diff --git a/include/NeoFOAM/DSL/coeff.hpp b/include/NeoFOAM/dsl/coeff.hpp
similarity index 97%
rename from include/NeoFOAM/DSL/coeff.hpp
rename to include/NeoFOAM/dsl/coeff.hpp
index d2b2a6623..cd91ecdb7 100644
--- a/include/NeoFOAM/DSL/coeff.hpp
+++ b/include/NeoFOAM/dsl/coeff.hpp
@@ -2,12 +2,12 @@
 // SPDX-FileCopyrightText: 2023 NeoFOAM authors
 #pragma once
 
-namespace NeoFOAM::DSL
+namespace NeoFOAM::dsl
 {
 
 /**
  * @class Coeff
- * @brief A class that represents a coefficient for the NeoFOAM DSL.
+ * @brief A class that represents a coefficient for the NeoFOAM dsl.
  *
  * This class stores a single scalar coefficient and optionally span of values.
  * It is used to delay the evaluation of a scalar multiplication with a field to
@@ -107,4 +107,4 @@ inline Coeff operator*(const Coeff& lhs, const Coeff& rhs)
     return result;
 }
 
-} // namespace NeoFOAM::DSL
+} // namespace NeoFOAM::dsl
diff --git a/include/NeoFOAM/DSL/equation.hpp b/include/NeoFOAM/dsl/equation.hpp
similarity index 98%
rename from include/NeoFOAM/DSL/equation.hpp
rename to include/NeoFOAM/dsl/equation.hpp
index 87c2f6b01..86ee0109d 100644
--- a/include/NeoFOAM/DSL/equation.hpp
+++ b/include/NeoFOAM/dsl/equation.hpp
@@ -9,10 +9,10 @@
 
 #include "NeoFOAM/core/primitives/scalar.hpp"
 #include "NeoFOAM/fields/field.hpp"
-#include "NeoFOAM/DSL/operator.hpp"
+#include "NeoFOAM/dsl/operator.hpp"
 #include "NeoFOAM/core/error.hpp"
 
-namespace NeoFOAM::DSL
+namespace NeoFOAM::dsl
 {
 
 class Equation
@@ -189,4 +189,4 @@ Equation operator-(const Operator& lhs, const Operator& rhs)
     return equation;
 }
 
-} // namespace NeoFOAM::DSL
+} // namespace NeoFOAM::dsl
diff --git a/include/NeoFOAM/DSL/operator.hpp b/include/NeoFOAM/dsl/operator.hpp
similarity index 95%
rename from include/NeoFOAM/DSL/operator.hpp
rename to include/NeoFOAM/dsl/operator.hpp
index 64480b7f8..8392a8591 100644
--- a/include/NeoFOAM/DSL/operator.hpp
+++ b/include/NeoFOAM/dsl/operator.hpp
@@ -10,15 +10,11 @@
 
 #include "NeoFOAM/core/primitives/scalar.hpp"
 #include "NeoFOAM/fields/field.hpp"
-#include "NeoFOAM/core/parallelAlgorithms.hpp"
-#include "NeoFOAM/finiteVolume/cellCentred/fields/volumeField.hpp"
 #include "NeoFOAM/core/input.hpp"
-#include "NeoFOAM/DSL/coeff.hpp"
+#include "NeoFOAM/dsl/coeff.hpp"
 
 
-namespace fvcc = NeoFOAM::finiteVolume::cellCentred;
-
-namespace NeoFOAM::DSL
+namespace NeoFOAM::dsl
 {
 
 template<typename T>
@@ -38,10 +34,10 @@ concept HasExplicitOperator = requires(T t) {
 
 /* @class OperatorMixin
  * @brief A mixin class to represent simplify implementations of concrete operators
- * in NeoFOAMs DSL
+ * in NeoFOAMs dsl
  *
  *
- * @ingroup DSL
+ * @ingroup dsl
  */
 class OperatorMixin
 {
@@ -70,7 +66,7 @@ class OperatorMixin
 
