diff --git a/apps/graph/list/storage_list_controller.cpp b/apps/graph/list/storage_list_controller.cpp
index da9f23889..6beb1cd82 100644
--- a/apps/graph/list/storage_list_controller.cpp
+++ b/apps/graph/list/storage_list_controller.cpp
@@ -64,11 +64,11 @@ bool StorageListController::textFieldDidFinishEditing(TextField * textField, con
   }
 
   // Delete any variable with the same name
-  GlobalContext::DestroyRecordsBaseNamedWithoutExtension(baseName, GlobalContext::funcExtension /*TODO store elsewhere?*/);
+  GlobalContext::DestroyRecordsBaseNamedWithoutExtension(baseName, Ion::Storage::funcExtension);
 
   // Set the name
   StorageFunction::NameNotCompliantError nameError = StorageFunction::NameNotCompliantError::None;
-  Ion::Storage::Record::ErrorStatus error = StorageFunction::BaseNameCompliant(baseName, &nameError) ? modelStore()->recordAtIndex(m_selectableTableView.selectedRow()).setBaseNameWithExtension(baseName, GlobalContext::funcExtension /*TODO store elsewhere?*/) : Ion::Storage::Record::ErrorStatus::NonCompliantName;
+  Ion::Storage::Record::ErrorStatus error = StorageFunction::BaseNameCompliant(baseName, &nameError) ? modelStore()->recordAtIndex(m_selectableTableView.selectedRow()).setBaseNameWithExtension(baseName, Ion::Storage::funcExtension) : Ion::Storage::Record::ErrorStatus::NonCompliantName;
 
   // Handle any error
   if (error == Ion::Storage::Record::ErrorStatus::None) {
diff --git a/apps/graph/storage_cartesian_function_store.h b/apps/graph/storage_cartesian_function_store.h
index ee786cfcb..0f21a9cf1 100644
--- a/apps/graph/storage_cartesian_function_store.h
+++ b/apps/graph/storage_cartesian_function_store.h
@@ -15,7 +15,7 @@ public:
   char unknownSymbol() const override { return Poincare::Symbol::SpecialSymbols::UnknownX; }
 private:
   Ion::Storage::Record::ErrorStatus addEmptyModel() override;
-  const char * modelExtension() const override { return Shared::GlobalContext::funcExtension; }
+  const char * modelExtension() const override { return Ion::Storage::funcExtension; }
   void setMemoizedModelAtIndex(int cacheIndex, Ion::Storage::Record record) const override;
   Shared::SingleExpressionModelHandle * memoizedModelAtIndex(int cacheIndex) const override;
   mutable Shared::StorageCartesianFunction m_functions[k_maxNumberOfMemoizedModels];
diff --git a/apps/sequence/sequence_store.cpp b/apps/sequence/sequence_store.cpp
index 718a3e3d3..6ede5a26a 100644
--- a/apps/sequence/sequence_store.cpp
+++ b/apps/sequence/sequence_store.cpp
@@ -14,7 +14,7 @@ const char * SequenceStore::firstAvailableName(int * nameIndex) {
   int currentNameIndex = 0;
   while (currentNameIndex < MaxNumberOfSequences) {
     const char * name = k_sequenceNames[currentNameIndex];
-    if (Ion::Storage::sharedStorage()->recordBaseNamedWithExtension(name, Shared::GlobalContext::seqExtension).isNull()) {
+    if (Ion::Storage::sharedStorage()->recordBaseNamedWithExtension(name, Ion::Storage::seqExtension).isNull()) {
       if (nameIndex) {
         *nameIndex = currentNameIndex;
       }
diff --git a/apps/sequence/sequence_store.h b/apps/sequence/sequence_store.h
index 383499e6a..3db947705 100644
--- a/apps/sequence/sequence_store.h
+++ b/apps/sequence/sequence_store.h
@@ -30,7 +30,7 @@ public:
   };
 
