source-command-deploy

name	source-command-deploy
description	Compile Python to WASM with molt and deploy to Cloudflare Workers edge

source-command-deploy

Use this skill when the user asks to run the migrated source command deploy.

Command Template

Deploy Python to Cloudflare Workers Edge

You are deploying a Python application to Cloudflare Workers via molt (Python-to-WASM compiler).

Architecture

• Python source at examples/cloudflare-demo/src/app.py is compiled to WASM
• worker.js is the WASI shim that runs the WASM binary on Workers
• The Python code receives the URL path via sys.argv[1] and query string via QUERY_STRING env var
• print() output becomes the HTTP response body
• The VFS provides /bundle (read-only assets) and /tmp (scratch space)

Steps

1. If the user provided Python code or a description of what to deploy, update examples/cloudflare-demo/src/app.py accordingly. Keep imports minimal: sys, os, math, json, random are safe.

2. Kill any stale backend daemon and compile to WASM:

pkill -f "molt-backend.*daemon" 2>/dev/null; sleep 1
MOLT_WASM_PROFILE=pure .venv/bin/python -m molt build examples/cloudflare-demo/src/app.py \
    --target wasm --stdlib-profile micro \
    --output /tmp/molt_deploy/output.wasm \
    --linked-output /tmp/molt_deploy/linked.wasm

3. Optimize the binary:

wasm-opt -Oz --enable-bulk-memory --enable-reference-types --enable-simd \
    --enable-mutable-globals --enable-sign-ext --enable-nontrapping-float-to-int \
    --enable-multivalue --no-validation --remove-unused-module-elements \
    --remove-unused-names --strip-debug --dce --vacuum \
    /tmp/molt_deploy/linked.wasm -o /tmp/molt_deploy/linked_opt.wasm

4. Report binary size:

ls -lh /tmp/molt_deploy/linked_opt.wasm
gzip -k -f /tmp/molt_deploy/linked_opt.wasm && ls -lh /tmp/molt_deploy/linked_opt.wasm.gz

5. Copy and deploy:

cp /tmp/molt_deploy/linked_opt.wasm examples/cloudflare-demo/dist/worker_linked.wasm
wrangler deploy --config examples/cloudflare-demo/wrangler.toml

6. Test the live deployment:

curl -s https://molt-python-demo.adpena.workers.dev/

7. Report results to the user:
   • Live URL
   • Binary size (raw and gzip)
   • Test output from curl

Constraints

• Do NOT modify worker.js unless the WASI shim needs updating
• Python code must not use: eval, exec, __import__, threading, raw sockets
• Keep total gzip under 3 MB (Cloudflare free tier limit)
• Available stdlib: sys, os, math, json, random, re, collections, functools, itertools, dataclasses, typing, enum