From 1c58af48e50390652f1bc4983e8ea16669c3d93d Mon Sep 17 00:00:00 2001
From: Maarten Sebregts <110895564+maarten-ic@users.noreply.github.com>
Date: Tue, 3 Mar 2026 14:48:19 +0100
Subject: [PATCH 01/16] Implement `list_filled_paths` for the HDF5 backend
 (#39)

---
 include/al_backend.h                       | 11 ++++++
 include/al_lowlevel.h                      | 14 +++++++
 python/imas_core/_al_lowlevel.pyx          | 19 ++++++++++
 python/imas_core/al_lowlevel_interface.pxd |  2 +
 src/al_lowlevel.cpp                        | 24 ++++++++++++
 src/ascii_backend.cpp                      |  3 ++
 src/ascii_backend.h                        |  1 +
 src/flexbuffers_backend.cpp                |  9 +++++
 src/flexbuffers_backend.h                  |  1 +
 src/hdf5/hdf5_backend.cpp                  |  8 ++++
 src/hdf5/hdf5_backend.h                    |  1 +
 src/hdf5/hdf5_reader.cpp                   | 43 ++++++++++++++++++++++
 src/hdf5/hdf5_reader.h                     |  1 +
 src/mdsplus/mdsplus_backend.cpp            |  4 ++
 src/mdsplus/mdsplus_backend.h              |  1 +
 src/memory_backend.cpp                     |  5 ++-
 src/memory_backend.h                       |  1 +
 src/no_backend.cpp                         |  8 ++++
 src/no_backend.h                           |  2 +
 src/uda/uda_backend.cpp                    |  3 ++
 src/uda/uda_backend.h                      |  1 +
 21 files changed, 161 insertions(+), 1 deletion(-)

diff --git a/include/al_backend.h b/include/al_backend.h
index afa1cdc8..aec9860f 100644
--- a/include/al_backend.h
+++ b/include/al_backend.h
@@ -175,6 +175,17 @@ class IMAS_CORE_LIBRARY_API Backend
   virtual void get_occurrences(Context* ctx, const char* ids_name, int** occurrences_list, int* size) = 0;
 
 
+  /**
+     Get a list of all Data Dictionary paths for which some data is filled.
+     This function is only implemented for tensorizing backends (i.e. the HDF5 backend).
+     @param[in] dataobjectname IDS name and occurrence
+     @param[in,out] path_list list of c-style strings (ending with a null byte)
+     @param[in,out] size specify the size of the array (number of elements)
+     @throw BackendException
+  */
+  virtual void list_filled_paths(Context* ctx, const char* dataobjectname, char*** path_list, int* size) = 0;
+
+
   /**
     Returns true if the backend performs time data interpolation (e.g time slices operations or IMAS-3885 with data resampling), false otherwise.
   **/
diff --git a/include/al_lowlevel.h b/include/al_lowlevel.h
index e2dea3a2..e3bd79be 100644
--- a/include/al_lowlevel.h
+++ b/include/al_lowlevel.h
@@ -490,6 +490,20 @@ extern "C"
 
   IMAS_CORE_LIBRARY_API al_status_t al_get_occurrences(int pctxID, const char* ids_name, int** occurrences_list, int* size);
 
+  /**
+     Get a list of Data Dictionary paths (without indices) containing filled data in the backend.
+
+     Notes:
+     1. This function is only implemented for tensorizing backends (i.e. the HDF5 backend).
+     2. The paths may appear in any order.
+     3. The caller is responsible for freeing the list and all strings in it.
+
+     @param[in] dataobjectname IDS name and occurrence, e.g. "core_profiles", "equilibrium/1"
+     @param[in,out] path_list list of c-style strings (ending with a null byte)
+     @param[in,out] size specify the size of the array (number of elements)
+   */
+  IMAS_CORE_LIBRARY_API al_status_t al_list_filled_paths(int pctxID, const char* dataobjectname, char*** path_list, int* size);
+
   //IMAS_CORE_LIBRARY_API al_status_t al_close_pulse(int pctxID, int mode, const char *options);
   
   //HLI wrappers for plugins API
diff --git a/python/imas_core/_al_lowlevel.pyx b/python/imas_core/_al_lowlevel.pyx
index 562940d3..5eb16a80 100644
--- a/python/imas_core/_al_lowlevel.pyx
+++ b/python/imas_core/_al_lowlevel.pyx
@@ -1227,3 +1227,22 @@ def al_get_occurrences(ctx, ids_name):
 def get_al_version():
     version = ll.getALVersion()
     return version.decode('UTF-8')
+
+
+def al_list_filled_paths(ctx: int, dataobjectname: str):
+    cdef char** path_list
+    cdef int cSize
+
+    al_status = ll.al_list_filled_paths(ctx, dataobjectname.encode(), &path_list, &cSize)
+    if al_status.code < 0:
+        raise get_proper_exception_class(f'Error while calling al_list_filled_paths: {al_status.message.decode()}', al_status.code)
+
+    # Create python list of strings from the C-style path_list and clean up memory
+    result = []
+    for i in range(cSize):
+        result.append(path_list[i].decode())
+        free(path_list[i])
+    if cSize > 0:
+        free(path_list)
+
+    return al_status.code, result
diff --git a/python/imas_core/al_lowlevel_interface.pxd b/python/imas_core/al_lowlevel_interface.pxd
index b590795e..4ac9c78a 100644
--- a/python/imas_core/al_lowlevel_interface.pxd
+++ b/python/imas_core/al_lowlevel_interface.pxd
@@ -54,4 +54,6 @@ cdef extern from "al_lowlevel.h":
 
     al_status_t al_get_occurrences(int ctx, const char* ids_name, int **occurrences_list, int *size)
 
+    al_status_t al_list_filled_paths(int ctx, const char* dataobjectname, char*** path_list, int *size)
+
     const char* getALVersion()
diff --git a/src/al_lowlevel.cpp b/src/al_lowlevel.cpp
index fa7f42ed..93b80798 100644
--- a/src/al_lowlevel.cpp
+++ b/src/al_lowlevel.cpp
@@ -1775,6 +1775,30 @@ al_status_t al_get_occurrences(int pctxID, const char* ids_name, int** occurrenc
   return status;
 }
 
+al_status_t al_list_filled_paths(int pctxID, const char* dataobjectname, char*** path_list, int* size) {
+  al_status_t status;
+
+  status.code = 0;
+  try {
+    LLenv lle = Lowlevel::getLLenv(pctxID);
+    lle.backend->list_filled_paths(lle.context, dataobjectname, path_list, size);
+  }
+  catch (const ALBackendException& e) {
+    status.code = alerror::backend_err;
+    ALException::registerStatus(status.message, __func__, e);
+  }
+  catch (const ALLowlevelException& e) {
+    status.code = alerror::lowlevel_err;
+    ALException::registerStatus(status.message, __func__, e);
+  }
+  catch (const std::exception& e) {
+    status.code = alerror::unknown_err;
+    ALException::registerStatus(status.message, __func__, e);
+  }
+
+  return status;
+}
+
 
 al_status_t al_setvalue_parameter_plugin(const char* parameter_name, int datatype, int dim, int *size, void *data, const char* pluginName) {
     al_status_t status;
diff --git a/src/ascii_backend.cpp b/src/ascii_backend.cpp
index 40d943ed..2fa9be03 100644
--- a/src/ascii_backend.cpp
+++ b/src/ascii_backend.cpp
@@ -708,4 +708,7 @@ void AsciiBackend::get_occurrences(Context* ctx, const  char* ids_name, int** oc
     (*occurrences_list)[i] = occurrences[i];
 }
 
+void AsciiBackend::list_filled_paths(Context* ctx, const char* dataobjectname, char*** path_list, int* size) {
+    throw ALBackendException("list_filled_paths is not implemented in the ASCII Backend", LOG);
+}
 
diff --git a/src/ascii_backend.h b/src/ascii_backend.h
index fe884e5c..8ccbd26d 100644
--- a/src/ascii_backend.h
+++ b/src/ascii_backend.h
@@ -91,6 +91,7 @@ class IMAS_CORE_LIBRARY_API AsciiBackend : public Backend
   std::pair<int,int> getVersion(DataEntryContext *ctx) override;
 
   void get_occurrences(Context* ctx, const  char* ids_name, int** occurrences_list, int* size) override;
+  void list_filled_paths(Context* ctx, const char* dataobjectname, char*** path_list, int* size) override;
 
   bool supportsTimeDataInterpolation() override {
     return false;
diff --git a/src/flexbuffers_backend.cpp b/src/flexbuffers_backend.cpp
index 32f71811..75494803 100644
--- a/src/flexbuffers_backend.cpp
+++ b/src/flexbuffers_backend.cpp
@@ -398,6 +398,15 @@ void FlexbuffersBackend::get_occurrences(
     throw ALBackendException("get_occurrences is not implemented in the Serialize Backend", LOG);
 }
 