 private:
-  const char * modelExtension() const override { return Shared::GlobalContext::seqExtension; }
+  const char * modelExtension() const override { return Ion::Storage::seqExtension; }
   /* We don't really use model memoization as the number of Sequence is limited
    * and we keep enough Sequences to store them all. */
   void setMemoizedModelAtIndex(int cacheIndex, Ion::Storage::Record record) const override;
diff --git a/apps/shared/global_context.cpp b/apps/shared/global_context.cpp
index 48386b2a5..9904d433d 100644
--- a/apps/shared/global_context.cpp
+++ b/apps/shared/global_context.cpp
@@ -10,9 +10,6 @@ using namespace Poincare;
 
 namespace Shared {
 
-constexpr char GlobalContext::expExtension[];
-constexpr char GlobalContext::funcExtension[];
-constexpr char GlobalContext::seqExtension[];
 constexpr const char * GlobalContext::k_extensions[];
 
 bool GlobalContext::SymbolAbstractNameIsFree(const char * baseName) {
@@ -23,10 +20,10 @@ Poincare::Expression GlobalContext::ExpressionFromRecord(Ion::Storage::Record re
   if (record.isNull() || record.value().size == 0) {
     return Expression();
   }
-  if (Ion::Storage::FullNameHasExtension(record.fullName(), expExtension, strlen(expExtension))) {
+  if (Ion::Storage::FullNameHasExtension(record.fullName(), Ion::Storage::expExtension, strlen(Ion::Storage::expExtension))) {
     return ExpressionFromSymbolRecord(record);
   }
-  assert(Ion::Storage::FullNameHasExtension(record.fullName(), funcExtension, strlen(funcExtension)));
+  assert(Ion::Storage::FullNameHasExtension(record.fullName(), Ion::Storage::funcExtension, strlen(Ion::Storage::funcExtension)));
   return ExpressionFromFunctionRecord(record);
 }
 
@@ -34,7 +31,7 @@ Poincare::Expression GlobalContext::ExpressionFromSymbolRecord(Ion::Storage::Rec
   if (record.isNull() || record.value().size == 0) {
     return Expression();
   }
-  assert(Ion::Storage::FullNameHasExtension(record.fullName(), expExtension, strlen(expExtension)));
+  assert(Ion::Storage::FullNameHasExtension(record.fullName(), Ion::Storage::expExtension, strlen(Ion::Storage::expExtension)));
   // An expression record value is the expression itself
   Ion::Storage::Record::Data d = record.value();
   return Expression::ExpressionFromAddress(d.buffer, d.size);
@@ -43,7 +40,7 @@ Poincare::Expression GlobalContext::ExpressionFromFunctionRecord(Ion::Storage::R
   if (record.isNull() || record.value().size == 0) {
     return Expression();
   }
-  if (!Ion::Storage::FullNameHasExtension(record.fullName(), funcExtension, strlen(funcExtension))) {
+  if (!Ion::Storage::FullNameHasExtension(record.fullName(), Ion::Storage::funcExtension, strlen(Ion::Storage::funcExtension))) {
     return Expression();
   }
   /* An function record value has metadata before the expression. To get the
@@ -94,7 +91,7 @@ const Expression GlobalContext::ExpressionForSymbolAndRecord(const SymbolAbstrac
 
 const Expression GlobalContext::ExpressionForActualSymbol(const SymbolAbstract & symbol, Ion::Storage::Record r) {
   assert(symbol.type() == ExpressionNode::Type::Symbol);
-  if (r.isNull() || !Ion::Storage::FullNameHasExtension(r.fullName(), expExtension, strlen(expExtension))) {
+  if (r.isNull() || !Ion::Storage::FullNameHasExtension(r.fullName(), Ion::Storage::expExtension, strlen(Ion::Storage::expExtension))) {
     return Expression();
   }
   // Look up the file system for symbol
@@ -102,7 +99,7 @@ const Expression GlobalContext::ExpressionForActualSymbol(const SymbolAbstract &
 }
 
