Module Marketplace

What is the marketplace?

The Cosmictron module marketplace is a registry of WASM capability modules — pre-built, auditable, installable components that extend your agent’s capabilities without writing code from scratch.

Examples of marketplace modules:

• cosmictron/email-sender — send emails via SMTP/SES from a reducer
• cosmictron/pdf-extractor — extract text from uploaded PDFs
• cosmictron/stripe-payments — accept payments from agent workflows
• Third-party modules published by the community or ISVs

Module anatomy

A marketplace module is:

• A compiled WASM binary (.wasm)
• A capability manifest (manifest.json) declaring required host permissions
• A schema fragment — tables and reducers it contributes to your database
• A version tag and SHA-256 digest for integrity verification

Installing a module

# Browse available modules
cosmictron-cli marketplace search email

# Install a specific version
cosmictron-cli marketplace install cosmictron/email-sender@1.2.0

# List installed modules
cosmictron-cli marketplace list

Installation downloads the WASM binary, verifies its SHA-256 digest against the registry, and deploys it to your running instance.

Publishing a module

Any developer can publish to the marketplace. Requirements:

1. Your WASM module passes the ABI compatibility check
2. You declare a capability manifest (no undeclared host function calls)
3. You sign the release with your developer key

# Package your module
cosmictron-cli marketplace pack --name my-module --version 1.0.0

# Publish (requires authenticated marketplace account)
cosmictron-cli marketplace publish my-module-1.0.0.tar.gz

Caution

The marketplace infrastructure is live but the public registry is in beta. Expect API changes before v1 stability.

Revenue sharing

Cosmictron takes a platform fee on paid marketplace modules. Pricing and fee structure are set by the publisher. The platform fee structure is documented in the commercial license agreement.

Capability manifest

The manifest declares what host functions the module uses:

{
  "name": "cosmictron/email-sender",
  "version": "1.2.0",
  "capabilities": [
    "datastore:read",
    "datastore:write",
    "http_outbound:smtp.example.com"
  ],
  "tables": [
    {
      "name": "email_queue",
      "schema": "..."
    }
  ]
}

The server enforces the manifest — a module cannot call host functions not listed in its manifest, even if those functions exist in the ABI.

Security model

• Each module runs in its own sandboxed WASM instance — it cannot access another module’s memory
• Fuel metering caps CPU budget per invocation
• Memory limits are enforced by Wasmtime
• Marketplace modules are subject to the same row-level security as your own code
• All marketplace module installs are logged in the event log (subject to audit signing if enabled)