+void FlexbuffersBackend::list_filled_paths(
+    Context* ctx,
+    const char* dataobjectname,
+    char*** path_list,
+    int* size
+) {
+    throw ALBackendException("list_filled_paths is not implemented in the Serialize Backend", LOG);
+}
+
 void FlexbuffersBackend::_start_vector() {
     _vector_starts.push(_builder->StartVector());
 }
diff --git a/src/flexbuffers_backend.h b/src/flexbuffers_backend.h
index 5517cb2e..7471be24 100644
--- a/src/flexbuffers_backend.h
+++ b/src/flexbuffers_backend.h
@@ -48,6 +48,7 @@ class IMAS_CORE_LIBRARY_API FlexbuffersBackend : public Backend
     void deleteData(OperationContext *ctx, std::string path) override;
     void beginArraystructAction(ArraystructContext *ctx, int *size) override;
     void get_occurrences(Context* ctx, const char* ids_name, int** occurrences_list, int* size) override;
+    void list_filled_paths(Context* ctx, const char* dataobjectname, char*** path_list, int* size) override;
     // timerange (get_sample) API is not supported:
     bool supportsTimeDataInterpolation() override { return false; }
     bool supportsTimeRangeOperation() override { return false; }
diff --git a/src/hdf5/hdf5_backend.cpp b/src/hdf5/hdf5_backend.cpp
index 2e4112e7..cb95f539 100644
--- a/src/hdf5/hdf5_backend.cpp
+++ b/src/hdf5/hdf5_backend.cpp
@@ -162,3 +162,11 @@ void HDF5Backend::get_occurrences(Context* ctx, const  char* ids_name, int** occ
         throw ALBackendException("HDF5Backend: master file not opened while calling HDF5Backend::get_occurrences()", LOG); 
     hdf5Reader->get_occurrences(ids_name, occurrences_list, size, file_id);
 }
+
+void HDF5Backend::list_filled_paths(Context* ctx, const char* dataobjectname, char*** path_list, int* size)
+{
+    if (file_id == -1) // master file not opened
+        throw ALBackendException("HDF5Backend: master file not opened while calling HDF5Backend::list_filled_paths()", LOG); 
+
+    hdf5Reader->list_filled_paths(dataobjectname, path_list, size, file_id, opened_IDS_files, files_directory, relative_file_path);
+}
diff --git a/src/hdf5/hdf5_backend.h b/src/hdf5/hdf5_backend.h
index 26bdc001..96cc1e60 100644
--- a/src/hdf5/hdf5_backend.h
+++ b/src/hdf5/hdf5_backend.h
@@ -131,6 +131,7 @@ class HDF5Backend:public Backend {
     void beginAction(OperationContext * ctx) override;
 
     void get_occurrences(Context* ctx, const char* ids_name, int** occurrences_list, int* size) override;
+    void list_filled_paths(Context* ctx, const char* dataobjectname, char*** path_list, int* size) override;
 
     bool supportsTimeDataInterpolation() override {
       return true;
diff --git a/src/hdf5/hdf5_reader.cpp b/src/hdf5/hdf5_reader.cpp
index 4dde86c7..04dcd7e0 100644
--- a/src/hdf5/hdf5_reader.cpp
+++ b/src/hdf5/hdf5_reader.cpp
@@ -1568,6 +1568,49 @@ void HDF5Reader::get_occurrences(const char *ids_name, int **occurrences_list, i
         p[i] = occurrences[i];
 }
 
+void HDF5Reader::list_filled_paths(const char* dataobjectname, char*** path_list, int* size, hid_t file_id, std::unordered_map < std::string, hid_t > &opened_IDS_files, std::string & files_directory, std::string & relative_file_path)
+{
+    HDF5Utils hdf5_utils;
+    // Create temporary OperationContext to allow reusing existing logic from hdf5_utils:
+    OperationContext ctx(NULL, dataobjectname, "", READ_OP);
+    hid_t gid = -1;
+    hdf5_utils.open_IDS_group(&ctx, file_id, opened_IDS_files, files_directory, relative_file_path, &gid);
+    if (gid <= 0) {
+        // Group does not exist => nothing is filled
+        *size = 0;
+        return;
+    }
+
+    // Create a vector of all link names in the hdf5 group
+    std::vector<std::string> variables;
+    H5L_iterate_t iterate_callback = [](hid_t group_id, const char* cname, const H5L_info_t* info, void* op_data) -> herr_t {
+        std::string name(cname);
+        // Skip if name ends with _SHAPE
+        if (name.size() < 6 || name.substr(name.size() - 6) != "_SHAPE")
+            static_cast<std::vector<std::string>*>(op_data)->push_back(name);
+        return 0; // success
+    };
+    herr_t status = H5Literate(gid, H5_INDEX_NAME, H5_ITER_NATIVE, NULL, iterate_callback, &variables);
+    if (status != 0)
+        throw ALBackendException("HDF5Backend: H5Literate has failed in HDF5Reader::list_filled_paths()", LOG);
+
+    // Convert to DD path: remove AoS brackets ([]) and use / to separate paths
+    for (auto &str : variables) {
+        // Remove square brackets
+        str.erase(std::remove(str.begin(), str.end(), '['), str.end());
+        str.erase(std::remove(str.begin(), str.end(), ']'), str.end());
+        // Replace '&' with '/'
+        std::replace(str.begin(), str.end(), '&', '/');
+    }
+
+    // Create the C-style array:
+    *size = variables.size();
+    *path_list = (char**) malloc(*size * sizeof(char*));
+    for (int i=0; i < *size; ++i) {
+        (*path_list)[i] = strdup(variables[i].c_str());
+    }
+}
+
 herr_t HDF5Reader::iterate_callback(hid_t loc_id, const char *name, const H5L_info_t *info, void *callback_data)
 {
     std::vector<std::string> *op = reinterpret_cast<std::vector<std::string> *>(callback_data);
diff --git a/src/hdf5/hdf5_reader.h b/src/hdf5/hdf5_reader.h
index 80ebeaba..a00874cd 100644
--- a/src/hdf5/hdf5_reader.h
+++ b/src/hdf5/hdf5_reader.h
@@ -89,6 +89,7 @@ class HDF5Reader {
     virtual int read_ND_Data(Context * ctx, std::string & att_name, std::string & timebasename, int datatype, void **data, int *dim, int *size);
     virtual void beginReadArraystructAction(ArraystructContext * ctx, int *size);
     virtual void get_occurrences(const char* ids_name, int** occurrences_list, int* size, hid_t master_file_id);
+    void list_filled_paths(const char* dataobjectname, char*** path_list, int* size, hid_t file_id, std::unordered_map < std::string, hid_t > &opened_IDS_files, std::string & files_directory, std::string & relative_file_path);
 
     void open_IDS_group(OperationContext * ctx, hid_t file_id, std::unordered_map < std::string, hid_t > &opened_IDS_files, std::string & files_directory, std::string & relative_file_path);
     void close_file_handler(std::string external_link_name, std::unordered_map < std::string, hid_t > &opened_IDS_files);
diff --git a/src/mdsplus/mdsplus_backend.cpp b/src/mdsplus/mdsplus_backend.cpp
index a0c73f1b..a8fe928a 100644
--- a/src/mdsplus/mdsplus_backend.cpp
+++ b/src/mdsplus/mdsplus_backend.cpp
@@ -4932,6 +4932,10 @@ void MDSplusBackend::get_occurrences(Context* ctx, const char* ids_name, int** o
 	*size = occurrences.size();
 }
 
+void MDSplusBackend::list_filled_paths(Context* ctx, const char* dataobjectname, char*** path_list, int* size) {
+    throw ALBackendException("list_filled_paths is not implemented in the MDSplus Backend", LOG);
+}
+
  void MDSplusBackend::fullPath(Context *ctx, std::string &path) {
    if (ctx->getType() == CTX_PULSE_TYPE) {
        path = "";
diff --git a/src/mdsplus/mdsplus_backend.h b/src/mdsplus/mdsplus_backend.h
index 75617518..a9dcb524 100644
--- a/src/mdsplus/mdsplus_backend.h
+++ b/src/mdsplus/mdsplus_backend.h
@@ -250,6 +250,7 @@ class IMAS_CORE_LIBRARY_API MDSplusBackend:public Backend
     std::pair<int,int> getVersion(DataEntryContext *ctx) override;
 
     void get_occurrences(Context* ctx, const char* ids_name, int** occurrences_list, int* size) override;
+    void list_filled_paths(Context* ctx, const char* dataobjectname, char*** path_list, int* size) override;
 
     bool supportsTimeDataInterpolation() {
       return true;
diff --git a/src/memory_backend.cpp b/src/memory_backend.cpp
index 9b380fb3..8009d20e 100644
--- a/src/memory_backend.cpp
+++ b/src/memory_backend.cpp
@@ -1148,7 +1148,10 @@ else
 		throw ALBackendException(message, LOG);
 	}
 
-
+	void MemoryBackend::list_filled_paths(Context* ctx, const char* dataobjectname, char*** path_list, int* size) {
+		std::string message("list_filled_paths() is not implemented in the MemoryBackend");
+		throw ALBackendException(message, LOG);
+	}
 
 //////////////////////////////////////////////////////////////////////////
 
diff --git a/src/memory_backend.h b/src/memory_backend.h
index e74bcb92..c0d22ec9 100644
--- a/src/memory_backend.h
+++ b/src/memory_backend.h
@@ -673,6 +673,7 @@ class IMAS_CORE_LIBRARY_API MemoryBackend:public Backend
     ALData *getAlSlice(ArraystructContext *ctx, ALData &inData, double time, std::vector<double> timebaseV);
 
 	void get_occurrences(Context* ctx, const char* ids_name, int** occurrences_list, int* size) override;
+    void list_filled_paths(Context* ctx, const char* dataobjectname, char*** path_list, int* size) override;
 
 	bool supportsTimeDataInterpolation() override {
       return false;
diff --git a/src/no_backend.cpp b/src/no_backend.cpp
index 2b3807cb..222f21c2 100644
--- a/src/no_backend.cpp
+++ b/src/no_backend.cpp
@@ -85,3 +85,11 @@ void NoBackend::get_occurrences(Context* ctx, const char* ids_name, int** occurr
     *size = 0;
 }
 
+void NoBackend::list_filled_paths(Context* ctx, const char* dataobjectname, char*** path_list, int* size)
+{
+  if (verbose) {
+      std::string message("list_filled_paths() is not implemented in the NoBackend");
+      throw ALBackendException(message, LOG);
+  }
+  *size = 0;
+}
diff --git a/src/no_backend.h b/src/no_backend.h
index 8b46e6b2..2162632a 100644
--- a/src/no_backend.h
+++ b/src/no_backend.h
@@ -64,6 +64,8 @@ class IMAS_CORE_LIBRARY_API NoBackend : public Backend
 
   void get_occurrences(Context* ctx, const  char* ids_name, int** occurrences_list, int* size) override;
 
+  void list_filled_paths(Context* ctx, const char* dataobjectname, char*** path_list, int* size) override;
+
   bool supportsTimeDataInterpolation() override {
       return false;
     }
diff --git a/src/uda/uda_backend.cpp b/src/uda/uda_backend.cpp
index b1ccb81b..74a538b3 100644
--- a/src/uda/uda_backend.cpp
+++ b/src/uda/uda_backend.cpp
@@ -1310,3 +1310,6 @@ void UDABackend::get_occurrences(Context* ctx, const char* ids_name, int** occur
     }
 }
 
