Runtimes
StarPU: A Unified Runtime System for Heterogeneous Multicore Architectures.
Kokkos: Kokkos C++ Performance Portability Programming EcoSystem: The Programming Model - Parallel Execution and Memory Abstraction.
Hybrid-Fortran: Accelerate with CUDA, OpenACC and OpenMP - Unified and Performance Portable.
XKaapi: A runtime for scheduling irregular fine grain tasks with data flow dependencies.
Intel® OpenMP: The Intel® OpenMP Runtime Library.
libgomp: The GNU OpenMP library.
libkomp: An Efficient OpenMP Runtime System for Both Fork-Join and Data Flow Paradigms.

Numerical software
Feel++: A poweful, expressive and scalable finite element embedded library in C++.
Freefem++: A partial differential equation solver. It has its own language. freefem scripts can solve multiphysics non linear systems in 2D and 3D.
Fenics: A popular open-source (LGPLv3) computing platform for solving partial differential equations (PDEs).
GenASiS: Object-oriented manifolds, operations, and solvers for large-scale physics simulations.

Linear Solvers
Mumps: MUltifrontal Massively Parallel sparse direct Solver.
PaStiX: A scientific library that provides a high performance parallel solver for very large sparse linear systems based on direct methods.

Linear Algebra
OpenBlas: An optimized BLAS library based on GotoBLAS2 1.13 BSD version.

Graph Partition
Scotch: A software package for graph and mesh/hypergraph partitioning, graph clustering, and sparse matrix ordering.
Zoltan: Parallel Partitioning, Load Balancing and Data-Management Services.

Fortran
Fortran Wiki: An open venue for discussing all aspects of the Fortran programming language and scientific computing.

Linux
Manjaro: Professional and user-friendly Linux at its best (my favorite OS for the moment, based on ArchLinux).
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