Exciting News: I’m Joining Google Summer of Code 2026!

GSoC 2026
OpenSource
Python
HPC
quantum
Author

Chinmay Tangal

Published

May 21, 2026

A few months ago, I put together a GSoC proposal half-convinced it wouldn’t go anywhere. I’d been contributing to QuTiP for a while, understood the codebase well enough to spot a real problem, and figured — why not try?

I’m happy to share that I’ve been selected as a Google Summer of Code 2026 contributor! 🚀

What I’ll Be Working On

Here’s the problem: the HEOM solver in QuTiP is single-node. The entire hierarchy state lives in one vector on one machine, integrated with a single scipy ODE call. For small systems that’s fine. But push the hierarchy depth past 6, or work with anything beyond a few qubits, and you hit a memory cliff fast. There’s no workaround — it’s a structural limitation.

My project builds the distributed path that’s been missing: integrating PETSc and MPI into the solver so the ODE integration can run across multiple nodes on an HPC cluster.

The project will include:

  • Distributed data layout for the HEOM hierarchy across MPI ranks, designed to keep inter-rank communication local rather than all-to-all
  • PETSc TS integration for distributed vector and matrix operations and time integration
  • Correctness validation against the existing solver on standard benchmark systems
  • Performance benchmarks across hierarchy depths, system sizes, and node counts
  • HPC documentation and tutorials for running the solver on real cluster infrastructure

The existing solver stays completely untouched — if you don’t need distributed execution, nothing changes for you.

Looking Forward

I’ve spent the past few months going through the QuTiP codebase, submitting PRs, and getting a feel for how the project works. That groundwork made writing the proposal a lot more concrete — I wasn’t guessing at the architecture, I’d actually traced through it.

Now I get to spend the summer working on the part that genuinely interested me from the start: the design problem of distributing a coupled hierarchy without turning communication into the new bottleneck.

Over the next few months, I’ll be:

  • Profiling the existing solver and nailing down the distributed data layout with mentors
  • Building and testing the PETSc-based execution path
  • Validating correctness and running scaling benchmarks on HPC infrastructure
  • Documenting everything here as I go

Expect posts on the design decisions, the tricky bits, and probably a few dead ends along the way.

Acknowledgments

Thanks to the QuTiP team — especially my mentors Alex Pitchford and Eric Giguère — for taking on this project and for the feedback they gave during the proposal stage. Looking forward to the summer.

Following along, working on something related, or also doing GSoC this year? Feel free to reach out — always happy to talk HPC, open quantum systems, or open source.

TipInterested in QuTiP?

Check out the QuTiP documentation to learn more about quantum simulations in Python!

Tags: GSoC2026, HPC, OpenQuantumSystems, OpenSource, Python, QuTiP, NumFOCUS, PETSc, MPI