diff --git a/src/eckit/option/FactoryOption.cc b/src/eckit/option/FactoryOption.cc
index 8276eeee6..893bc3525 100644
--- a/src/eckit/option/FactoryOption.cc
+++ b/src/eckit/option/FactoryOption.cc
@@ -16,15 +16,11 @@
 
 #include <iostream>
 
-#include "eckit/config/Configuration.h"
 #include "eckit/config/Configured.h"
-
 #include "eckit/exception/Exceptions.h"
 #include "eckit/option/FactoryOption.h"
-#include "eckit/utils/Translator.h"
 
-namespace eckit {
-namespace option {
+namespace eckit::option {
 
 
 template <class T>
@@ -62,11 +58,9 @@ void FactoryOption<T>::copy(const Configuration& from, Configured& to) const {
 
 template <class T>
 void FactoryOption<T>::print(std::ostream& out) const {
-    out << "   --" << name_ << "=name"
-        << " (" << description_ << ")";
+    out << "   --" << name_ << "=name" << " (" << description_ << ")";
     out << std::endl << "     Values are: ";
     T::list(out);
 }
 
-}  // namespace option
-}  // namespace eckit
+}  // namespace eckit::option
diff --git a/src/eckit/option/FactoryOption.h b/src/eckit/option/FactoryOption.h
index 073a24351..025849003 100644
--- a/src/eckit/option/FactoryOption.h
+++ b/src/eckit/option/FactoryOption.h
@@ -12,9 +12,7 @@
 /// @author Tiago Quintino
 /// @date Apr 2015
 
-
-#ifndef eckit_option_FactoryOption_H
-#define eckit_option_FactoryOption_H
+#pragma once
 
 #include <iosfwd>
 
@@ -52,5 +50,3 @@ class FactoryOption : public BaseOption<std::string> {
 }  // namespace eckit::option
 
 #include "eckit/option/FactoryOption.cc"
-
-#endif
diff --git a/src/eckit/option/MultiValueOption.cc b/src/eckit/option/MultiValueOption.cc
index 5b1cd8212..fef4ee220 100644
--- a/src/eckit/option/MultiValueOption.cc
+++ b/src/eckit/option/MultiValueOption.cc
@@ -13,9 +13,7 @@
 #include <algorithm>
 #include <iostream>
 
-#include "eckit/config/Configuration.h"
 #include "eckit/config/Configured.h"
-
 #include "eckit/exception/Exceptions.h"
 
 namespace eckit::option {
@@ -39,16 +37,15 @@ MultiValueOption::MultiValueOption(const std::string& name, const std::string& d
                                    size_t n_optional_values, std::optional<values_t> default_values) :
     base_t(name, description, std::move(default_values)),
     n_mandatory_values_{n_mandatory_values},
-    n_optional_values_{n_optional_values},
-    values_{} {
+    n_optional_values_{n_optional_values} {
     ASSERT_MSG(n_mandatory_values >= 1, "At least 1 mandatory value is expected.");
 }
 
 size_t MultiValueOption::set(Configured& parametrisation, [[maybe_unused]] size_t values, args_t::const_iterator begin,
                              args_t::const_iterator end) const {
     if (std::distance(begin, end) < n_mandatory_values_) {
-        throw UserError("Not enough option values found for MultiValueOption, where at least " +
-                        std::to_string(n_mandatory_values_) + " were expected");
+        throw UserError("Not enough option values found for MultiValueOption, where at least "
+                        + std::to_string(n_mandatory_values_) + " were expected");
     }
 
     // Collect n_mandatory_values_ mandatory values from the range [begin, end)
diff --git a/src/eckit/option/MultiValueOption.h b/src/eckit/option/MultiValueOption.h
index fd4108360..9d6998e16 100644
--- a/src/eckit/option/MultiValueOption.h
+++ b/src/eckit/option/MultiValueOption.h
@@ -8,8 +8,7 @@
  * does it submit to any jurisdiction.
  */
 
-#ifndef eckit_option_MultiValueOption_H
-#define eckit_option_MultiValueOption_H
+#pragma once
 
 #include <iosfwd>
 
@@ -23,9 +22,12 @@ class MultiValueOption : public BaseOption<std::vector<std::string>> {
     using values_t = std::vector<std::string>;
 
     MultiValueOption(const std::string& name, const std::string& description, size_t n_mandatory_values);
-    MultiValueOption(const std::string& name, const std::string& description, size_t n_mandatory_values, size_t n_optional_values);
-    MultiValueOption(const std::string& name, const std::string& description, size_t n_mandatory_values, const values_t& default_values);
-    MultiValueOption(const std::string& name, const std::string& description, size_t n_mandatory_values, size_t n_optional_values, const values_t& default_values);
+    MultiValueOption(const std::string& name, const std::string& description, size_t n_mandatory_values,
+                     size_t n_optional_values);
+    MultiValueOption(const std::string& name, const std::string& description, size_t n_mandatory_values,
+                     const values_t& default_values);
+    MultiValueOption(const std::string& name, const std::string& description, size_t n_mandatory_values,
+                     size_t n_optional_values, const values_t& default_values);
     ~MultiValueOption() override = default;
 
     size_t set(Configured&, size_t values, args_t::const_iterator begin, args_t::const_iterator end) const override;
@@ -33,7 +35,8 @@ class MultiValueOption : public BaseOption<std::vector<std::string>> {
     void print(std::ostream&) const override;
 
 private:
-    MultiValueOption(const std::string& name, const std::string& description, size_t n_mandatory_values, size_t n_maximum_values, std::optional<values_t> default_values);
+    MultiValueOption(const std::string& name, const std::string& description, size_t n_mandatory_values,
+                     size_t n_maximum_values, std::optional<values_t> default_values);
 
     void set_value(const values_t& values, Configured&) const override;
 