+void UDABackend::list_filled_paths(Context* ctx, const char* dataobjectname, char*** path_list, int* size) {
+    throw ALBackendException("list_filled_paths is not implemented in the UDA Backend", LOG);
+}
diff --git a/src/uda/uda_backend.h b/src/uda/uda_backend.h
index 0869aa3c..115e8d5b 100644
--- a/src/uda/uda_backend.h
+++ b/src/uda/uda_backend.h
@@ -183,6 +183,7 @@ class IMAS_CORE_LIBRARY_API UDABackend : public Backend
     std::pair<int,int> getVersion(DataEntryContext *ctx) override;
 
     void get_occurrences(Context* ctx, const char* ids_name, int** occurrences_list, int* size) override;
+    void list_filled_paths(Context* ctx, const char* dataobjectname, char*** path_list, int* size) override;
 
     bool supportsTimeDataInterpolation() override;
 

From a3847742a59da52a735eab83c95feef121884089 Mon Sep 17 00:00:00 2001
From: Paulo Abreu <paulotex@gmx.net>
Date: Mon, 30 Mar 2026 16:41:07 +0200
Subject: [PATCH 02/16] Feature/macos arm (#44)

* Adding UDA support for macOS

* Improving macos detection in CMake, adding arm achitecture
---
 .github/workflows/wheels.yml | 25 +++++++++++++++----------
 CMakeLists.txt               |  5 +----
 pyproject.toml               |  9 +++++++--
 3 files changed, 23 insertions(+), 16 deletions(-)

diff --git a/.github/workflows/wheels.yml b/.github/workflows/wheels.yml
index 4430d290..24bda5f5 100644
--- a/.github/workflows/wheels.yml
+++ b/.github/workflows/wheels.yml
@@ -86,7 +86,7 @@ jobs:
             cibw_archs: arm64
             AL_BACKEND_HDF5: AL_BACKEND_HDF5=ON
             AL_BACKEND_MDSPLUS: AL_BACKEND_MDSPLUS=OFF
-            AL_BACKEND_UDA: AL_BACKEND_UDA=OFF
+            AL_BACKEND_UDA: AL_BACKEND_UDA=ON
             UDA_REF: "2.9.3"
 
           - os: macos-14
@@ -97,7 +97,7 @@ jobs:
             cibw_archs: arm64
             AL_BACKEND_HDF5: AL_BACKEND_HDF5=ON
             AL_BACKEND_MDSPLUS: AL_BACKEND_MDSPLUS=OFF
-            AL_BACKEND_UDA: AL_BACKEND_UDA=OFF
+            AL_BACKEND_UDA: AL_BACKEND_UDA=ON
             UDA_REF: "2.9.3"
         
           - os: macos-14
@@ -108,7 +108,7 @@ jobs:
             cibw_archs: arm64
             AL_BACKEND_HDF5: AL_BACKEND_HDF5=ON
             AL_BACKEND_MDSPLUS: AL_BACKEND_MDSPLUS=OFF
-            AL_BACKEND_UDA: AL_BACKEND_UDA=OFF
+            AL_BACKEND_UDA: AL_BACKEND_UDA=ON
             UDA_REF: "2.9.3"
     
           - os: macos-14
@@ -119,7 +119,7 @@ jobs:
             cibw_archs: arm64
             AL_BACKEND_HDF5: AL_BACKEND_HDF5=ON
             AL_BACKEND_MDSPLUS: AL_BACKEND_MDSPLUS=OFF
-            AL_BACKEND_UDA: AL_BACKEND_UDA=OFF
+            AL_BACKEND_UDA: AL_BACKEND_UDA=ON
             UDA_REF: "2.9.3"
     
           - os: macos-14
@@ -130,7 +130,7 @@ jobs:
             cibw_archs: arm64
             AL_BACKEND_HDF5: AL_BACKEND_HDF5=ON
             AL_BACKEND_MDSPLUS: AL_BACKEND_MDSPLUS=OFF
-            AL_BACKEND_UDA: AL_BACKEND_UDA=OFF
+            AL_BACKEND_UDA: AL_BACKEND_UDA=ON
             UDA_REF: "2.9.3"
     
           - os: windows-2022
@@ -347,10 +347,15 @@ jobs:
             cmake.define.${{ matrix.AL_BACKEND_MDSPLUS }}
             cmake.define.${{ matrix.AL_BACKEND_UDA }}
 
-          # Dependency installationinto /tmp
+          # Dependency installation into /tmp/imas-core-install
           CIBW_BEFORE_ALL_MACOS: >
             brew update >&2;
-            brew install cmake pkg-config boost hdf5 libomp ninja fmt spdlog libxml2 openssl capnp libmemcached >&2;
+            brew install cmake pkg-config boost hdf5 libomp ninja fmt spdlog libxml2 openssl libmemcached >&2;
+            git clone -b master https://github.com/capnproto/capnproto.git >&2 &&
+            cd capnproto >&2;
+            cmake -B build . \
+                -DCMAKE_INSTALL_PREFIX=/tmp/imas-core-install >&2 &&
+            cmake --build build --target install -j >&2;
             git clone --depth 1 --branch ${{ matrix.UDA_REF }} https://github.com/ukaea/UDA.git >&2 &&
             cd UDA >&2;
             cmake -G Ninja -B build . \
@@ -359,14 +364,14 @@ jobs:
                 -DCLIENT_ONLY=ON \
                 -DENABLE_CAPNP=ON \
                 -DMACOSX_DEPLOYMENT_TARGET=14.0 \
-                -DCMAKE_INSTALL_PREFIX=/tmp/uda-install >&2 &&
+                -DCMAKE_INSTALL_PREFIX=/tmp/imas-core-install >&2 &&
             cmake --build build --target install -j >&2;
 
           # Where to find the dependencies
           CIBW_ENVIRONMENT_MACOS: >
             MACOSX_DEPLOYMENT_TARGET=14.0
-            CMAKE_PREFIX_PATH="/tmp/uda-install:/opt/homebrew:/usr/local"
-            PKG_CONFIG_PATH="/tmp/uda-install/lib/pkgconfig:/opt/homebrew/lib/pkgconfig:/usr/local/lib/pkgconfig"
+            CMAKE_PREFIX_PATH="/tmp/imas-core-install:/opt/homebrew:/usr/local"
+            PKG_CONFIG_PATH="/tmp/imas-core-install/lib/pkgconfig:/opt/homebrew/lib/pkgconfig:/usr/local/lib/pkgconfig"
 
         with:
           package-dir: .
diff --git a/CMakeLists.txt b/CMakeLists.txt
index e35f6e6e..a7eb46a0 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -73,13 +73,10 @@ if(NOT PROJECT_VERSION_TWEAK EQUAL 0)
   message("Building a development version of the Access Layer core")
 endif()
 
-if(APPLE)
+if(APPLE AND CMAKE_OSX_ARCHITECTURES MATCHES "arm64")
   # Disable MDSPlus:
   message(STATUS "Disabling MDSPlus backend on macOS")
   set(AL_BACKEND_MDSPLUS OFF CACHE BOOL "MDSPlus backend" FORCE)    
-  # Disable UDA:
-  message(STATUS "Disabling UDA backend on macOS")
-  set(AL_BACKEND_UDA OFF CACHE BOOL "UDA backend" FORCE)    
 endif()
 
 
diff --git a/pyproject.toml b/pyproject.toml
index 9a6d0ee5..e0ce230c 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -62,9 +62,14 @@ before-build = "bash ./ci/wheels/cibw_before_build_win.sh"
 repair-wheel-command = "bash ./ci/wheels/repair_windows.sh {wheel} {dest_dir}"
 
 [tool.cibuildwheel.macos.environment]
-CMAKE_PREFIX_PATH = "/opt/homebrew;/usr/local"
-PKG_CONFIG_PATH = "/opt/homebrew/lib/pkgconfig:/usr/local/lib/pkgconfig"
+CMAKE_PREFIX_PATH = "/tmp/imas-core-install:/opt/homebrew:/usr/local"
+PKG_CONFIG_PATH = "/tmp/imas-core-install/lib/pkgconfig:/opt/homebrew/lib/pkgconfig:/usr/local/lib/pkgconfig"
 MACOSX_DEPLOYMENT_TARGET = "14.0"
+AL_BACKEND_HDF5 = { env = "AL_BACKEND_HDF5", default = "ON" }
+AL_BACKEND_UDA = { env = "AL_BACKEND_UDA", default = "ON" }
+AL_BACKEND_MDSPLUS = { env = "AL_BACKEND_MDSPLUS", default = "OFF" }
+AL_BUILD_MDSPLUS_MODELS = { env = "AL_BUILD_MDSPLUS_MODELS", default = "OFF" }
+AL_PYTHON_BINDINGS = "ON"
 
 [tool.cibuildwheel.macos]
 archs = ["arm64"]

From 087d32c464138a32dc6e34c38cdd2964f9bdb0fd Mon Sep 17 00:00:00 2001
From: Deepak <56668629+deepakmaroo@users.noreply.github.com>
Date: Thu, 9 Apr 2026 09:19:27 +0200
Subject: [PATCH 03/16] Integrated UDA-Plugins api listFilledPaths (#41)

