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+## Version 4.0 (09-21-2021)
+
+### Added
+  
+- pybind11 binding
+- contact mechanics model
+- phase field model
+- Added a Changelog
+
+### Changed
+
+- transferred CI from jenkinsfile to gitlab CI/CD
+- API changes to make container mode STL compatible
+  - clear does not set to 0 anymore but empties containers
+  - empty does not empty containers but tells if the container is empty
+  - zero replace the old empty and set containers to 0
+  
+### Deprecated
+
+- `getForce` in the `SolidMechanicsModel` becomes `getExternalForce`
+- `firstType()`, `lastType()` replaced by `elementTypes()`
+
+## Version 3.2 (not released)
+
+### Added
+
+- Activating PETSc solver back with the new solver interface
+
+### Deprecated 
+
+- deprecating old C++ 03 code
+
+
+## 3.0 (2018-03)
+
+### Added
+
+- Parallel cohesive elements
+- Element groups created by default for “physical_names”
+- Named arguments for functions (e.g. model.initFull(_analysis_method = _static))
+
+### Changed
+
+- Models using new interface for solvers
+  - Same configuration for all models
+  - Solver can be configured in input file
+- Only one function to solve a step model.solveStep()
+- Simplification of the parallel simulation with the mesh.distribute() function
+- Switch from C++ standard 2003 to 2014 Example of changes implied by this:
+
+   for (UInt g = _not_ghost; g <= _ghost; ++g) {
+      GhostType gt = (GhostType)g;
+      Mesh::type_iterator it = this->mesh.firstType(spatial_dimension, gt);
+      Mesh::type_iterator end = this->mesh.lastType(spatial_dimension, gt);
+      for (; it != end; ++it) {
+        ElementType & type = *it;
+        ...
+      }
+    }
+
+  becomes:
+
+    for (auto ghost_type : ghost_types) {
+      for (auto type : mesh.elementTypes(spatial_dimension,
+                                         ghost_type)) {
+        ...
+      }
+    }
+
+### Deleted
+
+- PETSc interface temporary inactive
+- Periodic boundary condition temporary inactive
+
+## 2.3 (2016-03)
+
+### Added
+
+- swig python interface
+
+## 2.2 (2014-09)
+
+### Added
+- Cohesive elements
+
+## 1.0 (2012-06)
+
+### Added
+- Continuum damage local and non-local
+- Models: solid mechanics, structural mechanics, heat transfer
+