diff --git a/examples/14_toml_template.cpp b/examples/14_toml_template.cpp
index 5f928322a1..75c97de8d6 100644
--- a/examples/14_toml_template.cpp
+++ b/examples/14_toml_template.cpp
@@ -72,7 +72,7 @@ void write()
      */
     E["z"].resetDataset({});
 
-    ds.extent = {10};
+    ds.extent = std::vector<openPMD::Extent::value_type>{10};
 
     auto electrons = iteration.particles["e"];
     electrons["position"]["x"].resetDataset(ds);
diff --git a/include/openPMD/Iteration.hpp b/include/openPMD/Iteration.hpp
index ef3217bef1..c66199c46f 100644
--- a/include/openPMD/Iteration.hpp
+++ b/include/openPMD/Iteration.hpp
@@ -344,7 +344,7 @@ class Iteration : public Attributable
      */
     struct BeginStepStatus
     {
-        using AvailableIterations_t = std::vector<uint64_t>;
+        using AvailableIterations_t = std::vector<IterationIndex_t>;
 
         AdvanceStatus stepStatus{};
         /*
diff --git a/src/IO/HDF5/HDF5IOHandler.cpp b/src/IO/HDF5/HDF5IOHandler.cpp
index 545fe9c52d..ee02020983 100644
--- a/src/IO/HDF5/HDF5IOHandler.cpp
+++ b/src/IO/HDF5/HDF5IOHandler.cpp
@@ -1582,7 +1582,7 @@ void HDF5IOHandlerImpl::openDataset(
     {
         // Is a scalar. Since the openPMD-api frontend supports no scalar
         // datasets, return the extent as {1}
-        *parameters.extent = {1};
+        *parameters.extent = std::vector<Extent::value_type>{1};
     }
     else
     {
diff --git a/src/Iteration.cpp b/src/Iteration.cpp
index a835d1d3cf..ab35c1e3ae 100644
--- a/src/Iteration.cpp
+++ b/src/Iteration.cpp
@@ -863,7 +863,8 @@ auto Iteration::beginStep(
     else if (thisObject.has_value())
     {
         IterationIndex_t idx = series.indexOf(*thisObject)->first;
-        res.iterationsInOpenedStep = {idx};
+        res.iterationsInOpenedStep =
+            std::vector<Iteration::IterationIndex_t>{idx};
     }
     else
     {
diff --git a/src/snapshots/ContainerImpls.cpp b/src/snapshots/ContainerImpls.cpp
index 7fc04e000a..dd6a2430a9 100644
--- a/src/snapshots/ContainerImpls.cpp
+++ b/src/snapshots/ContainerImpls.cpp
@@ -289,7 +289,8 @@ auto StatefulSnapshotsContainer::operator[](key_type const &key)
             {
             case AdvanceStatus::OK:
                 ++during.step_count;
-                during.available_iterations_in_step = {key};
+                during.available_iterations_in_step =
+                    std::vector<Iteration::IterationIndex_t>{key};
                 break;
             case AdvanceStatus::RANDOMACCESS:
                 during.available_iterations_in_step.emplace_back(key);