Tesseract Hackathon 2026

Compose a differentiable scientific workflow from multiple Tesseracts, and use end-to-end gradients to solve a real design, inference, or training problem.

Four weeks to build something that couldn't exist within a single framework. Compete for a share of the $20,000 prize pool and a head start on your next research paper.

A differentiable Tesseract pipeline Three Tesseracts built with different languages and differentiation strategies compose into one differentiable function, with gradients flowing backward through the whole pipeline. one differentiable function Tesseract A C++ · finite differences Tesseract B Julia · analytic adjoint Tesseract C Python · JAX autodiff ∂J/∂θ

The challenge

Use Tesseract to elevate differentiable systems#

Real scientific workflows span tools, languages, and machines, and that is exactly where gradients usually die. This year's challenge is to build a pipeline where they don't: multiple Tesseracts, one differentiable function, and an optimization, training, or inference loop that puts it to work.

Criteria

01 · compositionIt composes two or more Tesseracts across a real boundary

The components should disagree about how they compute, yet still compose into an end-to-end differentiable function. The boundary can be one of differentiation strategy, language, framework, or hardware. What matters is that it's a boundary that's otherwise hard to cross.

02 · gradientsThe gradients do the work

They drive a gradient-based optimizer, a training loop, or an inference scheme on a problem that can't be solved component by component, such as a coupled equilibrium, an inverse design, or a calibration. Show the objective improving and the recovered solution.

03 · framework fitThe workflow genuinely needs Tesseract

Your writeup should make the case for why this is a Tesseract problem: what was impossible or painful before (a language barrier, incompatible AD strategies, conflicting dependencies, a remote GPU, orchestration on HPC) that composition across the boundary resolves. We'd rather see a modest problem where Tesseract is clearly load-bearing than an ambitious one where it's a costume.

Two things worth knowing

Aim at a real problem

A prototype pointed at something a practitioner in the field would actually care about is how you win. For a sense of the bar, see last year's winning entries and the rocket-fin shape optimization case study that composes three Tesseracts across CAD, meshing, and an FEA solver.

Hack Tesseract if you need to

Hit a missing feature, a performance bottleneck, or a critical bug? Fork Tesseract and patch it yourself. We love to see teams that modify the software to fit their needs, as long as it's still recognizably Tesseract.

Tracks

Five ways in#

Pick the track that best describes your headline result. Cross-track submissions are fine; choose the track for the result you're proudest of.

01

Inverse design & shape optimization

A geometry/mesh/solver pipeline optimized end to end. Strongest entries cross a tool boundary (e.g. CAD or mesher ↔ solver) where the components differentiate differently: a finite-difference or surrogate-gradient mesher feeding an autodiff solver, an Enzyme-differentiated kernel composed with JAX, or an adjoint solver feeding autodiff post-processing.

02

Multi-physics & coupled systems

Two or more solvers from different domains coupled into one optimizable pipeline, with gradients flowing through the coupling. Ideally two-way, where each solver feeds back into the other and the optimum depends on their coupling.

03

Hybrid ML + mechanistic models

A learned component (closure, sub-grid model, surrogate, neural operator) trained by backpropagating through a physics solver that lives behind a Tesseract: the solver keeps its own container, language, and AD strategy, and gradients still flow from your loss, through the solver, into the network's weights. The interesting cases recover something physically meaningful, not just a black-box fit.

04

Differentiable inference & UQ

An expensive or black-box solver wrapped as a Tesseract and dropped into a probabilistic workflow (NumPyro, oryx, PyMC, an SBI scheme) for Bayesian calibration or an inverse problem. The solver may expose its Jacobian by autodiff or by finite differences; the composition with the inference engine is the contribution.

05

Differentiable graphics & rendering

A differentiable renderer, rasterizer, or geometry-processing component composed with a physics or ML Tesseract: inverse rendering, image-driven shape or material recovery, simulation-in-the-loop rendering. Gradients flow from a rendered image or geometric quantity back through the pipeline to the parameters that produced it.

The long game

From hackathon to research paper

A strong entry can have a second life. A novel composition, a working method, and results to show are already most of what a research paper needs, so a good submission doubles as a running start on your next publication. It's been done [1] [2] [3], and we'll happily work with the strongest teams to get there.

Timeline

Four weeks in August#

Aug 3
Challenge goes live
Registration opens and the clock starts. Join any time during the build period.
Aug 3–31
Build
Four weeks to build, with weekly office hours and the forum for questions and teammates.
Aug 31
Submissions close
11:59 PM, Anywhere on Earth.
Sep 21
Winners announced
Judging and feedback sessions run through mid-September.

Prizes

What's in it for you#

$20,000 total prize pool

Beyond the cash

Prize eligibility and tax details are covered in the Terms & Conditions.

Participate

How it works#

Eligibility

Open to everyone: hobbyists, PhD students, postdocs, research engineers, and industry researchers. Participate solo or in teams of up to 4 people. Registration is free and required to be eligible for prizes.

What to submit

  • A project that meets the challenge criteria: two or more composed Tesseracts, with end-to-end gradients solving a real problem.
  • Code written during the hackathon period, licensed under Apache 2.0.
  • A public GitHub repository with a README that lets others reproduce your results.
  • A short technical writeup (2–4 pages, or a detailed README) that names your track and makes the case for why the workflow needs Tesseract.
  • Optional: a demo video (5 minutes max) showing what you built and why it matters.

How we judge

Submissions are evaluated on, in roughly this order:

  1. Composition across a real boundary. The heart of the challenge.
  2. Gradients doing real work. A visible objective improving on a problem that can't be solved piecewise.
  3. The why-Tesseract case. Tesseract as load-bearing infrastructure, not a costume.
  4. A real application. A prototype with a line of sight to a genuine science or engineering problem beats a toy; domains we don't already have a demo for score higher.
  5. Execution & technical depth. Clean engineering that makes the pipeline scale, or forking and patching Tesseract itself to remove a blocker.
  6. Reproducibility & communication. Can others run it, and does the writeup explain it clearly, with visuals that support understanding?

How to submit

Submit your project through the submission form, with a link to your public GitHub repository. Then post your project on LinkedIn, tagging Pasteur Labs & ISI and Tesseract. That's it!

We also encourage you to share it in the forum showcase to show the community what you've built.

Resources

Everything you need to start building#

Join the challenge

Boundaries were made to be differentiated

Register now, join the forum, and spend four weeks in August building the pipeline your research has been missing.

Questions? Ask in the Hackathon channel on the Tesseract forum.