Source distributions for Conduit releases are hosted on github:


Conduit uses BLT as its core CMake build system. We leverage BLT as a git submodule, however github does not include submodule contents in its automatically created source tarballs. To avoid confusion, starting with v0.3.0 we provide our own source tarballs that include BLT.



(Extracted from Conduit’s Changelog)


  • General
  • Added Generic IO Handle class (relay::io::IOHandle) with C++ and Python APIs, tests, and docs.
  • Added rename_child method to Schema and Node
  • Added generation and install of for using-with-make example
  • Added datatype helpers for long long and long double
  • Added error for empty path fetch
  • Added C functions for setting error, warning, info handlers.
  • Added limited set of C bindings for DataType
  • Added C bindings for relay IO
  • Added several more functions to conduit node python interfaces
  • Blueprint
  • Added implicit point topology docs and example
  • Added julia and spiral mesh bp examples
  • Added mesh topology transformations to blueprint
  • Added polygonal mesh support to mesh blueprint
  • Added verify method for mesh blueprint nestset
  • Relay
  • Added ADIOS Support, enabling ADIOS read and write of Node objects.
  • Added a relay::mpi::io library that mirrors the API of relay::io, except that all functions take an MPI communicator. The functions are implemented in parallel for the ADIOS protocol. For other protocols, they will behave the same as the serial functions in relay::io. For the ADIOS protocol, the save() and save_merged() functions operate collectively within a communicator to enable multiple MPI ranks to save data to a single file as separate “domains”.
  • Added an add_time_step() function to that lets the caller append data collectively to an existing ADIOS file
  • Added a function to query the number of time steps and the number of domains in a ADIOS file.
  • Added versions of save and save_merged that take an options node.
  • Added C API for new save, save_merged functions.
  • Added method to list an HDF5 group’s child names
  • Added save and append methods to the HDF5 I/O interface
  • Added docs and examples for relay io


  • General
  • Changed mapping of c types to bit-width style to be compatible with C++11 std bit-width types when C++11 is enabled
  • Several improvements to uberenv, our automated build process, and building directions
  • Upgraded the type system with more explicit signed support
  • Relay
  • Improvements to the Silo mesh writer
  • Refactor to support both relay::io and relay::mpi::io namespaces.
  • Refactor to add support for steps and domains to I/O interfaces
  • Changed to only use libver latest setting for for hdf5 1.8 to minimize compatibility issues


  • General
  • Fixed bugs with std::vector gap methods
  • Fixed A few C function names in conduit_node.h
  • Fixed bug in python that was requesting unsigned array for signed cases
  • Fixed issue with Node::diff failing for string data with offsets
  • Fixes for building on BlueOS with the xl compiler
  • Blueprint
  • Fixed validity status for blueprint functions
  • Fixed improper error reporting for Blueprint references
  • Relay
  • Relay I/O exceptions are now forwarded to python
  • Fixed MPI send_with_schema bug when data was compact but not contiguous
  • Switched to use MPI bit-width style data type enums in relay::mpi



  • General
  • Added new Node::diff and Node::diff_compatible methods
  • Updated uberenv to use a newer spack and removed several custom packages
  • C++ Node::set methods now take const pointers for data
  • Added Python version of basic tutorial
  • Expanded the Node Python Capsule API
  • Added Python API bug fixes
  • Fixed API exports for static libs on Windows
  • Blueprint
  • Mesh Protocol
    • Removed unnecessary state member in the braid example
  • Added Multi-level Array Protocol (conduit::blueprint::mlarray)
  • Relay
  • Added bug fixes for Relay HDF5 support on Windows



  • General
  • Moved to use BLT ( as our core CMake-based build system
  • Bug fixes to support building on Visual Studio 2013
  • Bug fixes for conduit::Node in the List Role
  • Expose more of the Conduit API in Python
  • Use ints instead of bools in the Conduit C-APIs for wider compiler compatibility
  • Fixed memory leaks in conduit and conduit_relay
  • Blueprint
  • Mesh Protocol
    • Added support for multi-material fields via matsets (volume fractions and per-material values)
    • Added initial support for domain boundary info via adjsets for distributed-memory unstructured meshes
  • Relay
  • Major improvements conduit_relay I/O HDF5 support
    • Add heuristics with knobs for controlling use of HDF5 compact datasets and compression support
    • Improved error checking and error messages
  • Major improvements to conduit_relay_mpi support
    • Add support for reductions and broadcast
    • Add support zero-copy pass to MPI for a wide set of calls
    • Harden notion of known schema vs generic MPI support



  • General
  • Added fixes to support static builds on BGQ using xlc and gcc
  • Fixed missing install of fortran module files
  • Eliminated separate fortran libs by moving fortran symbols into their associated main libs
  • Changed Node::set_external to support const Node references
  • Refactored path and file systems utils functions for clarity.
  • Blueprint
  • Fixed bug with verify of mesh/coords for rectilinear case
  • Added support to the blueprint python module for the mesh and mcarray protocol methods
  • Added stand alone blueprint verify executable
  • Relay
  • Updated the version of civetweb used to avoid dlopen issues with SSL for static builds



  • General
  • Changes to clarify concepts in the conduit::Node API
  • Added const access to conduit::Node children and a new NodeConstIterator
  • Added support for building on Windows
  • Added more Python, C, and Fortran API support
  • Resolved several bugs across libraries
  • Resolved compiler warnings and memory leaks
  • Improved unit test coverage
  • Renamed source and header files for clarity and to avoid potential conflicts with other projects
  • Blueprint
  • Added verify support for the mcarray and mesh protocols
  • Added functions that create examples instances of mcarrays and meshes
  • Added memory layout transform helpers for mcarrays
  • Added a helper that creates a mesh blueprint index from a valid mesh
  • Relay
  • Added extensive HDF5 I/O support for reading and writing between HDF5 files and conduit Node trees
  • Changed I/O protocol string names for clarity
  • Refactored the relay::WebServer and the Conduit Node Viewer application
  • Added entangle, a python script ssh tunneling solution