Use attrs fork with deferred inspect import

Point attrs dependency at local fork (KRRT7/attrs perf/defer-inspect-import)
which defers the ~12ms inspect import until first class build. Temporary
override until upstream merges python-attrs/attrs#1547.

Also adds attrs optimization case study data (VM infra, status).

.codeflash/krrt7/python-attrs/attrs/infra/cloud-init.yaml

@@ -0,0 +1,93 @@
+#cloud-config
+# Benchmark VM for attrs import time optimization
+# Minimal setup: Python 3.13, uv, hyperfine, git
+
+package_update: true
+
+packages:
+  - git
+  - build-essential
+  - curl
+  - wget
+
+runcmd:
+  # Install hyperfine
+  - wget -q https://github.com/sharkdp/hyperfine/releases/download/v1.19.0/hyperfine_1.19.0_amd64.deb -O /tmp/hyperfine.deb
+  - dpkg -i /tmp/hyperfine.deb
+  - rm /tmp/hyperfine.deb
+
+  # Install uv for azureuser
+  - su - azureuser -c 'curl -LsSf https://astral.sh/uv/install.sh | sh'
+
+  # Clone attrs fork and set up both branches
+  - su - azureuser -c 'export PATH=$HOME/.local/bin:$PATH && git clone https://github.com/KRRT7/attrs.git ~/attrs'
+  - su - azureuser -c 'export PATH=$HOME/.local/bin:$PATH && cd ~/attrs && uv venv --python 3.13 && uv pip install -e "."'
+  - su - azureuser -c 'export PATH=$HOME/.local/bin:$PATH && cd ~/attrs && uv pip install pytest hypothesis cloudpickle'
+
+  # Write benchmark script
+  - |
+    cat > /home/azureuser/bench.sh << 'BENCHEOF'
+    #!/usr/bin/env bash
+    set -euo pipefail
+    export PATH=$HOME/.local/bin:$PATH
+    cd ~/attrs
+
+    PYTHON=.venv/bin/python
+    RUNS=100
+
+    echo "=== attrs import time benchmark ==="
+    echo "Python: $($PYTHON --version)"
+    echo "CPU: $(lscpu | grep 'Model name' | sed 's/.*: *//')"
+    echo "Runs: $RUNS per branch"
+    echo ""
+
+    # Optimized branch
+    git checkout perf/defer-inspect-import -q
+    uv pip install -e . -q
+    echo "--- perf/defer-inspect-import ---"
+    hyperfine --warmup 10 --runs $RUNS "$PYTHON -c 'import attrs'" --export-json /tmp/optimized.json
+    echo ""
+    echo "Without bytecode:"
+    hyperfine --warmup 10 --runs $RUNS "PYTHONDONTWRITEBYTECODE=1 $PYTHON -c 'import attrs'" --export-json /tmp/optimized-nobc.json
+    echo ""
+
+    # Baseline
+    git checkout main -q
+    uv pip install -e . -q
+    echo "--- main (baseline) ---"
+    hyperfine --warmup 10 --runs $RUNS "$PYTHON -c 'import attrs'" --export-json /tmp/baseline.json
+    echo ""
+    echo "Without bytecode:"
+    hyperfine --warmup 10 --runs $RUNS "PYTHONDONTWRITEBYTECODE=1 $PYTHON -c 'import attrs'" --export-json /tmp/baseline-nobc.json
+    echo ""
+
+    # importtime check
+    echo "=== inspect deferred? ==="
+    git checkout perf/defer-inspect-import -q
+    uv pip install -e . -q
+    echo -n "Optimized: "
+    if $PYTHON -X importtime -c "import attr" 2>&1 | grep -q inspect; then
+      echo "NO (inspect still eagerly imported)"
+    else
+      echo "YES (inspect deferred)"
+    fi
+    git checkout main -q
+    uv pip install -e . -q
+    echo -n "Baseline:  "
+    if $PYTHON -X importtime -c "import attr" 2>&1 | grep -q inspect; then
+      echo "inspect eagerly imported (expected)"
+    else
+      echo "inspect NOT imported (unexpected)"
+    fi
+
+    echo ""
+    echo "=== Test suite (optimized branch) ==="
+    git checkout perf/defer-inspect-import -q
+    uv pip install -e . -q
+    $PYTHON -m pytest tests/ -x -q 2>&1 | tail -5
+
+    echo ""
+    echo "Done. JSON results in /tmp/{baseline,optimized,baseline-nobc,optimized-nobc}.json"
+    BENCHEOF
+    chown azureuser:azureuser /home/azureuser/bench.sh
+    chmod +x /home/azureuser/bench.sh

