README: enhance build instructions

[nvswarren]

• Add much more information about installing build dependencies.
• Fix the verification command to use the actual Python module name,
  so that verification succeeds.

[greptile-apps]

Greptile Summary

This PR significantly expands the README build instructions with step-by-step guidance for system dependencies, CUDA environment setup, Python virtual environments, and additional pip packages, and also fixes the verification command to use the correct module name nvfuser_direct.

• Adds detailed apt-get install steps for CUDA toolkit, cuDNN, and dev libraries, plus a heredoc-based CUDA env-var setup block (now correctly using a quoted delimiter).
• Expands the Python dependency section with extra pip install commands for build-time and test-time packages, and separates transformer_engine into its own --no-build-isolation invocation.
• Adds venv to .gitignore to match the newly-recommended virtualenv venv workflow.

Confidence Score: 5/5

Documentation-only change with no runtime code affected; safe to merge after minor wording and flag fixes.

All changes are to README.md and .gitignore. The build instructions are substantially improved and the quoted heredoc delimiter correctly prevents unwanted variable expansion. The only findings are two spelling typos and a missing -y flag on a second apt-get install block — none of these block correct usage for an interactive reader.

README.md — two suite/suit typos and the missing -y on the cuDNN apt-get install block.

Important Files Changed

Filename	Overview
README.md	Large expansion of build instructions: adds system dependencies, CUDA env setup, virtualenv creation, additional pip packages, and GPU architecture selection; fixes verification command module name. Two "suite"→"suit" typos and one missing -y flag on apt-get install.
.gitignore	Adds venv to gitignore — correctly matches the virtual environment directory name used in the new README instructions.

Flowchart

%%{init: {'theme': 'neutral'}}%%
flowchart TD
    A[Clone repo with --recursive] --> B[Install system deps\napt-get: build-essential cmake\ncuda-toolkit llvm-dev etc]
    B --> C[Install cuDNN packages\nwith pinned versions]
    C --> D[Set up CUDA env vars\nin ~/.bashrc via quoted heredoc]
    D --> E[Create Python venv\nvirtualenv venv]
    E --> F[pip install -r requirements.txt]
    F --> G[pip install setuptools wheel numpy torch]
    G --> H[pip install test packages\ntvm-ffi pytest transformers etc]
    H --> I[pip install --no-build-isolation\ntransformer_engine pytorch]
    I --> J{Building in Docker?}
    J -- Yes --> K[Export TORCH_CUDA_ARCH_LIST]
    J -- No --> L[Build nvFuser\npip install --no-build-isolation -e python]
    K --> L
    L --> M[Verify: import nvfuser_direct as nvfuser]

Loading

%%{init: {'theme': 'base', 'themeVariables': {"darkMode": true, "background": "#0d1117", "primaryColor": "#21262d", "primaryTextColor": "#e6edf3", "primaryBorderColor": "#8b949e", "lineColor": "#8b949e", "textColor": "#e6edf3", "edgeLabelBackground": "#161b22", "actorBkg": "#21262d", "actorBorder": "#8b949e", "actorTextColor": "#e6edf3", "actorLineColor": "#8b949e", "signalColor": "#8b949e", "signalTextColor": "#e6edf3", "noteBkgColor": "#373320", "noteBorderColor": "#d4a72c", "noteTextColor": "#f0e6c0", "labelBoxBkgColor": "#21262d", "labelBoxBorderColor": "#8b949e", "labelTextColor": "#e6edf3", "loopTextColor": "#e6edf3", "activationBkgColor": "#30363d", "activationBorderColor": "#8b949e"}}}%%
flowchart TD
    A[Clone repo with --recursive] --> B[Install system deps\napt-get: build-essential cmake\ncuda-toolkit llvm-dev etc]
    B --> C[Install cuDNN packages\nwith pinned versions]
    C --> D[Set up CUDA env vars\nin ~/.bashrc via quoted heredoc]
    D --> E[Create Python venv\nvirtualenv venv]
    E --> F[pip install -r requirements.txt]
    F --> G[pip install setuptools wheel numpy torch]
    G --> H[pip install test packages\ntvm-ffi pytest transformers etc]
    H --> I[pip install --no-build-isolation\ntransformer_engine pytorch]
    I --> J{Building in Docker?}
    J -- Yes --> K[Export TORCH_CUDA_ARCH_LIST]
    J -- No --> L[Build nvFuser\npip install --no-build-isolation -e python]
    K --> L
    L --> M[Verify: import nvfuser_direct as nvfuser]

Loading

_{Reviews (5): Last reviewed commit: "README: add more dependencies for runnin..." | Re-trigger Greptile}

[kevinstephano]

Looks good to me.

[zasdfgbnm]

!build

[nvswarren]

It looks like the nvfuser-ci job failed/hung.

[nvswarren]

I added some more notes re: running tests, since the CI failed for the previous push anyway. Even if CI continues to fail, at least these notes will be recorded in this PR, so people may be able to find them:-)

[greptile-apps]

The trailing backslash on the transformers line causes shell line continuation, so the second pip install and its arguments are concatenated onto the first command. The shell sees one long command: pip install apache-tvm-ffi ... transformers pip install --no-build-isolation transformer_engine[pytorch], which passes the literal strings pip, install, and --no-build-isolation as package names — the transformer_engine installation never runs as a separate command.

Suggested change

	thunder \
	transformers \
	pip install \
	--no-build-isolation transformer_engine[pytorch]
	thunder \
	transformers
	pip install \
	--no-build-isolation transformer_engine[pytorch]

[zasdfgbnm]

!test