---
 include/al_utilities.h   |  24 +++++++++
 src/CMakeLists.txt       |   1 +
 src/al_utilities.cpp     |  21 ++++++++
 src/hdf5/hdf5_reader.cpp |   7 +--
 src/uda/uda_backend.cpp  | 113 ++++++++++++++++++++++++++++++++++++++-
 5 files changed, 160 insertions(+), 6 deletions(-)
 create mode 100644 include/al_utilities.h
 create mode 100644 src/al_utilities.cpp

diff --git a/include/al_utilities.h b/include/al_utilities.h
new file mode 100644
index 00000000..ed17a4f5
--- /dev/null
+++ b/include/al_utilities.h
@@ -0,0 +1,24 @@
+#ifndef AL_UTILITIES_H
+#define AL_UTILITIES_H
+
+/**
+ * General-purpose utility functions for the Access Layer.
+*/
+
+#include <vector>
+#include <string>
+
+namespace utilities {
+
+/**
+ * Convert a vector of strings into a C-style array of strings.
+ *
+ * @param paths the vector of strings to convert
+ * @param path_list a pointer to the C-style array to create
+ * @param size a pointer to an integer to store the size of the created array
+ */
+void copy_stringvector_to_c_list(const std::vector<std::string>& paths, char*** path_list, int* size);
+
+} // namespace utilities
+
+#endif // AL_UTILITIES_H
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 2800528e..3aa7a997 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -6,6 +6,7 @@ target_sources( al PRIVATE
     al_context.cpp
     al_const.cpp
     al_exception.cpp
+    al_utilities.cpp
     no_backend.cpp
     memory_backend.cpp
     ascii_backend.cpp
diff --git a/src/al_utilities.cpp b/src/al_utilities.cpp
new file mode 100644
index 00000000..f2faa4c7
--- /dev/null
+++ b/src/al_utilities.cpp
@@ -0,0 +1,21 @@
+#include "al_utilities.h"
+
+#include <cstdlib>
+#include <cstring>
+
+namespace utilities {
+
+void copy_stringvector_to_c_list(const std::vector<std::string>& paths, char*** path_list, int* size) {
+    *size = static_cast<int>(paths.size());
+    
+    if (*size == 0) {
+        *path_list = nullptr;
+        return;
+    }
+    
+    *path_list = static_cast<char**>(malloc(*size * sizeof(char*)));
+    for (int i = 0; i < *size; ++i) {
+        (*path_list)[i] = strdup(paths[i].c_str());
+    }
+}
+} // namespace utilities
\ No newline at end of file
diff --git a/src/hdf5/hdf5_reader.cpp b/src/hdf5/hdf5_reader.cpp
index 04dcd7e0..a4a553b9 100644
--- a/src/hdf5/hdf5_reader.cpp
+++ b/src/hdf5/hdf5_reader.cpp
@@ -8,6 +8,7 @@
 #include <stdlib.h>
 #include <limits>
 #include <boost/algorithm/string.hpp>
+#include "al_utilities.h"
 
 #define MAX_LENGTH 200
 #define HOMOGENEOUS_TIME_FIELD_NAME "ids_properties&homogeneous_time"
@@ -1604,11 +1605,7 @@ void HDF5Reader::list_filled_paths(const char* dataobjectname, char*** path_list
     }
 
     // Create the C-style array:
-    *size = variables.size();
-    *path_list = (char**) malloc(*size * sizeof(char*));
-    for (int i=0; i < *size; ++i) {
-        (*path_list)[i] = strdup(variables[i].c_str());
-    }
+    utilities::copy_stringvector_to_c_list(variables, path_list, size);
 }
 
 herr_t HDF5Reader::iterate_callback(hid_t loc_id, const char *name, const H5L_info_t *info, void *callback_data)
diff --git a/src/uda/uda_backend.cpp b/src/uda/uda_backend.cpp
index 74a538b3..d380251e 100644
--- a/src/uda/uda_backend.cpp
+++ b/src/uda/uda_backend.cpp
@@ -17,6 +17,7 @@
 
 #include <string>
 #include <random>
+#include "al_utilities.h"
 
 using namespace semver::literals;
 
@@ -1258,6 +1259,54 @@ std::vector<int> read_occurrences(NodeReader *node) {
     return occurrences;
 }
 
+std::vector<std::string> read_filled_paths(NodeReader *node) {
+    std::vector<std::string> paths;
+
+    // Read the shape
+    std::vector<size_t> shape_vec(1);
+    uda_capnp_read_shape(node, shape_vec.data());
+    const size_t total_bytes = std::accumulate(shape_vec.begin(), shape_vec.end(), 1, std::multiplies<size_t>());
+
+    // For empty buffers, return empty list
+    if (total_bytes == 0) {
+        return paths;
+    }
+
+    const char *name = uda_capnp_read_name(node);
+    if (name != nullptr && std::string(name) != "filled_paths") {
+        throw imas::uda::CacheException("Invalid node: " + std::string(name));
+    }
+
+    bool eos = uda_capnp_read_is_eos(node);
+    if (!eos) {
+        throw imas::uda::CacheException("UDA backend does not currently handle streamed data");
+    }
+
+    size_t num_slices = uda_capnp_read_num_slices(node);
+    if (num_slices != 1) {
+        throw imas::uda::CacheException("Incorrect number of slices for filled_paths node");
+    }
+
+    // Read the data slice
+    size_t slice_size = uda_capnp_read_slice_size(node, 0);
+    if (slice_size != total_bytes) {
+        throw imas::uda::CacheException("Slice size does not match total bytes for filled_paths");
+    }
+
+    std::vector<char> buffer(total_bytes);
+    uda_capnp_read_data(node, 0, buffer.data());
+
+    const char* ptr = buffer.data();
+    const char* end = ptr + total_bytes;
+
+    while (ptr < end && *ptr != '\0') {
+        std::string path(ptr);
+        paths.push_back(path);
+        ptr += strlen(ptr) + 1;
+    }
+
+    return paths;
+}
 } // anon namespace
 
 void UDABackend::get_occurrences(Context* ctx, const char* ids_name, int** occurrences_list, int* size) {
@@ -1311,5 +1360,67 @@ void UDABackend::get_occurrences(Context* ctx, const char* ids_name, int** occur
 }
 
 void UDABackend::list_filled_paths(Context* ctx, const char* dataobjectname, char*** path_list, int* size) {
-    throw ALBackendException("list_filled_paths is not implemented in the UDA Backend", LOG);
+
+    *size = 0;
+    *path_list = nullptr;
+
+    if (access_local_) {
+        return local_backend_->list_filled_paths(ctx, dataobjectname, path_list, size);
+    }
+
+    if (verbose_) {
+        std::cout << "UDABackend list_filled_paths\n";
+    }
+
+    auto query = ctx->getURI().query;
+    std::string backend = get_backend(query);
+    if (backend != "hdf5") {
+        throw ALException("UDABackend only supports HDF5 backend for list_filled_paths API", LOG);
+    }
+    
+    query.remove("backend");
+    query.remove("cache_mode");
+    query.remove("verbose");
+    std::string dd_version = query.get("dd_version").value_or(dd_version_);
+    query.set("dd_version", dd_version);
+    std::string uri = "imas:" + backend + "?" + query.to_string();
+
+    std::stringstream ss;
+
+    ss << plugin_
+       << "::listFilledPaths("
+       << "uri='" << uri << "'"
+       << ", ids='" << dataobjectname << "'"
+       << ")";
+
+    const std::string directive = ss.str();
+
+    if (verbose_) {
+        std::cout << "UDABackend request: " << directive << "\n";
+    }
+
+    try {
+        const uda::Result& result = uda_client_.get(directive, "");
+        
+        if (result.errorCode() == 0 && result.uda_type() == UDA_TYPE_CAPNP) {
+            const char* data = result.raw_data();
+            const size_t result_size = result.size();
+            
+            // If buffer is empty, return empty path list
+            if (result_size == 0) {
+                return;
+            }
+            
+            const auto tree = uda_capnp_deserialise(data, result_size);
+            const auto root = uda_capnp_read_root(tree);
+
+            auto paths = read_filled_paths(root);
+            // Allocate and copy paths to C list
+            utilities::copy_stringvector_to_c_list(paths, path_list, size);
+
+            uda_capnp_free_tree_reader(tree);
+        }
+    } catch (const uda::UDAException& ex) {
+        throw ALException(ex.what(), LOG);
+    }
 }

From 177368f8cb9014686ae036a3744e12f6fe2470d5 Mon Sep 17 00:00:00 2001
From: Prasad <prasad.sawantdesai@gmail.com>
Date: Thu, 9 Apr 2026 17:38:20 +0200
Subject: [PATCH 04/16] fix(hdf5): read HDF5_BACKEND_VERSION using actual
 stored type(#42) (#43)

---
 src/hdf5/hdf5_utils.cpp | 36 +++++++++++++++++++++++-------------
 1 file changed, 23 insertions(+), 13 deletions(-)

diff --git a/src/hdf5/hdf5_utils.cpp b/src/hdf5/hdf5_utils.cpp
index c76352a9..f945ce62 100644
--- a/src/hdf5/hdf5_utils.cpp
+++ b/src/hdf5/hdf5_utils.cpp
@@ -6,6 +6,7 @@
 #include <iostream>
 #include <fstream>
 #include <errno.h>
+#include <vector>
 #include <boost/filesystem.hpp>
 
 using namespace boost::filesystem;
@@ -75,24 +76,33 @@ int
             throw ALBackendException(error_message, LOG);
         }
 
-        hid_t dtype_id = H5Tcopy (H5T_C_S1);
-        H5Tset_size(dtype_id, strlen(backend_version_attribute_name));
-        
-        herr_t tset = H5Tset_cset(dtype_id, H5T_CSET_UTF8);
-        if (tset < 0) {
-            char error_message[100];
-            sprintf(error_message, "Unable to set characters to UTF8 for: %s\n", backend_version_attribute_name);
-            throw ALBackendException(error_message);
+        hid_t attr_file_type = H5Aget_type(att_id);
+        if (attr_file_type < 0) {
+            H5Aclose(att_id);
+            char error_message[200];
+            sprintf(error_message, "Unable to get type of attribute: %s\n", backend_version_attribute_name);
+            throw ALBackendException(error_message, LOG);
         }
+        size_t attr_size = H5Tget_size(attr_file_type);
+        H5T_cset_t attr_cset = H5Tget_cset(attr_file_type);
+        H5Tclose(attr_file_type);
+
+        hid_t dtype_id = H5Tcopy(H5T_C_S1);
+        H5Tset_size(dtype_id, attr_size + 1);
+        H5Tset_strpad(dtype_id, H5T_STR_NULLTERM);
+        H5Tset_cset(dtype_id, attr_cset);
 
-        char version[10];
-        herr_t status = H5Aread(att_id, dtype_id, version);
+        std::string version(attr_size + 1, '\0');
+        herr_t status = H5Aread(att_id, dtype_id, version.data());
         if (status < 0) {
+            H5Tclose(dtype_id);
+            H5Aclose(att_id);
             char error_message[200];
             sprintf(error_message, "Unable to read attribute: %s\n", backend_version_attribute_name);
             throw ALBackendException(error_message, LOG);
         }
-        backend_version = std::string(version);
+        version[attr_size] = '\0';
+        backend_version = version.c_str();
         H5Tclose(dtype_id);
         H5Aclose(att_id);
     } else {
@@ -344,8 +354,8 @@ void HDF5Utils::writeHeader(DataEntryContext * ctx, hid_t file_id, std::string &
 