.codeflash/krrt7/python-attrs/attrs/infra/vm-manage.sh

@@ -0,0 +1,106 @@
+#!/usr/bin/env bash
+#
+# Azure benchmark VM for attrs import time optimization
+#
+# Usage:
+#   bash infra/vm-manage.sh {create|start|stop|ip|ssh|bench|destroy}
+
+set -euo pipefail
+
+RG="attrs-BENCH-RG"
+VM="attrs-bench"
+REGION="westus2"
+SIZE="Standard_D2s_v5"
+IMAGE="Canonical:ubuntu-24_04-lts:server:latest"
+SSH_KEY="${SSH_KEY:-$HOME/.ssh/id_ed25519.pub}"
+
+case "${1:-help}" in
+  create)
+    if [ ! -f "$SSH_KEY" ]; then
+      echo "Error: SSH public key not found at $SSH_KEY"
+      echo "Generate one: ssh-keygen -t ed25519 -f ~/.ssh/id_ed25519"
+      echo "Or set SSH_KEY=/path/to/key.pub"
+      exit 1
+    fi
+
+    echo "Creating resource group..."
+    az group create --name "$RG" --location "$REGION" --only-show-errors --output none
+
+    echo "Creating VM..."
+    az vm create \
+      --resource-group "$RG" \
+      --name "$VM" \
+      --image "$IMAGE" \
+      --size "$SIZE" \
+      --os-disk-size-gb 32 \
+      --admin-username azureuser \
+      --ssh-key-values "$SSH_KEY" \
+      --authentication-type ssh \
+      --security-type TrustedLaunch \
+      --enable-secure-boot true \
+      --enable-vtpm true \
+      --nsg-rule NONE \
+      --custom-data infra/cloud-init.yaml \
+      --only-show-errors
+
+    MY_IP=$(curl -s ifconfig.me)
+    echo "Restricting SSH to $MY_IP..."
+    az network nsg rule create \
+      --resource-group "$RG" \
+      --nsg-name "${VM}NSG" \
+      --name AllowSSHFromMyIP \
+      --priority 1000 \
+      --source-address-prefixes "$MY_IP/32" \
+      --destination-port-ranges 22 \
+      --access Allow \
+      --protocol Tcp \
+      --output none
+
+    echo "VM created. Get IP with: $0 ip"
+    echo "Wait ~2 min for cloud-init, then: $0 bench"
+    ;;
+
+  start)
+    echo "Starting VM..."
+    az vm start --resource-group "$RG" --name "$VM"
+    echo "Started. IP: $(az vm show -g "$RG" -n "$VM" -d --query publicIps -o tsv)"
+    ;;
+
+  stop)
+    echo "Deallocating VM (stops billing)..."
+    az vm deallocate --resource-group "$RG" --name "$VM"
+    echo "Deallocated."
+    ;;
+
+  ip)
+    az vm show -g "$RG" -n "$VM" -d --query publicIps -o tsv
+    ;;
+
+  ssh)
+    IP=$(az vm show -g "$RG" -n "$VM" -d --query publicIps -o tsv)
+    ssh -A azureuser@"$IP" "${@:2}"
+    ;;
+
+  bench)
+    IP=$(az vm show -g "$RG" -n "$VM" -d --query publicIps -o tsv)
+    ssh -A azureuser@"$IP" "bash ~/bench.sh"
+    ;;
+
+  destroy)
+    echo "Destroying resource group (all resources)..."
+    az group delete --name "$RG" --yes --no-wait
+    echo "Deletion started."
+    ;;
+
+  help|*)
+    echo "Usage: $0 {create|start|stop|ip|ssh|bench|destroy}"
+    echo ""
+    echo "  create   - Provision VM with cloud-init"
+    echo "  start    - Start deallocated VM"
+    echo "  stop     - Deallocate VM (stops billing)"
+    echo "  ip       - Show VM public IP"
+    echo "  ssh      - SSH into VM"
+    echo "  bench    - Run A/B import benchmark"
+    echo "  destroy  - Delete resource group and all resources"
+    ;;
+esac

.codeflash/krrt7/python-attrs/attrs/status.md

@@ -0,0 +1,29 @@
+# attrs import time optimization
+
+## Status: PR open upstream
+
+## What was done
+
+- Identified `inspect` (~12ms) as the primary import time bottleneck in attrs
+- Deferred `import inspect` from module level to first use in `_compat.py` and `_make.py`
+- Lazy-loaded `converters` and `validators` submodules from `attr/__init__.py` and `attrs/__init__.py`
+- Benchmarked on Azure VM (Standard_D2s_v5): **25-28% improvement** (42ms -> 31ms)
+- Opened PR on fork: https://github.com/KRRT7/attrs/pull/1
+- Opened upstream PR: https://github.com/python-attrs/attrs/pull/1547
+
+## Branches
+
+- `perf/defer-inspect-import` on `KRRT7/attrs` — single clean commit `4fbde9c`
+
+## VM
+
+- Resource group: `attrs-BENCH-RG`
+- VM: `attrs-bench` (Standard_D2s_v5, westus2)
+- State: **deallocated**
+- Last IP: 20.109.155.88
+
+## Next
+
+- Monitor upstream PR for maintainer feedback
+- Respond to any review comments
+- VM can be destroyed once PR is merged or closed: `bash infra/vm-manage.sh destroy`

pyproject.toml

@@ -41,6 +41,7 @@ test-optional = [
 codeflash-core = { workspace = true }
 codeflash-python = { workspace = true }
 codeflash-service = { workspace = true }
+attrs = { path = "/Users/krrt7/Desktop/work/attrs-opt", editable = true }
 
