wasp-build

Build the UOMI WASM Agent

You are helping a developer compile their UOMI agent from Rust to WebAssembly.

What the build does

The build pipeline (npm run build → bin/build_and_run_host.sh) performs:

1. Compile Rust → WASM: cargo build --target wasm32-unknown-unknown --release inside agent-template/
2. Copy artifact: copies the .wasm file to host/src/agent_template.wasm
3. Run host: cd host && cargo run — executes the agent against the configured input

Step 1 — Verify you're in the right directory

Check you're in the project root (where package.json lives):

ls package.json agent-template/cargo.toml 2>/dev/null && echo "OK" || echo "Wrong directory — cd into your project root"

Step 2 — Run the build

npm run build

This is equivalent to:

sh ./bin/build_and_run_host.sh

Step 3 — Interpret the output

Successful build looks like:

   Compiling agent-template v0.1.0
    Finished release [optimized] target(s)
   Compiling host v0.1.0
    Finished dev [unoptimized + debuginfo] target(s)
     Running `target/debug/host`

Successful agent execution looks like:

Assistant:
<response from the LLM>

Performance Metrics:
- Time taken: 1.20s
- Tokens/second: 45
- Total tokens: 54

Troubleshooting common errors

error[E0463]: can't find crate for 'std' or wasm32 target not found

rustup target add wasm32-unknown-unknown

error: linker 'cc' not found (Linux)

sudo apt-get install build-essential

error: package not found in cargo.toml

The project name in agent-template/cargo.toml must match the directory name (underscores, not hyphens). Check:

cat agent-template/cargo.toml | grep "^name"
# Should match the directory name with - replaced by _

Connection/API errors at runtime

The host is running your WASM and calling an LLM. Check uomi.config.json:

• Is models.1.name set? (uses UOMI network — requires node-ai service)
• For local dev, set models.2 with a valid url + api_key and use call_ai_service(2, request) in your lib.rs

thread 'main' panicked in WASM

Add debug logs in your lib.rs to trace the issue:

utils::log("checkpoint 1: input read");
let input = utils::read_input();
utils::log(&format!("input length: {}", input.len()));

Logs appear in the terminal output.

After a successful build

The built WASM is at host/src/agent_template.wasm. This is the file you'll upload to IPFS when deploying.

To run interactively (multi-turn conversation), use /wasp-dev instead of npm run build.