JUjustvugg·Jan 25, 2026Submission
Show HN:PolyMCP – from Server to WebAssembly from the Same Python Code
PolyMCP now lets you expose Python MCP (Model Context Protocol) tools in two ways from the same code:
1. Server-based MCP deployments (HTTP endpoints)
2. WebAssembly bundles that run directly in the browser
This means you can reuse the same Python functions for server workflows or client-side experiments without any code changes.
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Why it matters
• Plug-and-play: one Python function, multiple deployment options.
• Instant testing: run your tools locally in the browser or via HTTP.
• Enterprise-ready: leverage internal libraries, scripts, and APIs immediately.
• Unified interface: MCP agents call your tools the same way, regardless of server or WASM.
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Example
# Python function
def calculate_stats(numbers):
"""Return basic statistics for a list of numbers"""
return {
"count": len(numbers),
"sum": sum(numbers),
Read the rest
"mean": sum(numbers)/len(numbers)
}
# === WebAssembly MCP ===
from polymcp import expose_tools_wasm
compiler = expose_tools_wasm([calculate_stats])
compiler.compile("./wasm_output")
The same function can also be exposed via HTTP MCP endpoints without modification.
# === HTTP MCP ===
from polymcp.polymcp_toolkit import expose_tools
app = expose_tools([calculate_stats], title="Stats Tools")
# Run with: uvicorn server_mcp:app --reload
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Repo: https://github.com/poly-mcp/Polymcp
We’d love to hear how you’re using PolyMCP and feature ideas for future releases.