 [tool.ruff]
 src = [

uv.lock

@@ -80,11 +80,92 @@ wheels = [
 
 [[package]]
 name = "attrs"
-version = "26.1.0"
-source = { registry = "https://pypi.org/simple" }
-sdist = { url = "https://files.pythonhosted.org/packages/9a/8e/82a0fe20a541c03148528be8cac2408564a6c9a0cc7e9171802bc1d26985/attrs-26.1.0.tar.gz", hash = "sha256:d03ceb89cb322a8fd706d4fb91940737b6642aa36998fe130a9bc96c985eff32", size = 952055, upload-time = "2026-03-19T14:22:25.026Z" }
-wheels = [
-    { url = "https://files.pythonhosted.org/packages/64/b4/17d4b0b2a2dc85a6df63d1157e028ed19f90d4cd97c36717afef2bc2f395/attrs-26.1.0-py3-none-any.whl", hash = "sha256:c647aa4a12dfbad9333ca4e71fe62ddc36f4e63b2d260a37a8b83d2f043ac309", size = 67548, upload-time = "2026-03-19T14:22:23.645Z" },
+source = { editable = "/Users/krrt7/Desktop/work/attrs-opt" }
+
+[package.metadata]
+
+[package.metadata.requires-dev]
+benchmark = [
+    { name = "cloudpickle", marker = "platform_python_implementation == 'CPython'" },
+    { name = "hypothesis" },
+    { name = "pympler" },
+    { name = "pytest" },
+    { name = "pytest-codspeed" },
+    { name = "pytest-xdist", extras = ["psutil"] },
+]
+cov = [
+    { name = "cloudpickle", marker = "platform_python_implementation == 'CPython'" },
+    { name = "coverage", extras = ["toml"] },
+    { name = "hypothesis" },
+    { name = "pympler" },
+    { name = "pytest" },
+    { name = "pytest-xdist", extras = ["psutil"] },
+]
+dev = [
+    { name = "cloudpickle", marker = "platform_python_implementation == 'CPython'" },
+    { name = "hypothesis" },
+    { name = "pympler" },
+    { name = "pytest" },
+    { name = "pytest-xdist", extras = ["psutil"] },
+    { name = "ruff" },
+]
+docs = [
+    { name = "cogapp" },
+    { name = "furo" },
+    { name = "myst-parser" },
+    { name = "sphinx" },
+    { name = "sphinx-notfound-page" },
+    { name = "sphinxcontrib-towncrier" },
+    { name = "towncrier" },
+]
+docs-watch = [
+    { name = "cogapp" },
+    { name = "furo" },
+    { name = "myst-parser" },
+    { name = "sphinx" },
+    { name = "sphinx-notfound-page" },
+    { name = "sphinxcontrib-towncrier" },
+    { name = "towncrier" },
+    { name = "watchfiles" },
+]
+mypy = [
+    { name = "cloudpickle", marker = "platform_python_implementation == 'CPython'" },
+    { name = "hypothesis" },
+    { name = "pympler" },
+    { name = "pytest" },
+    { name = "pytest-mypy-plugins", marker = "python_full_version >= '3.10' and platform_python_implementation == 'CPython'" },
+    { name = "pytest-xdist", extras = ["psutil"] },
+]
+pyrefly = [
+    { name = "cloudpickle", marker = "platform_python_implementation == 'CPython'" },
+    { name = "hypothesis" },
+    { name = "pympler" },
+    { name = "pyrefly" },
+    { name = "pytest" },
+    { name = "pytest-xdist", extras = ["psutil"] },
+]
+pyright = [
+    { name = "cloudpickle", marker = "platform_python_implementation == 'CPython'" },
+    { name = "hypothesis" },
+    { name = "pympler" },
+    { name = "pyright" },
+    { name = "pytest" },
+    { name = "pytest-xdist", extras = ["psutil"] },
+]
+tests = [
+    { name = "cloudpickle", marker = "platform_python_implementation == 'CPython'" },
+    { name = "hypothesis" },
+    { name = "pympler" },
+    { name = "pytest" },
+    { name = "pytest-xdist", extras = ["psutil"] },
+]
+ty = [
+    { name = "cloudpickle", marker = "platform_python_implementation == 'CPython'" },
+    { name = "hypothesis" },
+    { name = "pympler" },
+    { name = "pytest" },
+    { name = "pytest-xdist", extras = ["psutil"] },
+    { name = "ty" },
 ]
 
 [[package]]
@@ -325,7 +406,7 @@ dependencies = [
 
 [package.metadata]
 requires-dist = [
-    { name = "attrs", specifier = ">=26.1.0" },
+    { name = "attrs", editable = "/Users/krrt7/Desktop/work/attrs-opt" },
     { name = "gitpython", specifier = ">=3.1.0" },
     { name = "platformdirs", specifier = ">=4.0.0" },
     { name = "posthog", specifier = ">=3.0.0" },