 
 /* @class Operator
- * @brief A class to represent a operator in NeoFOAMs DSL
+ * @brief A class to represent a operator in NeoFOAMs dsl
  *
  * The design here is based on the type erasure design pattern
  * see https://www.youtube.com/watch?v=4eeESJQk-mw
@@ -79,7 +75,7 @@ class OperatorMixin
  * of Operators e.g Divergence, Laplacian, etc can be stored in a vector of
  * Operators
  *
- * @ingroup DSL
+ * @ingroup dsl
  */
 class Operator
 {
@@ -251,4 +247,4 @@ Operator operator*(CoeffFunction coeffFunc, const Operator& lhs)
     return result;
 }
 
-} // namespace NeoFOAM::DSL
+} // namespace NeoFOAM::dsl
diff --git a/include/NeoFOAM/finiteVolume/cellCentred/timeIntegration/forwardEuler.hpp b/include/NeoFOAM/dsl/timeIntegration/forwardEuler.hpp
similarity index 72%
rename from include/NeoFOAM/finiteVolume/cellCentred/timeIntegration/forwardEuler.hpp
rename to include/NeoFOAM/dsl/timeIntegration/forwardEuler.hpp
index 3d8b24e96..b5879fa3a 100644
--- a/include/NeoFOAM/finiteVolume/cellCentred/timeIntegration/forwardEuler.hpp
+++ b/include/NeoFOAM/dsl/timeIntegration/forwardEuler.hpp
@@ -7,10 +7,7 @@
 #include <functional>
 
 #include "NeoFOAM/fields/field.hpp"
-#include "NeoFOAM/core/executor/executor.hpp"
-#include "NeoFOAM/finiteVolume/cellCentred/timeIntegration/timeIntegration.hpp"
-#include "NeoFOAM/mesh/unstructured.hpp"
-
+#include "NeoFOAM/dsl/timeIntegration/timeIntegration.hpp"
 
 namespace NeoFOAM::finiteVolume::cellCentred
 {
@@ -20,7 +17,7 @@ class ForwardEuler : public TimeIntegrationFactory::Register<ForwardEuler>
 
 public:
 
-    ForwardEuler(const DSL::Equation& eqnSystem, const Dictionary& dict);
+    ForwardEuler(const dsl::Equation& eqnSystem, const Dictionary& dict);
 
     static std::string name() { return "forwardEuler"; }
 
diff --git a/include/NeoFOAM/finiteVolume/cellCentred/timeIntegration/timeIntegration.hpp b/include/NeoFOAM/dsl/timeIntegration/timeIntegration.hpp
similarity index 83%
rename from include/NeoFOAM/finiteVolume/cellCentred/timeIntegration/timeIntegration.hpp
rename to include/NeoFOAM/dsl/timeIntegration/timeIntegration.hpp
index b6d7cc8e5..890875efa 100644
--- a/include/NeoFOAM/finiteVolume/cellCentred/timeIntegration/timeIntegration.hpp
+++ b/include/NeoFOAM/dsl/timeIntegration/timeIntegration.hpp
@@ -7,9 +7,8 @@
 #include "NeoFOAM/core/executor/executor.hpp"
 #include "NeoFOAM/mesh/unstructured.hpp"
 #include "NeoFOAM/finiteVolume/cellCentred.hpp"
-
-#include "NeoFOAM/DSL/operator.hpp"
-#include "NeoFOAM/DSL/equation.hpp"
+#include "NeoFOAM/dsl/operator.hpp"
+#include "NeoFOAM/dsl/equation.hpp"
 
 #include <functional>
 
@@ -19,14 +18,14 @@ namespace NeoFOAM
 class TimeIntegrationFactory :
     public RuntimeSelectionFactory<
         TimeIntegrationFactory,
-        Parameters<const DSL::Equation&, const Dictionary&>>
+        Parameters<const dsl::Equation&, const Dictionary&>>
 {
 
 public:
 
     static std::string name() { return "timeIntegrationFactory"; }
 
-    TimeIntegrationFactory(const DSL::Equation& eqnSystem, const Dictionary& dict)
+    TimeIntegrationFactory(const dsl::Equation& eqnSystem, const Dictionary& dict)
         : eqnSystem_(eqnSystem), dict_(dict)
     {}
 
