Would be nice to have gradients for e.g. QRPackedQ, similar to what we have for Cholesky.
Contributor guide
Tech stack
None
Domain
backend
Issue type
feature
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
3
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
1-2 days
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
stale
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
clear
Prerequisites
Julia basicsautomatic differentiationQR decomposition
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
40
Research direction
Investigate the existing Cholesky gradient implementation in Zygote.jl (likely in src/compiler/chainrules.jl or similar) to understand the pattern. Examine the QR decomposition functions defined in Julia's LinearAlgebra standard library, specifically the QRPackedQ type. Check for any existing ChainRules.jl rules for QR or related discussion in the issue comments. Reach out to maintainers for guidance on the expected interface and potential pitfalls.
