Languages & Interpreters

Ephemora Cell executes pre-compiled .wasm modules — it does not ship language interpreters. For building from source, use ephemora-cell build <source> (see the README and ADR-005); this page covers running interpreted languages inside the sandbox.

WASI Preview1

Ephemora Cell currently uses WASI Preview1 (wasi_snapshot_preview1), the stable WASI interface with:

• File I/O (fd_read, fd_write, path_open, etc.)
• Command-line arguments and environment variables
• Clock access and random data

Preview1 limitations:

• No network socket support (requires WASI Preview2 / Component Model)
• No process spawning
• Limited filesystem metadata operations
• No streaming I/O

WASI 0.2 components are already supported (opt-in via abi="component" or auto-detection — see recipes): command-world (wasi:cli/run) components run with the same security baseline as Preview1. WASI 0.3 / Preview2 network sockets remain deferred until the Component Model 1.0 spec is final (target late 2026/2027).

Using Custom Interpreters

To run Python, Rust, Go, or other languages inside the sandbox, compile the interpreter (or your application) to WASM and execute it like any module.

Python (CPython-WASI):

# Build CPython for WASI (requires WASI SDK)
git clone https://github.com/singlestore-labs/python-wasi
cd python-wasi && ./run.sh  # Produces wasi-python-3.x.wasm (~150MB)

# Use with Ephemora Cell
from ephemora_cell import run_wasm
result = run_wasm("wasi-python-3.10.wasm", args=["-c", "print('Hello')"])

Rust (wasm32-wasip1):

rustup target add wasm32-wasip1
cargo build --target wasm32-wasip1 --release

from ephemora_cell import run_wasm
result = run_wasm("target/wasm32-wasip1/release/myapp.wasm")

Go:

GOOS=wasip1 GOARCH=wasm go build -o myapp.wasm main.go

Note: Interpreter overhead (CPython: 17-140ms cold start) is not included in Ephemora Cell's performance metrics. Those measure the sandbox engine, not the guest interpreter.