BasicLinearSpace>> computeRotatedTensor(
+      Context& ctx,
+      const BasicImmutableFunctionView& t,
+      const BasicImmutableFunctionView& r,
+      const TensorType type,
+      const RotationOperation ro) noexcept {
+    if (type == TensorType::STENSOR) {
+      return computeRotatedSymmetricTensor(ctx, t, r, ro);
+    } else if (type == TensorType::TENSOR) {
+      return computeRotatedUnsymmetricTensor(ctx, t, r, ro);
+    } else if (type == TensorType::ST2TOST2) {
+      return computeRotatedST2toST2(ctx, t, r, ro);
+    }
+    return ctx.registerErrorMessage(
+        "computeRotatedTensor: unsupported tensor type");
+  }
+
+  std::optional<Function<BasicLinearSpace>> computeRotatedTensor(
+      Context& ctx,
+      const BasicImmutableFunctionView& t,
+      const std::span<real>& r,
+      const TensorType type,
+      const RotationOperation ro) noexcept {
+    if (type == TensorType::STENSOR) {
+      return computeRotatedSymmetricTensor(ctx, t, r, ro);
+    } else if (type == TensorType::TENSOR) {
+      return computeRotatedUnsymmetricTensor(ctx, t, r, ro);
+    } else if (type == TensorType::ST2TOST2) {
+      return computeRotatedST2toST2(ctx, t, r, ro);
+    }
+    return ctx.registerErrorMessage(
+        "computeRotatedTensor: unsupported tensor type");
+  }  // end of computeRotatedTensor
+
+  std::optional<Function<BasicLinearSpace>> computeRotatedSymmetricTensor(
+      Context& ctx,
+      const BasicImmutableFunctionView& s,
+      const BasicImmutableFunctionView& r,
+      const RotationOperation ro) noexcept {
+    if (getNumberOfComponents(s) == 3) {
+      return internals::evaluate(ctx, s);
+    } else if (getNumberOfComponents(s) == 4) {
+      return internals::computeRotatedTensor(ctx, s | as_stensor<2>, r, ro);
+    } else if (getNumberOfComponents(s) == 6) {
+      return internals::computeRotatedTensor(ctx, s | as_stensor<3>, r, ro);
+    }
+    return ctx.registerErrorMessage("invalid number of components");
+  }  // end of computeRotatedSymmetricTensor
+
+  std::optional<Function<BasicLinearSpace>> computeRotatedSymmetricTensor(
+      Context& ctx,
+      const BasicImmutableFunctionView& s,
+      const std::span<real>& r,
+      const RotationOperation ro) noexcept {
+    if (r.size() != 9u) {
+      return ctx.registerErrorMessage(
+          "computeRotatedSymmetricTensor: invalid number of values for the "
+          "rotation matrix");
+    }
+    if (getNumberOfComponents(s) == 3) {
+      return internals::evaluate(ctx, s);
+    } else if (getNumberOfComponents(s) == 4) {
+      return internals::computeRotatedTensor(ctx, s | as_stensor<2>, r, ro);
+    } else if (getNumberOfComponents(s) == 6) {
+      return internals::computeRotatedTensor(ctx, s | as_stensor<3>, r, ro);
+    }
+    return ctx.registerErrorMessage("invalid number of components");
+  }  // end of computeRotatedSymmetricTensor
+
+  std::optional<Function<BasicLinearSpace>> computeRotatedUnsymmetricTensor(
+      Context& ctx,
+      const BasicImmutableFunctionView& s,
+      const BasicImmutableFunctionView& r,
+      const RotationOperation ro) noexcept {
+    if (getNumberOfComponents(s) == 3) {
+      return internals::evaluate(ctx, s);
+    } else if (getNumberOfComponents(s) == 5) {