     //write version to file
     hid_t dataspace_id = H5Screate(H5S_SCALAR);
-    hid_t dtype_id = H5Tcopy (H5T_C_S1);
-    H5Tset_size(dtype_id, strlen(backend_version_attribute_name));
+    hid_t dtype_id = H5Tcopy(H5T_C_S1);
+    H5Tset_size(dtype_id, backend_version.length() + 1);
     herr_t tset = H5Tset_cset(dtype_id, H5T_CSET_UTF8);
     if (tset < 0) {
         char error_message[200];

From 1fb57ecc6a84d7bc9678c6448b5d8af2b224d607 Mon Sep 17 00:00:00 2001
From: prasad-sawantdesai <prasad.sawantdesai@gmail.com>
Date: Tue, 14 Apr 2026 11:16:35 +0200
Subject: [PATCH 05/16] show meaningfull error message when MDSPLUS_MODELS_PATH
 is not set

---
 src/mdsplus/mdsplus_backend.cpp | 25 +++++++++++++++++++++++--
 1 file changed, 23 insertions(+), 2 deletions(-)

diff --git a/src/mdsplus/mdsplus_backend.cpp b/src/mdsplus/mdsplus_backend.cpp
index a8fe928a..fa1fa713 100644
--- a/src/mdsplus/mdsplus_backend.cpp
+++ b/src/mdsplus/mdsplus_backend.cpp
@@ -4496,7 +4496,12 @@ std::string MDSplusBackend::getTimedNode(ArraystructContext *ctx, std::string fu
 	      } catch(MDSplus::MdsException &exc) {
 		if (mode!=alconst::force_open_pulse) {
 		  resetIdsPath(szTree);
-		  throw  ALBackendException(exc.what()+mdsplusBaseStr,LOG);
+		  std::string hint;
+		  const char *modelsPath = getenv("MDSPLUS_MODELS_PATH");
+		  if (!modelsPath || !*modelsPath) {
+		    hint = " -- MDSPLUS_MODELS_PATH is not set; set it to the MDSplus models directory (e.g. export MDSPLUS_MODELS_PATH=/path/to/models/mdsplus)";
+		  }
+		  throw  ALBackendException(exc.what()+mdsplusBaseStr+hint,LOG);
 		}
 	      }
 	  case alconst::create_pulse:
@@ -4509,6 +4514,17 @@ std::string MDSplusBackend::getTimedNode(ArraystructContext *ctx, std::string fu
 	    } catch (const std::exception& exc) {
 	      throw ALBackendException("Unable to create data-entry directory: "+mdsplusBaseStr,LOG);
 	    }
+	    {
+	      const char *modelsPath = getenv("MDSPLUS_MODELS_PATH");
+	      if (!modelsPath || !*modelsPath) {
+	        resetIdsPath(szTree);
+	        throw ALBackendException(
+	          std::string("MDSPLUS_MODELS_PATH is not set. Set it to the MDSplus models directory "
+	          "(e.g. export MDSPLUS_MODELS_PATH=/path/to/models/mdsplus) "
+	          "before creating a pulse file."),
+	          LOG);
+	      }
+	    }
 	    try {
 	      MDSplus::Tree *modelTree = new MDSplus::Tree(szTree, -1, DEF_READONLYMODE);
 	      modelTree->createPulse(shotNum);
@@ -4517,7 +4533,12 @@ std::string MDSplusBackend::getTimedNode(ArraystructContext *ctx, std::string fu
 	      saveVersion(tree);
 	    } catch(MDSplus::MdsException &exc) {
 	      resetIdsPath(szTree);
-	      throw ALBackendException(exc.what()+mdsplusBaseStr,LOG);
+	      std::string hint;
+	      const char *modelsPath = getenv("MDSPLUS_MODELS_PATH");
+	      if (!modelsPath || !*modelsPath) {
+	        hint = " -- MDSPLUS_MODELS_PATH is not set; set it to the MDSplus models directory (e.g. export MDSPLUS_MODELS_PATH=/path/to/models/mdsplus)";
+	      }
+	      throw ALBackendException(exc.what()+mdsplusBaseStr+hint,LOG);
 	    }
 	    break;
 	  default:

From 1784dc64acb66607153bb163c16c5c03007ce30b Mon Sep 17 00:00:00 2001
From: marood <deepakkumar.maroo@iter.org>
Date: Thu, 9 Apr 2026 20:36:37 +0200
Subject: [PATCH 06/16] Added optional argument mode in getOccurrences and
 listFilledPaths UDA-Plugins apis. Effectin when using small UDA_TIMEOUT

---
 src/uda/uda_backend.cpp | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/uda/uda_backend.cpp b/src/uda/uda_backend.cpp
index d380251e..1bb0a868 100644
--- a/src/uda/uda_backend.cpp
+++ b/src/uda/uda_backend.cpp
@@ -1332,6 +1332,7 @@ void UDABackend::get_occurrences(Context* ctx, const char* ids_name, int** occur
     ss << plugin_
        << "::getOccurrences("
        << "uri='" << uri << "'"
+       << ", mode='" << imas::uda::convert_imas_to_uda<imas::uda::OpenMode>(OPEN_PULSE) << "'"
        << ", ids='" << ids_name << "'"
        << ")";
 
@@ -1390,6 +1391,7 @@ void UDABackend::list_filled_paths(Context* ctx, const char* dataobjectname, cha
     ss << plugin_
        << "::listFilledPaths("
        << "uri='" << uri << "'"
+       << ", mode='" << imas::uda::convert_imas_to_uda<imas::uda::OpenMode>(OPEN_PULSE) << "'"
        << ", ids='" << dataobjectname << "'"
        << ")";
 

From 950dd2bd1ea74a86dccd490c7aae01b7f7207f8e Mon Sep 17 00:00:00 2001
From: Prasad <prasad.sawantdesai@gmail.com>
Date: Wed, 29 Apr 2026 13:53:26 +0200
Subject: [PATCH 07/16] build MDSPLUS models based on imas_data_dictionary pypi
 package (#47)

---
 CMakeLists.txt                           |   5 +
 common/cmake/ALBuildDataDictionary.cmake | 136 ++++++++++++++++-------
 2 files changed, 101 insertions(+), 40 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index a7eb46a0..8ef14970 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -123,6 +123,9 @@ if(WIN32)
   find_package(dlfcn-win32 CONFIG REQUIRED)
 endif()
 
+# build AL_CORE library only if backend is enabled
+if(AL_BACKEND_HDF5 OR AL_BACKEND_MDSPLUS OR AL_BACKEND_UDA OR AL_BACKEND_UDAFAT OR AL_PYTHON_BINDINGS)
+
 # Core dependencies
 set(Boost_USE_MULTITHREADED FALSE)
 find_package(
@@ -239,6 +242,8 @@ if(AL_PYTHON_BINDINGS)
   include(skbuild.cmake)
 endif()
 
+endif() # AL core library (AL_BACKEND_HDF5 OR AL_BACKEND_MDSPLUS OR AL_BACKEND_UDA OR AL_BACKEND_UDAFAT OR AL_PYTHON_BINDINGS)
+
 
 # MDSplus models
 # ##############################################################################
diff --git a/common/cmake/ALBuildDataDictionary.cmake b/common/cmake/ALBuildDataDictionary.cmake
index 7961b623..a14854f2 100644
--- a/common/cmake/ALBuildDataDictionary.cmake
+++ b/common/cmake/ALBuildDataDictionary.cmake
@@ -38,63 +38,119 @@ else()
 endif()
 