 Ion::Storage::Record::ErrorStatus GlobalContext::SetExpressionForActualSymbol(const Expression & expression, const SymbolAbstract & symbol, Ion::Storage::Record previousRecord) {
-  if (!previousRecord.isNull() && Ion::Storage::FullNameHasExtension(previousRecord.fullName(), funcExtension, strlen(funcExtension))) {
+  if (!previousRecord.isNull() && Ion::Storage::FullNameHasExtension(previousRecord.fullName(), Ion::Storage::funcExtension, strlen(Ion::Storage::funcExtension))) {
     /* A function can overwrite a variable, but a variable cannot be created if
      * it has the same name as an existing function. */
     // TODO Pop up "Name taken for a function"
@@ -110,13 +107,13 @@ Ion::Storage::Record::ErrorStatus GlobalContext::SetExpressionForActualSymbol(co
   }
   // Delete any record with same name (as it is going to be overriden)
   previousRecord.destroy();
-  return Ion::Storage::sharedStorage()->createRecordWithExtension(symbol.name(), expExtension, expression.addressInPool(), expression.size());
+  return Ion::Storage::sharedStorage()->createRecordWithExtension(symbol.name(), Ion::Storage::expExtension, expression.addressInPool(), expression.size());
 }
 
 Ion::Storage::Record::ErrorStatus GlobalContext::SetExpressionForFunctionRecord(Expression expressionToStore, Ion::Storage::Record previousRecord, const char * baseName) {
   Ion::Storage::Record recordToSet = previousRecord;
   Ion::Storage::Record::ErrorStatus error = Ion::Storage::Record::ErrorStatus::None;
-  if (!Ion::Storage::FullNameHasExtension(previousRecord.fullName(), funcExtension, strlen(funcExtension))) {
+  if (!Ion::Storage::FullNameHasExtension(previousRecord.fullName(), Ion::Storage::funcExtension, strlen(Ion::Storage::funcExtension))) {
     // The previous record was not a function. Destroy it and create the new record.
     previousRecord.destroy();
     StorageCartesianFunction newModel = StorageCartesianFunction::NewModel(&error, baseName);
@@ -134,8 +131,7 @@ Ion::Storage::Record::ErrorStatus GlobalContext::SetExpressionForFunction(const
 }
 
 Ion::Storage::Record GlobalContext::SymbolAbstractRecordWithBaseName(const char * name) {
-  const char * extensions[2] = {expExtension, funcExtension/*, seqExtension*/};
-  return Ion::Storage::sharedStorage()->recordBaseNamedWithExtensions(name, extensions, 2);
+  return Ion::Storage::sharedStorage()->recordBaseNamedWithExtensions(name, k_extensions, k_numberOfExtensions);
 }
 
 }
diff --git a/apps/shared/global_context.h b/apps/shared/global_context.h
index 10a0c8d09..617eca3c5 100644
--- a/apps/shared/global_context.h
+++ b/apps/shared/global_context.h
@@ -14,10 +14,7 @@ namespace Shared {
 class GlobalContext final : public Poincare::Context {
 public:
   static constexpr int k_numberOfExtensions = 2;
-  static constexpr char expExtension[] = "exp"; // TODO: store this elsewhere?
-  static constexpr char funcExtension[] = "func"; // TODO: store this elsewhere?
-  static constexpr const char * k_extensions[] = {expExtension, funcExtension};
-  static constexpr char seqExtension[] = "seq";
+  static constexpr const char * k_extensions[] = {Ion::Storage::expExtension, Ion::Storage::funcExtension};
 
   // Storage information
   static bool SymbolAbstractNameIsFree(const char * baseName);
diff --git a/apps/shared/storage_cartesian_function.cpp b/apps/shared/storage_cartesian_function.cpp
index ad76296f0..4ce38c7fe 100644
--- a/apps/shared/storage_cartesian_function.cpp
+++ b/apps/shared/storage_cartesian_function.cpp
@@ -53,7 +53,7 @@ StorageCartesianFunction StorageCartesianFunction::NewModel(Ion::Storage::Record
     DefaultName(nameBuffer, SymbolAbstract::k_maxNameSize);
     baseName = nameBuffer;
   }
-  *error = Ion::Storage::sharedStorage()->createRecordWithExtension(baseName, GlobalContext::funcExtension, &data, sizeof(data));
+  *error = Ion::Storage::sharedStorage()->createRecordWithExtension(baseName, Ion::Storage::funcExtension, &data, sizeof(data));
 