@@ -39,7 +38,7 @@ class TimeIntegrationFactory :
 
 protected:
 
-    DSL::Equation eqnSystem_;
+    dsl::Equation eqnSystem_;
 
     const Dictionary& dict_;
 };
@@ -55,7 +54,7 @@ class TimeIntegration
     TimeIntegration(TimeIntegration&& timeIntegrate)
         : timeIntegrateStrategy_(std::move(timeIntegrate.timeIntegrateStrategy_)) {};
 
-    TimeIntegration(const DSL::Equation& eqnSystem, const Dictionary& dict)
+    TimeIntegration(const dsl::Equation& eqnSystem, const Dictionary& dict)
         : timeIntegrateStrategy_(
             TimeIntegrationFactory::create(dict.get<std::string>("type"), eqnSystem, dict)
         ) {};
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 86bf09ce3..13fbdd2ab 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -30,7 +30,7 @@ target_sources(
           "finiteVolume/cellCentred/operators/gaussGreenDiv.cpp"
           "finiteVolume/cellCentred/interpolation/linear.cpp"
           "finiteVolume/cellCentred/interpolation/upwind.cpp"
-          "finiteVolume/cellCentred/timeIntegration/forwardEuler.cpp")
+          "dsl/timeIntegration/forwardEuler.cpp")
 
 include(${CMAKE_SOURCE_DIR}/cmake/Sanitizer.cmake)
 enable_sanitizers(
diff --git a/src/finiteVolume/cellCentred/timeIntegration/forwardEuler.cpp b/src/dsl/timeIntegration/forwardEuler.cpp
similarity index 90%
rename from src/finiteVolume/cellCentred/timeIntegration/forwardEuler.cpp
rename to src/dsl/timeIntegration/forwardEuler.cpp
index 8e80367ba..4d21498b9 100644
--- a/src/finiteVolume/cellCentred/timeIntegration/forwardEuler.cpp
+++ b/src/dsl/timeIntegration/forwardEuler.cpp
@@ -3,9 +3,8 @@
 
 #include <memory>
 
-#include "NeoFOAM/finiteVolume/cellCentred/timeIntegration/forwardEuler.hpp"
+#include "NeoFOAM/dsl/timeIntegration/forwardEuler.hpp"
 #include "NeoFOAM/core/error.hpp"
-#include "NeoFOAM/core/parallelAlgorithms.hpp"
 
 namespace NeoFOAM::finiteVolume::cellCentred
 {
diff --git a/test/CMakeLists.txt b/test/CMakeLists.txt
index 80d8ffdce..25609aff4 100644
--- a/test/CMakeLists.txt
+++ b/test/CMakeLists.txt
@@ -6,7 +6,8 @@ list(APPEND CMAKE_MODULE_PATH ${Catch2_SOURCE_DIR}/extras)
 # has to be first since it adds the main target
 add_subdirectory(catch2)
 
-# This function creates unit tests. It allows the following keywords:
+# include "NeoFOAM/core/parallelAlgorithms.hpp" This function creates unit tests. It allows the
+# following keywords:
 #
 # * MPI_SIZE: the number of MPI processors to be used, defaults to 1 if not set
 # * COMMAND: the test command (same behavior as for CMake's add_test), defaults to the test name
diff --git a/test/dsl/coeff.cpp b/test/dsl/coeff.cpp
index e7c33958e..583fcbd18 100644
--- a/test/dsl/coeff.cpp
+++ b/test/dsl/coeff.cpp
@@ -8,12 +8,12 @@
 #include <catch2/benchmark/catch_benchmark.hpp>
 