 if( NOT AL_DOWNLOAD_DEPENDENCIES AND NOT AL_DEVELOPMENT_LAYOUT )
-  # The DD easybuild module should be loaded, use that module:
-  # Create Python venv first and install imas_data_dictionary
+  # Check if imas_data_dictionary is already available in the current Python environment
+  execute_process(
+    COMMAND ${PYTHON_EXECUTABLE} -c "import imas_data_dictionary"
+    RESULT_VARIABLE _IDD_IMPORT_RESULT
+    OUTPUT_QUIET
+    ERROR_QUIET
+  )
+
   if(NOT EXISTS "${_VENV_PYTHON}")
-    execute_process(
-      COMMAND ${PYTHON_EXECUTABLE} -m venv dd_build_env
-      WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}
-      RESULT_VARIABLE _VENV_EXITCODE
-      OUTPUT_VARIABLE _VENV_OUTPUT
-      ERROR_VARIABLE _VENV_ERROR
-    )
-    
+    if(_IDD_IMPORT_RESULT)
+      # if not available in the current environment create a dd_build_env and pip-install it
+      execute_process(
+        COMMAND ${PYTHON_EXECUTABLE} -m venv dd_build_env
+        WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}
+        RESULT_VARIABLE _VENV_EXITCODE
+        OUTPUT_VARIABLE _VENV_OUTPUT
+        ERROR_VARIABLE _VENV_ERROR
+      )
+    else()
+      # IMAS-Data-Dictioanry is already available, just create environment for saxonche by pulling site packages
+      execute_process(
+        COMMAND ${PYTHON_EXECUTABLE} -m venv --system-site-packages dd_build_env
+        WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}
+        RESULT_VARIABLE _VENV_EXITCODE
+        OUTPUT_VARIABLE _VENV_OUTPUT
+        ERROR_VARIABLE _VENV_ERROR
+      )
+    endif()
+
     if(_VENV_EXITCODE)
       message(STATUS "venv stdout: ${_VENV_OUTPUT}")
       message(STATUS "venv stderr: ${_VENV_ERROR}")
       message(FATAL_ERROR "Failed to create venv (exit code: ${_VENV_EXITCODE}). Ensure Python has venv module installed: python -m venv --help")
     endif()
-    
-    if(DEFINED DD_VERSION)
+
+    if(_IDD_IMPORT_RESULT)
+      # pip-install imas_data_dictionary only when not already present.
+      if(DEFINED DD_VERSION AND DD_VERSION MATCHES "^[0-9]")
+        message(STATUS "Installing imas_data_dictionary==${DD_VERSION} from PyPI")
+        execute_process(
+          COMMAND ${_VENV_PIP} install imas_data_dictionary==${DD_VERSION}
+          RESULT_VARIABLE _PIP_EXITCODE
+          OUTPUT_VARIABLE _PIP_OUTPUT
+          ERROR_VARIABLE _PIP_ERROR
+        )
+      else()
+        if(DEFINED DD_VERSION AND NOT DD_VERSION STREQUAL "")
+          message(WARNING
+            "DD_VERSION='${DD_VERSION}' looks like a git ref which can be used when AL_DOWNLOAD_DEPENDECY=OFF. "
+            "Installing the latest imas_data_dictionary from PyPI. "
+            "Pass a numeric version (e.g. -DDD_VERSION=4.1.0) to use a specific release.")
+        else()
+          message(WARNING
+            "DD_VERSION is not set. Installing the latest imas_data_dictionary from PyPI. "
+            "Pass -DDD_VERSION=<x.y.z> to use a specific release.")
+        endif()
+        execute_process(
+          COMMAND ${_VENV_PIP} install imas_data_dictionary
+          RESULT_VARIABLE _PIP_EXITCODE
+          OUTPUT_VARIABLE _PIP_OUTPUT
+          ERROR_VARIABLE _PIP_ERROR
+        )
+      endif()
+
+      if(_PIP_EXITCODE)
+        message(STATUS "imas_data_dictionary pip output: ${_PIP_OUTPUT}")
+        message(STATUS "imas_data_dictionary pip error: ${_PIP_ERROR}")
+        message(FATAL_ERROR "Failed to install imas_data_dictionary dependency (exit code: ${_PIP_EXITCODE}). Check network connectivity and Python wheel compatibility.")
+      endif()
+
+      # Report which version was actually installed
       execute_process(
-        COMMAND ${_VENV_PIP} install imas_data_dictionary==${DD_VERSION}
-        RESULT_VARIABLE _PIP_EXITCODE
-        OUTPUT_VARIABLE _PIP_OUTPUT
-        ERROR_VARIABLE _PIP_ERROR
+        COMMAND ${_VENV_PYTHON} -c
+          "import importlib.metadata; print(importlib.metadata.version('imas_data_dictionary'))"
+        OUTPUT_VARIABLE _IDD_INSTALLED_VERSION
+        OUTPUT_STRIP_TRAILING_WHITESPACE
+        ERROR_QUIET
       )
-    else()
+      if(_IDD_INSTALLED_VERSION)
+        message(STATUS "Using imas_data_dictionary version ${_IDD_INSTALLED_VERSION}")
+      endif()
+    endif()
+
+    execute_process(
+      COMMAND ${_VENV_PYTHON} -c "import saxonche"
+      RESULT_VARIABLE _SAXONCHE_CHECK
+      OUTPUT_QUIET
+      ERROR_QUIET
+    )
+    if(_SAXONCHE_CHECK)
       execute_process(
-        COMMAND ${_VENV_PIP} install imas_data_dictionary
+        COMMAND ${_VENV_PYTHON} -m pip install saxonche
         RESULT_VARIABLE _PIP_EXITCODE
         OUTPUT_VARIABLE _PIP_OUTPUT
         ERROR_VARIABLE _PIP_ERROR
       )
-    endif()
-    
-    if(_PIP_EXITCODE)
-      message(STATUS "imas_data_dictionary pip output: ${_PIP_OUTPUT}")
-      message(STATUS "imas_data_dictionary pip error: ${_PIP_ERROR}")
-      message(FATAL_ERROR "Failed to install imas_data_dictionary dependency (exit code: ${_PIP_EXITCODE}). Check network connectivity and Python wheel compatibility.")
-    endif()
-    
-    execute_process(
-      COMMAND ${_VENV_PIP} install saxonche
-      RESULT_VARIABLE _PIP_EXITCODE
-      OUTPUT_VARIABLE _PIP_OUTPUT
-      ERROR_VARIABLE _PIP_ERROR
-    )
-    
-    if(_PIP_EXITCODE)
-      message(STATUS "saxonche pip output: ${_PIP_OUTPUT}")
-      message(STATUS "saxonche pip error: ${_PIP_ERROR}")
-      message(FATAL_ERROR "Failed to install saxonche dependency (exit code: ${_PIP_EXITCODE}). Check network connectivity and Python wheel compatibility.")
+      
+      if(_PIP_EXITCODE)
+        message(STATUS "saxonche pip output: ${_PIP_OUTPUT}")
+        message(STATUS "saxonche pip error: ${_PIP_ERROR}")
+        message(FATAL_ERROR "Failed to install saxonche dependency (exit code: ${_PIP_EXITCODE}). Check network connectivity and Python wheel compatibility.")
+      endif()
     endif()
   endif()
 # Set up idsinfo command path
-if(WIN32)
-  set(_IDSINFO_COMMAND "${CMAKE_CURRENT_BINARY_DIR}/dd_build_env/Scripts/idsinfo.exe")
+if(_IDD_IMPORT_RESULT)
+  if(WIN32)
+    set(_IDSINFO_COMMAND "${CMAKE_CURRENT_BINARY_DIR}/dd_build_env/Scripts/idsinfo.exe")
+  else()
+    set(_IDSINFO_COMMAND "${CMAKE_CURRENT_BINARY_DIR}/dd_build_env/bin/idsinfo")
+  endif()
 else()
-  set(_IDSINFO_COMMAND "${CMAKE_CURRENT_BINARY_DIR}/dd_build_env/bin/idsinfo")
+  find_program(_IDSINFO_COMMAND NAMES idsinfo REQUIRED)
 endif()
 
   # Use idsinfo idspath command from venv to get the path to IDSDef.xml or data_dictionary.xml

From ceab030a1bab236e19140370718e805ca86d06b4 Mon Sep 17 00:00:00 2001
From: Prasad <prasad.sawantdesai@gmail.com>
Date: Mon, 4 May 2026 13:46:47 +0200
Subject: [PATCH 08/16] 
 fix/allow-pip-to-fetch-runtime-dependencies-during-isolated-install (#48)

---
 CMakeLists.txt                            | 10 ++-
 README.md                                 | 87 ++++++-----------------
 common/doc_common/building_installing.rst |  7 +-
 docs/source/user_guide/installation.rst   | 33 +++++++--
 skbuild.cmake                             |  1 +
 5 files changed, 61 insertions(+), 77 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 8ef14970..9f14738a 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -23,9 +23,13 @@ option(AL_BACKEND_MDSPLUS "Build the MDSplus backend" OFF)
 option(AL_BACKEND_HDF5 "Build the HDF5 backend" ON)
 option(AL_BACKEND_UDA "Build the UDA backend" OFF)
 option(AL_BACKEND_UDAFAT "Build the UDA backend (use FAT UDA)" OFF)
-include(CMakeDependentOption)
-cmake_dependent_option(AL_BUILD_MDSPLUS_MODELS "Build MDSplus models" ON
-AL_BACKEND_MDSPLUS OFF)
+# AL_BUILD_MDSPLUS_MODELS defaults to ON when AL_BACKEND_MDSPLUS is ON, otherwise OFF.
+# This can be overridde by user by setting AL_BUILD_MDSPLUS_MODELS explicitly to ON or OFF.
+if(AL_BACKEND_MDSPLUS)
+  option(AL_BUILD_MDSPLUS_MODELS "Build MDSplus models" ON)
+else()
+  option(AL_BUILD_MDSPLUS_MODELS "Build MDSplus models" OFF)
+endif()
 
 # Configuration options for python bindings
 # ##############################################################################
diff --git a/README.md b/README.md
index d487ef9b..70a0480b 100644
--- a/README.md
+++ b/README.md
@@ -17,45 +17,35 @@ This repository contains the **Lowlevel components of the Access Layer**:
 - **MDS+ model logic** for creating the models required by the MDS+ backend
 
 
-## Quick Installation
-
-Install IMAS-Core with a single command:
-
-```bash
-pip install imas-core
-python -c "import imas_core"
-```
-
-That's it! No need to compile or configure anything.
-
-## Features
-
-- ✅ **Easy to Install** - Single `pip install` command
-- ✅ **Multiple Formats** - HDF5, MDSplus, UDA, in-memory, and more
-- ✅ **Cross-Platform** - Works on Linux, macOS, and Windows
-- ✅ **IMAS Standard** - Access standardized fusion data structures
-- ✅ **Read & Write** - Both data access and creation supported
-
 ## Installation Options
 
-### For Python Users (Recommended)
+### For Python Users
 
 ```bash
-# Simple install from PyPI for Python applications
+# Install from PyPI
 pip install imas-core
 
 # Verify installation
 python -c "import imas; print(imas.__version__)"
 ```
 
-
 ### For Developers
 
-See [Building from Source](docs/source/user_guide/installation.rst) for detailed build instructions.
+To build IMAS-Core from source:
+
+```bash
+git clone https://github.com/iterorganization/IMAS-Core.git
+cd IMAS-Core
+cmake -Bbuild -GNinja -DAL_PYTHON_BINDINGS=ON -DCMAKE_INSTALL_PREFIX="$(pwd)/test-install"
+cmake --build build --target install
+```
+
+See [Developer Guide](docs/source/developers/index.rst) for build instructions.
+
 
 ## Using IMAS-Core with High-Level Languages
 
-When IMAS-Core is built and installed via CMake, it creates a complete runtime environment with:
+When IMAS-Core is built and installed via CMake, it installs:
 
