---
id: pr-flash-attention-2393
repo: Dao-AILab/flash-attention
pr: 2393
title: 'Add FA4 CI: GitHub Actions workflow with Apptainer on B200 runner'
author: Johnsonms
date: '2026-04-02'
url: https://github.com/Dao-AILab/flash-attention/pull/2393
source_category: upstream-code
architectures:
- sm100
tags:
- benchmark kernel
- cuda kernel
techniques: []
hardware_features: []
kernel_types:
- attention
languages:
- cuda-cpp
captured_at: '2026-05-16'
status: merged
merge_sha: 4bc0ab1f0567670610ab884c80abbfba6fa17ab6
inclusion_reason: Search-matched CUDA kernel optimization PR; materialize diff/source before synthesis.
changed_paths:
- .github/actions/gpu-test/action.yml
- .github/workflows/ci.yml
- flash_attn/cute/cache_utils.py
- flash_attn/cute/pyproject.toml
- test_ci_local.sh
- tools/ci/README.md
- tools/ci/build_sif.sh
- tools/ci/docker/Dockerfile
- tools/ci/docker/build.sh
- tools/ci/docker/tag_and_push.sh
- tools/ci/fa4.def
- tools/ci/run_fa4_ci.py
artifact_dir: evidence/pull-bundles/flash-attention/gh-2393
head_ref_oid: a46b362665e2d4081631fe35a463f588b5d55659
---
# Add FA4 CI: GitHub Actions workflow with Apptainer on B200 runner

- Repository: `Dao-AILab/flash-attention`
- PR: [2393](https://github.com/Dao-AILab/flash-attention/pull/2393)
- Decision: `Search-matched CUDA kernel optimization PR; materialize diff/source before synthesis.`
- Reason: Search-matched CUDA kernel optimization PR; materialize diff/source before synthesis.

## Changed Paths

- `.github/actions/gpu-test/action.yml`
- `.github/workflows/ci.yml`
- `flash_attn/cute/cache_utils.py`
- `flash_attn/cute/pyproject.toml`
- `test_ci_local.sh`
- `tools/ci/README.md`
- `tools/ci/build_sif.sh`
- `tools/ci/docker/Dockerfile`
- `tools/ci/docker/build.sh`
- `tools/ci/docker/tag_and_push.sh`
- `tools/ci/fa4.def`
- `tools/ci/run_fa4_ci.py`

## Evidence Bundle

`evidence/pull-bundles/flash-attention/gh-2393`