@@ -47,5 +50,3 @@ class MultiValueOption : public BaseOption<std::vector<std::string>> {
 };
 
 }  // namespace eckit::option
-
-#endif
diff --git a/src/eckit/option/SimpleOption.cc b/src/eckit/option/SimpleOption.cc
index ea1bb4de3..a816643f8 100644
--- a/src/eckit/option/SimpleOption.cc
+++ b/src/eckit/option/SimpleOption.cc
@@ -18,7 +18,6 @@
 
 #include "eckit/config/Configuration.h"
 #include "eckit/config/Configured.h"
-
 #include "eckit/exception/Exceptions.h"
 #include "eckit/filesystem/PathName.h"
 #include "eckit/option/SimpleOption.h"
@@ -68,12 +67,12 @@ void SimpleOption<T>::set_value(const T& value, Configured& parametrisation) con
 
 template <class T>
 T SimpleOption<T>::translate(const std::string& value) const {
-    T v = eckit::Translator<std::string, T>()(value);
+    T v = Translator<std::string, T>()(value);
     return v;
 }
 
 template <>
-inline void SimpleOption<eckit::PathName>::copy(const Configuration& from, Configured& to) const {
+inline void SimpleOption<PathName>::copy(const Configuration& from, Configured& to) const {
     std::string v;
     if (from.get(name_, v)) {
         to.set(name_, v);
diff --git a/src/eckit/option/SimpleOption.h b/src/eckit/option/SimpleOption.h
index 168401529..6bd3c8a20 100644
--- a/src/eckit/option/SimpleOption.h
+++ b/src/eckit/option/SimpleOption.h
@@ -12,9 +12,7 @@
 /// @author Tiago Quintino
 /// @date Apr 2015
 
-
-#ifndef eckit_option_SimpleOption_H
-#define eckit_option_SimpleOption_H
+#pragma once
 
 #include <iosfwd>
 
@@ -39,7 +37,6 @@ class SimpleOption : public BaseOption<T> {
     void print(std::ostream&) const override;
 
 private:
-
     void set_value(const T& value, Configured&) const override;
 
     [[nodiscard]] T translate(const std::string& value) const override;
@@ -50,5 +47,3 @@ class SimpleOption : public BaseOption<T> {
 }  // namespace eckit::option
 
 #include "eckit/option/SimpleOption.cc"
-
-#endif
diff --git a/src/eckit/option/VectorOption.cc b/src/eckit/option/VectorOption.cc
index 3f612568d..66ba5efbc 100644
--- a/src/eckit/option/VectorOption.cc
+++ b/src/eckit/option/VectorOption.cc
@@ -23,13 +23,7 @@
 #include "eckit/utils/Tokenizer.h"
 #include "eckit/utils/Translator.h"
 
-
-namespace eckit {
-
-namespace option {
-
-//----------------------------------------------------------------------------------------------------------------------
-
+namespace eckit::option {
 
 template <class T>
 VectorOption<T>::VectorOption(const std::string& name, const std::string& description, size_t size,
@@ -61,9 +55,9 @@ void VectorOption<T>::set_value(const std::vector<T>& value, Configured& paramet
 
 template <class T>
 std::vector<T> VectorOption<T>::translate(const std::string& value) const {
-    eckit::Translator<std::string, T> t;
+    Translator<std::string, T> t;
 
-    eckit::Tokenizer parse(separator_);
+    Tokenizer parse(separator_);
     std::vector<std::string> tokens;
     parse(value, tokens);
 
@@ -97,16 +91,9 @@ void VectorOption<T>::print(std::ostream& out) const {
     out << " (" << this->description() << ")";
 }
 
-
 template <class T>
 void VectorOption<T>::copy(const Configuration& from, Configured& to) const {
     Option::copy<std::vector<T>>(this->name(), from, to);
 }
 
-
-//----------------------------------------------------------------------------------------------------------------------
-
-
-}  // namespace option
-
-}  // namespace eckit
+}  // namespace eckit::option
diff --git a/src/eckit/option/VectorOption.h b/src/eckit/option/VectorOption.h
index 5a49817dc..84b6a57a9 100644
--- a/src/eckit/option/VectorOption.h
+++ b/src/eckit/option/VectorOption.h
@@ -13,8 +13,7 @@
 /// @date Apr 2015
 
 
-#ifndef VectorOption_H
-#define VectorOption_H
+#pragma once
 
 #include <iosfwd>
 
@@ -33,7 +32,8 @@ class VectorOption : public BaseOption<std::vector<T>> {
     // -- Contructors
 
     VectorOption(const std::string& name, const std::string& description, size_t size, const char* separator = "/");
-    VectorOption(const std::string& name, const std::string& description, size_t size, const std::vector<T>& default_value, const char* separator = "/");
+    VectorOption(const std::string& name, const std::string& description, size_t size,
+                 const std::vector<T>& default_value, const char* separator = "/");
 
     // -- Destructor
 
@@ -106,5 +106,3 @@ class VectorOption : public BaseOption<std::vector<T>> {
 }  // namespace eckit::option
 
 #include "eckit/option/VectorOption.cc"
-
-#endif