 - **C/C++ Libraries** (`libal.so`) with full headers
 - **Python Bindings** (`imas_core` Python package)
@@ -74,79 +64,45 @@ export HDF5_USE_FILE_LOCKING=FALSE
 export PYTHONPATH="/path/to/install/lib/pythonX.X/site-packages:$PYTHONPATH"
 ```
 
-Then use IMAS-Core from your preferred language:
+Then use IMAS-Core from the required language:
 - **Python**: `import imas` (see examples above)
 - **C/C++**: Link against `libal.so` with provided headers
 - **Fortran**: Use pkg-config to get compiler flags
 - **Java**: Use `imas.jar` in your classpath
 - **MATLAB**: Add MEX directory to MATLAB path
 
+See [Building from Source](docs/source/user_guide/installation.rst) for detailed build instructions.
 
 ## Documentation
 
-- **[User Guide](docs/source/user_guide/index.rst)** - Complete user documentation
+- **[User Guide](docs/source/user_guide/index.rst)** - User documentation
 - **[Installation Guide](docs/source/user_guide/installation.rst)** - Installation instructions
 - **[Backends Guide](docs/source/user_guide/backends_guide.rst)** - Available data backends
 - **[URIs Guide](docs/source/user_guide/uris_guide.rst)** - Data entry URI documentation
 - **[Configuration](docs/source/user_guide/configuration.rst)** - Configuration options
 - **[FAQ](docs/source/faq.rst)** - Frequently asked questions
-- **[Troubleshooting](docs/source/troubleshooting.rst)** - Common issues & solutions
-
-## System Requirements
+- **[Troubleshooting](docs/source/troubleshooting.rst)** - Troubleshooting
 
-- **Python**: 3.8 or newer 
-- **OS**: Linux, macOS, or Windows
-- **pip**: 19.0 or newer
 
 ## Available Backends
 
-IMAS-Core supports multiple data storage formats:
+IMAS-Core supports these storage backends:
 
 | Backend | Use Case | Remote | File-based |
 |---------|----------|--------|-----------|
 | **HDF5** | Default, local storage | No | Yes |
 | **MDSplus** | ITER experiments | Yes | No |
 | **UDA** | Distributed access | Yes | No |
-| **Memory** | Testing, IPC | No | No |
+| **Memory** | Testing | No | No |
 | **FlexBuffers** | Message passing | No | Yes |
 | **ASCII** | Debugging | No | Yes |
 
-## Troubleshooting
-
-**Can't find file?**
-```python
-# Check file path
-import os
-print(os.path.exists('/path/to/file.h5'))
-```
 
-**Need help?**
+**Help**
 - See [Troubleshooting Guide](docs/source/troubleshooting.rst)
 - Check [FAQ](docs/source/faq.rst)
 - Open an [Issue on GitHub](https://github.com/iterorganization/IMAS-Core/issues)
 
-## What's Included?
-
-IMAS-Core provides:
-
-- **Python API** - Full Python bindings with NumPy support
-- **Multiple Backends** - HDF5, MDSplus, UDA, and more
-- **Data Creation** - Create and populate IMAS IDS structures
-- **Data Access** - Read from multiple sources transparently
-- **Standard Format** - IMAS standardized data structures
-
-## For Developers
-
-To build IMAS-Core from source:
-
-```bash
-git clone https://github.com/iterorganization/IMAS-Core.git
-cd IMAS-Core
-cmake -Bbuild -GNinja -DAL_PYTHON_BINDINGS=ON -DCMAKE_INSTALL_PREFIX="$(pwd)/test-install"
-cmake --build build --target install
-```
-
-See [Developer Guide](docs/source/developers/index.rst) for detailed instructions.
 
 ## Links
 
@@ -165,4 +121,3 @@ IMAS-Core is released under the [LGPL-3.0 License](LICENSE.txt)
 - **Email**: imas-support@iter.org
 - **Documentation**: https://imas-core.readthedocs.io/
 - **Issues**: https://github.com/iterorganization/IMAS-Core/issues
-
diff --git a/common/doc_common/building_installing.rst b/common/doc_common/building_installing.rst
index a5571fb3..6394abeb 100644
--- a/common/doc_common/building_installing.rst
+++ b/common/doc_common/building_installing.rst
@@ -227,9 +227,10 @@ Configuration options
     -   ``AL_BACKEND_MDSPLUS``, allowed values ``ON`` or ``OFF`` *(default)*.
         Enable/disable the MDSplus backend.
 
-        -   ``AL_BUILD_MDSPLUS_MODELS``, allowed values ``ON`` *(default)* or ``OFF``,
-            only available when the MDSplus backend is enabled. Enable building MDSplus
-            models for the selected Data Dictionary version.
+        -   ``AL_BUILD_MDSPLUS_MODELS``, allowed values ``ON`` or ``OFF``.
+            Enable building MDSplus models for the selected Data Dictionary version.
+            Defaults to ``ON`` when ``AL_BACKEND_MDSPLUS`` is enabled, ``OFF`` otherwise.
+            Can be overridden by user to explicitly enable or disable building MDSplus models.
 
     -   ``AL_BACKEND_UDA``, allowed values ``ON`` or ``OFF`` *(default)*. Enable/disable
         the UDA backend.
diff --git a/docs/source/user_guide/installation.rst b/docs/source/user_guide/installation.rst
index dc2f77bd..9fb4c633 100644
--- a/docs/source/user_guide/installation.rst
+++ b/docs/source/user_guide/installation.rst
@@ -219,9 +219,10 @@ Configuration options
     -   ``AL_BACKEND_MDSPLUS``, allowed values ``ON`` or ``OFF`` *(default)*.
         Enable/disable the MDSplus backend.
 
-        -   ``AL_BUILD_MDSPLUS_MODELS``, allowed values ``ON`` *(default)* or ``OFF``,
-            only available when the MDSplus backend is enabled. Enable building MDSplus
-            models for the selected Data Dictionary version.
+        -   ``AL_BUILD_MDSPLUS_MODELS``, allowed values ``ON`` or ``OFF``.
+            Enable building MDSplus models for the selected Data Dictionary version.
+            Defaults to ``ON`` when ``AL_BACKEND_MDSPLUS`` is enabled, ``OFF`` otherwise.
+            Can be overridden by user to explicitly enable or disable building MDSplus models.
 
     -   ``AL_BACKEND_UDA``, allowed values ``ON`` or ``OFF`` *(default)*. Enable/disable
         the UDA backend.
@@ -240,8 +241,30 @@ Configuration options
         ONLY the documentation will be built (needs ``AL_HLI_DOCS=ON``). Regardless of
         other configuration options, nothing else will be built.
     -   ``AL_PYTHON_BINDINGS``, allowed values ``ON`` *(default when building the Python
-        API)* or ``OFF`` *(default when not building the Python API)*. When enabled, this
-        builds the Access Layer Python lowlevel bindings.
+        API)* or ``OFF`` *(default when not building the Python API)*. This CMake option 
+        controls whether and how the `imas_core` Python package is built when installing 
+        through CMake.
+
+        | Value | When to use |
+        |---|---|
+        | `OFF` | Default for CMake builds. Build and install only the native IMAS-Core library, without Python bindings. |
+        | `ON` | Build the `imas_core` wheel using pip's normal build isolation. Build dependencies will be installed by pip. |
+        | `no-build-isolation` | Build the `imas_core` wheel using the current Python environment. Use this when build dependencies like `numpy` are already installed. |
+        | `editable` or `e` | Development mode. Install `imas_core` with `pip install --editable`, so Python changes can be used without reinstalling. |
+
+        When CMake installs the Python bindings, it first builds a local wheel and then
+        installs that wheel with `pip install --no-index --no-deps --find-links
+        <build>/dist`. 
+        `--no-index` prevents pip from searching PyPI or another package
+        index, and 
+        `--no-deps` prevents pip from installing or upgrading dependencies.
+        This keeps the CMake install step local and reproducible: only the wheel built
+        by this build is installed, and dependencies are expected to be provided by the
+        user's environment or system installation.
+
+        When not using CMake to build the Python bindings, you can install the `imas_core` with `pip install .`
+        command without specifying above options. `imas_core` will install with pip's normal build isolation.
+
 
 -   **Dependency configuration options**
 
diff --git a/skbuild.cmake b/skbuild.cmake
index ab217342..facd0058 100644
--- a/skbuild.cmake
+++ b/skbuild.cmake
@@ -52,6 +52,7 @@ set_target_properties(
 install(CODE "execute_process(COMMAND ${Python_EXECUTABLE} 
 -m pip install imas_core
 --no-index
+--no-deps
 --prefix=${CMAKE_INSTALL_PREFIX}
 --find-links ${CMAKE_CURRENT_BINARY_DIR}/dist/
 )"

From f2852fd6b927ae893f9376170fbde607f2f0ae82 Mon Sep 17 00:00:00 2001
From: prasad-sawantdesai <prasad.sawantdesai@gmail.com>
Date: Mon, 4 May 2026 16:33:31 +0200
Subject: [PATCH 09/16] added documentation about mdsplusIMASDB4to5 tool

---
 docs/source/user_guide/backends_guide.rst | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/docs/source/user_guide/backends_guide.rst b/docs/source/user_guide/backends_guide.rst
index f918a7ea..f40dec61 100644
--- a/docs/source/user_guide/backends_guide.rst
+++ b/docs/source/user_guide/backends_guide.rst
@@ -52,6 +52,11 @@ This backend imposes some limitations on the data that can be stored, see
     This backend has been around and stable for a longer time, so most older IMAS
     data is stored in this format.
 
+To map an existing MDSplus ``imasdb`` from the Access Layer 4 layout to the
+Access Layer 5 layout, use ``mdsplusIMASDB4to5``. For example,
+``mdsplusIMASDB4to5 --path $HOME/public --database ITER --dry-run`` shows the
+directory and link changes without modifying the data.
+
 
 .. _uda backend:
 

From 7d27a5fc9a64542e05561040f1a2668751c08518 Mon Sep 17 00:00:00 2001
From: Louwrensth <Louwrensth@users.noreply.github.com>
Date: Fri, 15 May 2026 13:56:24 +0000
Subject: [PATCH 10/16] ci: add dependabot.yml to update github-actions

---
 .github/dependabot.yml | 13 +++++++++++++
 1 file changed, 13 insertions(+)
 create mode 100644 .github/dependabot.yml

diff --git a/.github/dependabot.yml b/.github/dependabot.yml
new file mode 100644
index 00000000..3ba3d5da
--- /dev/null
+++ b/.github/dependabot.yml
@@ -0,0 +1,13 @@
+# Please see the documentation for all configuration options:
+# https://docs.github.com/code-security/dependabot/dependabot-version-updates/configuration-options-for-the-dependabot.yml-file
+
+version: 2
+updates:
+  # Enable version updates for Github Actions
