Sellable Micro‑Apps Marketplace: Requirements and Component Patterns for Rapid App Packaging

Hook — Ship features faster: marketplace-ready micro‑apps that teams can buy, embed, and trust

Building the same little UI widgets and micro workflows over and over wastes engineering time. Teams want production-ready, well-documented micro‑apps they can install and trust — with clear packaging, running demos, billing, and licensing so procurement and legal sign off quickly. This guide prescribes the exact packaging, metadata, demo, billing, licensing, and LLM‑usage requirements a modern micro‑apps marketplace should enforce in 2026.

The problem in 2026

By late 2025 the micro‑apps trend matured: AI‑assisted app creation made tiny, single‑purpose apps common, but marketplaces still face friction:

• Buyers can't quickly vet security, privacy, or long‑term maintenance guarantees.
• Integration across React, Vue, and plain HTML keeps being an engineering task.
• LLM‑backed micro‑apps raise disclosure, billing, and compliance questions.
• Marketplaces need standard metadata so search, bundling, and subscription SKUs work reliably.

Goals for a sellable micro‑apps marketplace

• Make each micro‑app drop‑in embeddable with a single snippet or package install.
• Ensure buyers can evaluate claims with runnable demos, tests, and performance data.
• Standardize pricing, billing SKU, and license metadata for procurement automation.
• Mandate explicit LLM usage disclosures and safe defaults.

High‑level requirements (quick checklist)

• Manifest: machine‑readable metadata (name, description, categories, tags, version, author, license, billing_skus, llm_usage).
• Bundle: ESM module + UMD or web component, single-file fallback, optimized and minified.
• Demo: live sandbox, interactive iframe, Storybook with examples, and a recorded screencast.
• Security: CSP, SRI, minimal permissions, dependency SBOM, and automated static analysis artifacts.
• Performance & A11Y: Lighthouse score targets, automated a11y tests, and bundle size budgets.
• Billing & Licensing: clear SKU, trial rules, licensing scheme, and license verification mechanism.
• LLM Disclosure: model provider, model version, prompt logging policy, cost/latency estimates, and opt‑out options.

Micro‑app manifest: the single source of truth

Require a JSON manifest at the repo root (e.g., microapp.manifest.json). Marketplaces should parse this for discovery, bundling, and billing automation. Example manifest structure:

{
  "name": "meeting-note-summarizer",
  "title": "Meeting Note Summarizer",
  "version": "1.3.0",
  "description": "Lightweight tool to capture and summarize meeting notes",
  "author": { "name": "Acme Labs", "url": "https://acme.example" },
  "categories": ["productivity","notes"],
  "tags": ["summary","ai","meeting"],
  "entry": {
    "esm": "dist/meeting-note.js",
    "umd": "dist/meeting-note.umd.js",
    "webComponent": "dist/meeting-note.wc.js",
    "cdn": "https://cdn.example.com/meeting-note/1.3.0/meeting-note.min.js"
  },
  "demo": {
    "live": "https://demo.example.com/meeting-note",
    "sandbox": "https://stackblitz.com/..",
    "storybook": "https://storybook.example.com/meeting-note"
  },
  "license": {
    "type": "proprietary",
    "terms_url": "https://acme.example/meeting-note-terms"
  },
  "billing": {
    "sku": "acme.meeting-note.pro",
    "plans": ["free-trial","monthly","enterprise"],
    "trial_days": 14
  },
  "llm_usage": {
    "uses_llm": true,
    "provider": "openai",
    "models": ["gpt-4o-mini"],
    "finetuned": false,
    "prompt_policy_url": "https://acme.example/prompt-policy",
    "tokens_estimate_per_action": 400
  },
  "security": {
    "sbom": "sbom.json",
    "csp": "default-src 'self' https://api.acme.example",
    "permissions": ["network","storage"]
  }
}

Key manifest fields explained

• entry — multiple shipping artifacts: ESM (modern), UMD (fallback), and a web component artifact make integration trivial.
• demo — mandatory: live demo, sandbox link, and Storybook URL so buyers can interact before purchase.
• billing — SKU and plan list allow marketplaces to wire payments and subscriptions automatically.
• llm_usage — explicit, machine‑readable LLM disclosure used in search filters and legal review.
• security.sbom — a Software BOM (CycloneDX or SPDX) is required for faster security auditing.

Packaging patterns for compatibility and minimal friction

Micro‑apps must be usable in several host environments. Provide at least these packaging outputs:

• ESM bundle (preferred for modern apps). Publish with exports and tree‑shaking friendly code.
• Web component — ships as a custom element for framework-agnostic embedding.
• Framework wrappers — lightweight adapters for React, Vue, and Svelte (optional but recommended).
• Single script UMD — for legacy apps and simple