   // Return if error
   if (*error != Ion::Storage::Record::ErrorStatus::None) {
@@ -61,7 +61,7 @@ StorageCartesianFunction StorageCartesianFunction::NewModel(Ion::Storage::Record
   }
 
   // Return the StorageCartesianFunction withthe new record
-  return StorageCartesianFunction(Ion::Storage::sharedStorage()->recordBaseNamedWithExtension(baseName, GlobalContext::funcExtension));
+  return StorageCartesianFunction(Ion::Storage::sharedStorage()->recordBaseNamedWithExtension(baseName, Ion::Storage::funcExtension));
 }
 
 int StorageCartesianFunction::derivativeNameWithArgument(char * buffer, size_t bufferSize, char arg) {
diff --git a/apps/solver/equation.cpp b/apps/solver/equation.cpp
index 7352ba583..52041e04e 100644
--- a/apps/solver/equation.cpp
+++ b/apps/solver/equation.cpp
@@ -12,8 +12,6 @@ using namespace Shared;
 
 namespace Solver {
 
-constexpr char Equation::extension[];
-
 Equation::Equation(Ion::Storage::Record record) :
   SingleExpressionModelHandle(record)
 {
diff --git a/apps/solver/equation.h b/apps/solver/equation.h
index 6db7e8249..65bda4052 100644
--- a/apps/solver/equation.h
+++ b/apps/solver/equation.h
@@ -14,7 +14,6 @@ public:
   Poincare::Expression standardForm(Poincare::Context * context) const { return m_handle.standardForm(this, context); }
   bool containsIComplex(Poincare::Context * context) const;
 
-  static constexpr char extension[] = "eq"; // TODO: store this elsewhere?
 private:
   class Handle : public Shared::ExpressionModelHandle {
   public:
diff --git a/apps/solver/equation_store.cpp b/apps/solver/equation_store.cpp
index 3cbe557bd..be1491cf5 100644
--- a/apps/solver/equation_store.cpp
+++ b/apps/solver/equation_store.cpp
@@ -35,13 +35,13 @@ Ion::Storage::Record::ErrorStatus EquationStore::addEmptyModel() {
   int currentNumber = 0;
   while (currentNumber < k_maxNumberOfEquations) {
     name[1] = '0'+currentNumber;
-    if (Ion::Storage::sharedStorage()->recordBaseNamedWithExtension(name, Equation::extension).isNull()) {
+    if (Ion::Storage::sharedStorage()->recordBaseNamedWithExtension(name, Ion::Storage::eqExtension).isNull()) {
       break;
     }
     currentNumber++;
   }
   assert(currentNumber < k_maxNumberOfEquations);
-  return Ion::Storage::sharedStorage()->createRecordWithExtension(name, Equation::extension, nullptr, 0);
+  return Ion::Storage::sharedStorage()->createRecordWithExtension(name, Ion::Storage::eqExtension, nullptr, 0);
 }
 
 void EquationStore::setMemoizedModelAtIndex(int cacheIndex, Ion::Storage::Record record) const {
diff --git a/apps/solver/equation_store.h b/apps/solver/equation_store.h
index 2d03d4a05..835da0ec2 100644
--- a/apps/solver/equation_store.h
+++ b/apps/solver/equation_store.h
@@ -78,7 +78,7 @@ private:
   static constexpr int k_maxNumberOfEquations = Poincare::Expression::k_maxNumberOfVariables; // Enable the same number of equations as the number of unknown variables
 