+  - package-ecosystem: "github-actions"
+    # Look for `/.github/workflows` and `/action.yml` or `.yaml`
+    directory: "/"
+    # Check for updates once a week
+    schedule:
+      interval: "weekly"
+

From 775c03d50d52ff870c388100a1a9ae9dd915b73a Mon Sep 17 00:00:00 2001
From: "dependabot[bot]" <49699333+dependabot[bot]@users.noreply.github.com>
Date: Mon, 18 May 2026 11:46:10 +0000
Subject: [PATCH 11/16] Bump actions/checkout from 4 to 6

Bumps [actions/checkout](https://github.com/actions/checkout) from 4 to 6.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](https://github.com/actions/checkout/compare/v4...v6)

---
updated-dependencies:
- dependency-name: actions/checkout
  dependency-version: '6'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>
---
 .github/workflows/docs.yml   | 2 +-
 .github/workflows/wheels.yml | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/.github/workflows/docs.yml b/.github/workflows/docs.yml
index 715b12f0..b6aee918 100644
--- a/.github/workflows/docs.yml
+++ b/.github/workflows/docs.yml
@@ -10,7 +10,7 @@ jobs:
     
     steps:
       - name: Checkout code
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
         with:
           fetch-depth: 0  # Fetch full history for git describe to work
 
diff --git a/.github/workflows/wheels.yml b/.github/workflows/wheels.yml
index 24bda5f5..1a06b18a 100644
--- a/.github/workflows/wheels.yml
+++ b/.github/workflows/wheels.yml
@@ -199,7 +199,7 @@ jobs:
             FMT_REF: "11.1.4"
 
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
         with:
           fetch-depth: 0  # unshallow for setuptools-scm.get_version to discover tags
 

From f9f15cab90f10c913c3ad9e53b1353617c00da01 Mon Sep 17 00:00:00 2001
From: "dependabot[bot]" <49699333+dependabot[bot]@users.noreply.github.com>
Date: Mon, 18 May 2026 11:46:15 +0000
Subject: [PATCH 12/16] Bump pypa/cibuildwheel from 3.1.0 to 3.4.1

Bumps [pypa/cibuildwheel](https://github.com/pypa/cibuildwheel) from 3.1.0 to 3.4.1.
- [Release notes](https://github.com/pypa/cibuildwheel/releases)
- [Changelog](https://github.com/pypa/cibuildwheel/blob/main/docs/changelog.md)
- [Commits](https://github.com/pypa/cibuildwheel/compare/v3.1.0...v3.4.1)

---
updated-dependencies:
- dependency-name: pypa/cibuildwheel
  dependency-version: 3.4.1
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>
---
 .github/workflows/wheels.yml | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/.github/workflows/wheels.yml b/.github/workflows/wheels.yml
index 1a06b18a..b013b044 100644
--- a/.github/workflows/wheels.yml
+++ b/.github/workflows/wheels.yml
@@ -281,7 +281,7 @@ jobs:
           path: C:\vcpkg\installed
           key: ${{ matrix.os }}-${{ env.cache-name }}-a
 
-      - uses: pypa/cibuildwheel@v3.1.0
+      - uses: pypa/cibuildwheel@v3.4.1
         if: startsWith(matrix.os, 'ubuntu-')
         env:
           CIBW_BUILD: cp${{ matrix.python }}-${{ matrix.platform_id }}
@@ -334,7 +334,7 @@ jobs:
           output-dir: wheelhouse
           config-file: "{package}/pyproject.toml"
 
-      - uses: pypa/cibuildwheel@v3.1.0
+      - uses: pypa/cibuildwheel@v3.4.1
         if: startsWith(matrix.os, 'macos-')
         env:
           CIBW_BUILD: cp${{ matrix.python }}-${{ matrix.platform_id }}

From 69e7523ffe5a9f65a6b2a1df15d643c1775f4e5c Mon Sep 17 00:00:00 2001
From: "dependabot[bot]" <49699333+dependabot[bot]@users.noreply.github.com>
Date: Mon, 18 May 2026 11:46:20 +0000
Subject: [PATCH 13/16] Bump actions/cache from 4 to 5

Bumps [actions/cache](https://github.com/actions/cache) from 4 to 5.
- [Release notes](https://github.com/actions/cache/releases)
- [Changelog](https://github.com/actions/cache/blob/main/RELEASES.md)
- [Commits](https://github.com/actions/cache/compare/v4...v5)

---
updated-dependencies:
- dependency-name: actions/cache
  dependency-version: '5'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>
---
 .github/workflows/wheels.yml | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/.github/workflows/wheels.yml b/.github/workflows/wheels.yml
index b013b044..79777139 100644
--- a/.github/workflows/wheels.yml
+++ b/.github/workflows/wheels.yml
@@ -226,7 +226,7 @@ jobs:
 
       - name: Restore cibuildwheel cache
         id: cache
-        uses: actions/cache@v4
+        uses: actions/cache@v5
         with:
           path: |
             ~\AppData\Local\pypa\cibuildwheel\Cache
@@ -238,7 +238,7 @@ jobs:
       - name: Cache restore windows deps
         if: startsWith(matrix.os, 'windows')
         id: cache-win-deps
-        uses: actions/cache/restore@v4
+        uses: actions/cache/restore@v5
         env:
           cache-name: win-deps
         with:
@@ -274,7 +274,7 @@ jobs:
         # the cache redundantly doesn't compare to the time it takes to rebuild vcpkg packages.
         if: ${{ always()  && startsWith(matrix.os, 'windows') }}
         id: cache-win-deps-save
-        uses: actions/cache/save@v4
+        uses: actions/cache/save@v5
         env:
           cache-name: win-deps
         with:

From 2c7a36a80ab71a16e726ad5d6b4d9e9524b396a6 Mon Sep 17 00:00:00 2001
From: "dependabot[bot]" <49699333+dependabot[bot]@users.noreply.github.com>
Date: Mon, 18 May 2026 11:46:24 +0000
Subject: [PATCH 14/16] Bump actions/download-artifact from 4 to 8

Bumps [actions/download-artifact](https://github.com/actions/download-artifact) from 4 to 8.
- [Release notes](https://github.com/actions/download-artifact/releases)
- [Commits](https://github.com/actions/download-artifact/compare/v4...v8)

---
updated-dependencies:
- dependency-name: actions/download-artifact
  dependency-version: '8'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>
---
 .github/workflows/wheels.yml | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/.github/workflows/wheels.yml b/.github/workflows/wheels.yml
index 79777139..144ed758 100644
--- a/.github/workflows/wheels.yml
+++ b/.github/workflows/wheels.yml
@@ -397,7 +397,7 @@ jobs:
       name: testpypi
       url: https://test.pypi.org/p/imas-core
     steps:
-      - uses: actions/download-artifact@v4
+      - uses: actions/download-artifact@v8
         with:
           pattern: cibw-wheels-*
           merge-multiple: true  # avoid artifact subdirs below wheelhouse
@@ -424,7 +424,7 @@ jobs:
       name: pypi
       url: https://pypi.org/p/imas-core
     steps:
-      - uses: actions/download-artifact@v4
+      - uses: actions/download-artifact@v8
         with:
           pattern: cibw-wheels-*
           merge-multiple: true  # avoid artifact subdirs below wheelhouse

From b8825a9912183808128c7cf24adbe1423b08ac8d Mon Sep 17 00:00:00 2001
From: "dependabot[bot]" <49699333+dependabot[bot]@users.noreply.github.com>
Date: Mon, 18 May 2026 11:46:28 +0000
Subject: [PATCH 15/16] Bump actions/upload-artifact from 4 to 7

Bumps [actions/upload-artifact](https://github.com/actions/upload-artifact) from 4 to 7.
- [Release notes](https://github.com/actions/upload-artifact/releases)
- [Commits](https://github.com/actions/upload-artifact/compare/v4...v7)

---
updated-dependencies:
- dependency-name: actions/upload-artifact
  dependency-version: '7'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>
---
 .github/workflows/docs.yml   | 2 +-
 .github/workflows/wheels.yml | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/.github/workflows/docs.yml b/.github/workflows/docs.yml
index b6aee918..1e1d0311 100644
--- a/.github/workflows/docs.yml
+++ b/.github/workflows/docs.yml
@@ -84,7 +84,7 @@ jobs:
 
       - name: Upload documentation artifact
         if: always()
-        uses: actions/upload-artifact@v4
+        uses: actions/upload-artifact@v7
         with:
           name: documentation
           path: docs/build/html/
diff --git a/.github/workflows/wheels.yml b/.github/workflows/wheels.yml
index 144ed758..736c8917 100644
--- a/.github/workflows/wheels.yml
+++ b/.github/workflows/wheels.yml
@@ -378,7 +378,7 @@ jobs:
           output-dir: wheelhouse
           config-file: "{package}/pyproject.toml"
 
-      - uses: actions/upload-artifact@v4
+      - uses: actions/upload-artifact@v7
         with:
           name: cibw-wheels-cp${{ matrix.python }}-${{ matrix.platform_id }}
           path: wheelhouse/*.whl

From 3ff289882a43bed7ebf47b96eddcad649760f4cc Mon Sep 17 00:00:00 2001
From: "dependabot[bot]" <49699333+dependabot[bot]@users.noreply.github.com>
Date: Mon, 18 May 2026 14:57:42 +0000
Subject: [PATCH 16/16] Bump actions/setup-python from 5 to 6

Bumps [actions/setup-python](https://github.com/actions/setup-python) from 5 to 6.
- [Release notes](https://github.com/actions/setup-python/releases)
- [Commits](https://github.com/actions/setup-python/compare/v5...v6)

---
updated-dependencies:
- dependency-name: actions/setup-python
  dependency-version: '6'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>
---
 .github/workflows/docs.yml   | 2 +-
 .github/workflows/wheels.yml | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/.github/workflows/docs.yml b/.github/workflows/docs.yml
index 1e1d0311..771659bf 100644
--- a/.github/workflows/docs.yml
+++ b/.github/workflows/docs.yml
@@ -15,7 +15,7 @@ jobs:
           fetch-depth: 0  # Fetch full history for git describe to work
 
       - name: Set up Python
-        uses: actions/setup-python@v5
+        uses: actions/setup-python@v6
         with:
           python-version: '3.11'
           cache: 'pip'
diff --git a/.github/workflows/wheels.yml b/.github/workflows/wheels.yml
index 736c8917..e74324d3 100644
--- a/.github/workflows/wheels.yml
+++ b/.github/workflows/wheels.yml
@@ -213,7 +213,7 @@ jobs:
       #       core.exportVariable('ACTIONS_CACHE_URL', process.env.ACTIONS_CACHE_URL || '');
       #       core.exportVariable('ACTIONS_RUNTIME_TOKEN', process.env.ACTIONS_RUNTIME_TOKEN || '')
 
-      - uses: actions/setup-python@v5
+      - uses: actions/setup-python@v6
         with:
           # python installation used when to start cibuildwheel
           python-version: "3.12"