 #include "NeoFOAM/fields/field.hpp"
-#include "NeoFOAM/DSL/coeff.hpp"
+#include "NeoFOAM/dsl/coeff.hpp"
 
 using Field = NeoFOAM::Field<NeoFOAM::scalar>;
-using Coeff = NeoFOAM::DSL::Coeff;
+using Coeff = NeoFOAM::dsl::Coeff;
 
-namespace detail = NeoFOAM::DSL::detail;
+namespace detail = NeoFOAM::dsl::detail;
 
 
 TEST_CASE("Coeff")
diff --git a/test/dsl/common.hpp b/test/dsl/common.hpp
index 434c78e7f..ede411279 100644
--- a/test/dsl/common.hpp
+++ b/test/dsl/common.hpp
@@ -8,17 +8,19 @@
 #include <catch2/benchmark/catch_benchmark.hpp>
 
 #include "NeoFOAM/fields/field.hpp"
-#include "NeoFOAM/DSL/coeff.hpp"
-#include "NeoFOAM/DSL/operator.hpp"
+#include "NeoFOAM/finiteVolume/cellCentred/fields/volumeField.hpp"
+#include "NeoFOAM/dsl/coeff.hpp"
+#include "NeoFOAM/dsl/operator.hpp"
+
+namespace fvcc = NeoFOAM::finiteVolume::cellCentred;
 
 using Field = NeoFOAM::Field<NeoFOAM::scalar>;
-using Coeff = NeoFOAM::DSL::Coeff;
-using Operator = NeoFOAM::DSL::Operator;
-using OperatorMixin = NeoFOAM::DSL::OperatorMixin;
+using Coeff = NeoFOAM::dsl::Coeff;
+using Operator = NeoFOAM::dsl::Operator;
+using OperatorMixin = NeoFOAM::dsl::OperatorMixin;
 using Executor = NeoFOAM::Executor;
 using VolumeField = fvcc::VolumeField<NeoFOAM::scalar>;
 using BoundaryFields = NeoFOAM::BoundaryFields<NeoFOAM::scalar>;
-namespace fvcc = NeoFOAM::finiteVolume::cellCentred;
 
 /* A dummy implementation of a Operator
  * following the Operator interface */
diff --git a/test/dsl/equation.cpp b/test/dsl/equation.cpp
index 11d917a71..42d818ae1 100644
--- a/test/dsl/equation.cpp
+++ b/test/dsl/equation.cpp
@@ -3,9 +3,9 @@
 #define CATCH_CONFIG_RUNNER // Define this before including catch.hpp to create
                             // a custom main
 #include "common.hpp"
-#include "NeoFOAM/DSL/equation.hpp"
+#include "NeoFOAM/dsl/equation.hpp"
 
-using Equation = NeoFOAM::DSL::Equation;
+using Equation = NeoFOAM::dsl::Equation;
 
 TEST_CASE("Equation")
 {
diff --git a/test/finiteVolume/cellCentred/timeIntegration/CMakeLists.txt b/test/dsl/timeIntegration/CMakeLists.txt
similarity index 100%
rename from test/finiteVolume/cellCentred/timeIntegration/CMakeLists.txt
rename to test/dsl/timeIntegration/CMakeLists.txt
diff --git a/test/finiteVolume/cellCentred/timeIntegration/timeIntegration.cpp b/test/dsl/timeIntegration/timeIntegration.cpp
similarity index 100%
rename from test/finiteVolume/cellCentred/timeIntegration/timeIntegration.cpp
rename to test/dsl/timeIntegration/timeIntegration.cpp
diff --git a/test/finiteVolume/CMakeLists.txt b/test/finiteVolume/CMakeLists.txt
index 7213b6f5a..564d38f7b 100644
--- a/test/finiteVolume/CMakeLists.txt
+++ b/test/finiteVolume/CMakeLists.txt
@@ -4,4 +4,3 @@
 add_subdirectory(cellCentred/fields)
 add_subdirectory(cellCentred/boundary)
 add_subdirectory(cellCentred/interpolation)
-add_subdirectory(cellCentred/timeIntegration)