+      return internals::computeRotatedTensor(ctx, s | as_tensor<2>, r, ro);
+    } else if (getNumberOfComponents(s) == 9) {
+      return internals::computeRotatedTensor(ctx, s | as_tensor<3>, r, ro);
+    }
+    return ctx.registerErrorMessage("invalid number of components");
+  }  // end of computeRotatedUnsymmetricTensor
+
+  std::optional<Function<BasicLinearSpace>> computeRotatedUnsymmetricTensor(
+      Context& ctx,
+      const BasicImmutableFunctionView& s,
+      const std::span<real>& r,
+      const RotationOperation ro) noexcept {
+    if (r.size() != 9u) {
+      return ctx.registerErrorMessage(
+          "computeRotatedUnsymmetricTensor: invalid number of values for the "
+          "rotation matrix");
+    }
+    if (getNumberOfComponents(s) == 3) {
+      return internals::evaluate(ctx, s);
+    } else if (getNumberOfComponents(s) == 5) {
+      return internals::computeRotatedTensor(ctx, s | as_tensor<2>, r, ro);
+    } else if (getNumberOfComponents(s) == 9) {
+      return internals::computeRotatedTensor(ctx, s | as_tensor<3>, r, ro);
+    }
+    return ctx.registerErrorMessage("invalid number of components");
+  }  // end of computeRotatedUnsymmetricTensor
+
+  std::optional<Function<BasicLinearSpace>> computeRotatedST2toST2(
+      Context& ctx,
+      const BasicImmutableFunctionView& s,
+      const BasicImmutableFunctionView& r,
+      const RotationOperation ro) noexcept {
+    if (getNumberOfComponents(s) == 9) {
+      return internals::evaluate(ctx, s);
+    } else if (getNumberOfComponents(s) == 16) {
+      return internals::computeRotatedTensor(ctx, s | as_st2tost2<2>, r, ro);
+    } else if (getNumberOfComponents(s) == 36) {
+      return internals::computeRotatedTensor(ctx, s | as_st2tost2<3>, r, ro);
+    }
+    return ctx.registerErrorMessage("invalid number of components");
+  }  // end of computeRotatedST2toST2
+
+  std::optional<Function<BasicLinearSpace>> computeRotatedST2toST2(
+      Context& ctx,
+      const BasicImmutableFunctionView& s,
+      const std::span<real>& r,
+      const RotationOperation ro) noexcept {
+    if (r.size() != 9u) {
+      return ctx.registerErrorMessage(
+          "computeRotatedST2toST2: invalid number of values for the "
+          "rotation matrix");
+    }
+    if (getNumberOfComponents(s) == 9) {
+      return internals::evaluate(ctx, s);
+    } else if (getNumberOfComponents(s) == 16) {
+      return internals::computeRotatedTensor(ctx, s | as_st2tost2<2>, r, ro);
+    } else if (getNumberOfComponents(s) == 36) {
+      return internals::computeRotatedTensor(ctx, s | as_st2tost2<3>, r, ro);
+    }
+    return ctx.registerErrorMessage("invalid number of components");
+  }  // end of computeRotatedST2toST2
+
+}  // end of namespace mgis::function
diff --git a/src/TensorView.cxx b/src/TensorView.cxx
index c328deab3..0565d1965 100644
--- a/src/TensorView.cxx
+++ b/src/TensorView.cxx
@@ -3,14 +3,19 @@
  * \brief
  * \author Thomas Helfer
  * \date   01/09/2025
+ * \copyright (C) Copyright Thomas Helfer 2018.
+ * Use, modification and distribution are subject
+ * to one of the following licences:
+ * - GNU Lesser General Public License (LGPL), Version 3.0. (See accompanying
+ *   file LGPL-3.0.txt)
+ * - CECILL-C,  Version 1.0 (See accompanying files
+ *   CeCILL-C_V1-en.txt and CeCILL-C_V1-fr.txt).
  */
 