   // StorageExpressionModelStore
-  const char * modelExtension() const override { return Equation::extension; }
+  const char * modelExtension() const override { return Ion::Storage::eqExtension; }
   /* We don't really use model memoization as the number of Equation is limited
    * and we keep enough Equations to store them all. */
   void setMemoizedModelAtIndex(int cacheIndex, Ion::Storage::Record record) const override;
diff --git a/apps/variable_box_controller.cpp b/apps/variable_box_controller.cpp
index e27c06a23..086947b52 100644
--- a/apps/variable_box_controller.cpp
+++ b/apps/variable_box_controller.cpp
@@ -77,9 +77,9 @@ int VariableBoxController::numberOfRows() {
     case Page::RootMenu:
       return k_numberOfMenuRows;
     case Page::Expression:
-      return Storage::sharedStorage()->numberOfRecordsWithExtension(GlobalContext::expExtension);
+      return Storage::sharedStorage()->numberOfRecordsWithExtension(Ion::Storage::expExtension);
     case Page::Function:
-      return Storage::sharedStorage()->numberOfRecordsWithExtension(GlobalContext::funcExtension);
+      return Storage::sharedStorage()->numberOfRecordsWithExtension(Ion::Storage::funcExtension);
     default:
       return 0;
   }
@@ -243,7 +243,7 @@ Layout VariableBoxController::expressionLayoutForRecord(Storage::Record record,
 
 const char * VariableBoxController::extension() const {
   assert(m_currentPage != Page::RootMenu);
-  return m_currentPage == Page::Function ? GlobalContext::funcExtension : GlobalContext::expExtension;
+  return m_currentPage == Page::Function ? Ion::Storage::funcExtension : Ion::Storage::expExtension;
 }
 
 Storage::Record VariableBoxController::recordAtIndex(int rowIndex) {
diff --git a/ion/include/ion/storage.h b/ion/include/ion/storage.h
index 26867768c..403c4d186 100644
--- a/ion/include/ion/storage.h
+++ b/ion/include/ion/storage.h
@@ -20,6 +20,11 @@ public:
   static Storage * sharedStorage();
   constexpr static char k_dotChar = '.';
 
+  static constexpr char eqExtension[] = "eq";
+  static constexpr char expExtension[] = "exp";
+  static constexpr char funcExtension[] = "func";
+  static constexpr char seqExtension[] = "seq";
+
   class Record {
     /* A Record is identified by the CRC32 on its fullName because:
      * - A record is identified by its fullName, which is unique
@@ -103,7 +108,7 @@ public:
   Record recordWithExtensionAtIndex(const char * extension, int index);
   Record recordNamed(const char * fullName);
   Record recordBaseNamedWithExtension(const char * baseName, const char * extension);
-  Record recordBaseNamedWithExtensions(const char * baseName, const char * extension[], size_t numberOfExtensions);
+  Record recordBaseNamedWithExtensions(const char * baseName, const char * const extension[], size_t numberOfExtensions);
 
   // Record destruction
   void destroyAllRecords();
diff --git a/ion/src/shared/storage.cpp b/ion/src/shared/storage.cpp
index 7e007851f..0ad38552f 100644
--- a/ion/src/shared/storage.cpp
+++ b/ion/src/shared/storage.cpp
@@ -22,6 +22,11 @@ namespace Ion {
 
 uint32_t staticStorageArea[sizeof(Storage)/sizeof(uint32_t)] = {0};
 
+constexpr char Storage::expExtension[];
+constexpr char Storage::funcExtension[];
+constexpr char Storage::seqExtension[];
+constexpr char Storage::eqExtension[];
+
 Storage * Storage::sharedStorage() {
   static Storage * storage = nullptr;
   if (storage == nullptr) {
@@ -220,7 +225,7 @@ Storage::Record Storage::recordBaseNamedWithExtension(const char * baseName, con
   return recordBaseNamedWithExtensions(baseName, extensions, 1);
 }
 
-Storage::Record Storage::recordBaseNamedWithExtensions(const char * baseName, const char * extensions[], size_t numberOfExtensions) {
+Storage::Record Storage::recordBaseNamedWithExtensions(const char * baseName, const char * const extensions[], size_t numberOfExtensions) {
   size_t nameLength = strlen(baseName);
   for (char * p : *this) {
     const char * currentName = fullNameOfRecordStarting(p);