-#ifdef MGIS_HAVE_TFEL
-
 #include "MGIS/Function/BasicLinearSpace.hxx"
 #include "MGIS/Function/Function.hxx"
-#include "MGIS/Function/Tensors.hxx"
-#include "MGIS/Function/Tensors/TensorView.hxx"
+#include "MGIS/Function/TFEL/Tensors.hxx"
+#include "MGIS/Function/TFEL/TensorView.hxx"
 
 namespace mgis::function {
 
@@ -27,5 +32,3 @@ namespace mgis::function {
       6);
 
 }  // end of namespace mgis::function
-
-#endif /* MGIS_HAVE_TFEL */
diff --git a/tests/CoalescedMemoryAccessFunctionViewTest.cxx b/tests/CoalescedMemoryAccessFunctionViewTest.cxx
index eb1177628..70952bae3 100644
--- a/tests/CoalescedMemoryAccessFunctionViewTest.cxx
+++ b/tests/CoalescedMemoryAccessFunctionViewTest.cxx
@@ -17,7 +17,7 @@
 #include "MGIS/Function/BasicLinearSpace.hxx"
 #include "MGIS/Function/BasicLinearQuadratureSpace.hxx"
 #include "MGIS/Function/CoalescedMemoryAccessFunctionViewBase.hxx"
-#include "MGIS/Function/Tensors.hxx"
+#include "MGIS/Function/TFEL/Tensors.hxx"
 
 namespace mgis::function {}  // end of namespace mgis::function
 
diff --git a/tests/EvaluatorsTest.cxx b/tests/EvaluatorsTest.cxx
index f01455b40..f1bc71f74 100644
--- a/tests/EvaluatorsTest.cxx
+++ b/tests/EvaluatorsTest.cxx
@@ -24,7 +24,7 @@
 #include "MGIS/Function/Evaluator.hxx"
 #include "MGIS/Function/FixedSizeView.hxx"
 #include "MGIS/Function/FixedSizeModifier.hxx"
-#include "MGIS/Function/Tensors.hxx"
+#include "MGIS/Function/TFEL/Tensors.hxx"
 
 struct EvaluatorsTest final : public tfel::tests::TestCase {
   EvaluatorsTest()
diff --git a/tests/MechanicalEvaluatorsTest.cxx b/tests/MechanicalEvaluatorsTest.cxx
index 0e6e91b40..87400b0ce 100644
--- a/tests/MechanicalEvaluatorsTest.cxx
+++ b/tests/MechanicalEvaluatorsTest.cxx
@@ -21,7 +21,7 @@
 #include "MGIS/Function/Function.hxx"
 #include "MGIS/Function/FixedSizeView.hxx"
 #include "MGIS/Function/FixedSizeModifier.hxx"
-#include "MGIS/Function/Mechanics.hxx"
+#include "MGIS/Function/TFEL/Mechanics.hxx"
 
 struct MechanicalEvaluatorsTest final : public tfel::tests::TestCase {
   MechanicalEvaluatorsTest()
diff --git a/tests/StridedCoalescedMemoryAccessFunctionViewTest.cxx b/tests/StridedCoalescedMemoryAccessFunctionViewTest.cxx
index a3eb9e367..d21c170ff 100644
--- a/tests/StridedCoalescedMemoryAccessFunctionViewTest.cxx
+++ b/tests/StridedCoalescedMemoryAccessFunctionViewTest.cxx
@@ -17,7 +17,7 @@
 #include "MGIS/Function/BasicLinearSpace.hxx"
 #include "MGIS/Function/BasicLinearQuadratureSpace.hxx"
 #include "MGIS/Function/StridedCoalescedMemoryAccessFunctionViewBase.hxx"
-#include "MGIS/Function/Tensors.hxx"
+#include "MGIS/Function/TFEL/Tensors.hxx"
 
 namespace mgis::function {}  // end of namespace mgis::function
 
diff --git a/tests/TensorialFunctionTest.cxx b/tests/TensorialFunctionTest.cxx
index 46747c30b..0f468e43b 100644
--- a/tests/TensorialFunctionTest.cxx
+++ b/tests/TensorialFunctionTest.cxx
@@ -25,8 +25,8 @@
 #include "MGIS/Function/Evaluator.hxx"
 #include "MGIS/Function/FixedSizeView.hxx"
 #include "MGIS/Function/FixedSizeModifier.hxx"
-#include "MGIS/Function/Tensors.hxx"
-#include "MGIS/Function/TensorialFunction.hxx"
+#include "MGIS/Function/TFEL/Tensors.hxx"
+#include "MGIS/Function/TFEL/TensorialFunction.hxx"
 
 struct TensorialFunctionsTest final : public tfel::tests::TestCase {
   TensorialFunctionsTest()
diff --git a/tests/UniformEvaluatorsTest.cxx b/tests/UniformEvaluatorsTest.cxx
index e74d8873f..cb22009c1 100644
--- a/tests/UniformEvaluatorsTest.cxx
+++ b/tests/UniformEvaluatorsTest.cxx
@@ -20,7 +20,7 @@
 #include "TFEL/Tests/TestManager.hxx"
 #include "MGIS/Function/BasicLinearSpace.hxx"
 #include "MGIS/Function/UniformEvaluator.hxx"
-#include "MGIS/Function/Tensors.hxx"
+#include "MGIS/Function/TFEL/Tensors.hxx"
 
 struct UniformEvaluatorsTest final : public tfel::tests::TestCase {
   UniformEvaluatorsTest()