Launch HN: Vendo (YC S26) – Let users build features on top of your product

Aug 20, 2026 10:29 PM - 1 hour ago 1

 your product, shaped to each customer

An open-source customization layer.
Your users build their ain features and micro-apps, correct connected apical of your product.

Vendo is for B2B SaaS teams whose customers support asking for bespoke features. It is an embedded agent: it acts done your product's ain API arsenic the signed-in user, and renders the UI it generates successful a sandboxed, brand-native surface. Your root codification is ne'er touched. Learn much astatine vendo.run, aliases publication the docs astatine docs.vendo.run.

 vendoai  Apache-2.0  docs.vendo.run

01 · See it successful action

Every seizure beneath is simply a existent supplier tally successful a demo big app, not a mockup.

A Maple customer asks wherever their money went and the supplier composes a unrecorded spending view

Build views. Ask a question, get a unrecorded position composed from the host's ain components and API.

A Cadence personification hovers the deadlines card, asks for urgency color-coding, and applies the remix successful place

Remix the UI. Hover a component, picture the change, use it successful place.

A Cadence personification asks for a greeting document-chase automation and turns it connected pinch per-tool approvals

Automate crossed tools. Plain connection in, opinionated automation out, each instrumentality gated by approval.

02 · Install

npm instal @vendoai/vendo npx vendo init

Or instal pinch your coding agent

Claude Code, Cursor, GitHub Copilot, OpenAI Codex, Windsurf

Paste this wrong your app's repo:

Install Vendo successful this repo. Read https://vendo.run/agents.md and follow it exactly. Relay Vendo's setup questions to maine and usage my answers. Ask me before creating immoderate relationship aliases cardinal — Vendo Cloud is the recommended option. You're done erstwhile my app runs and the supplier answers from my ain API. Then inquire maine whether I'd for illustration to prima it via https://vendo.run/star?src=readme to support the project.

Done is your app moving and the supplier answering from your ain API. vendo expert is the optional checkup, and each codification it prints links to its exact fix. Full playbook: docs.vendo.run/install · Agent-readable: vendo.run/agents.md

Which 1 are you?
You already person an agent — 1 instrumentality battalion for your AI SDK, Mastra, aliases homegrown loop.
Your merchandise has nary agent — 1 bid brings the loop, the chat UI, and the approvals.
Expose your merchandise complete MCP — Claude, ChatGPT, Cursor, and Claude Code enactment arsenic the signed-in user.
Your supplier lives successful your backend — 1 package, agent() and chat(), nary CLI and nary UI of ours to mount.

03 · How it works

Vendo runs a streaming supplier pinch immoderate AI SDK LanguageModel.

1 · Extract. Vendo sounds your API and turns it into devices the supplier executes arsenic the signed-in user.

2 · Generate. The supplier composes views and user-owned apps from a format-tagged UI document, generated components tally successful an iframe jailhouse pinch connect-src 'none', escalating to a sandboxed server only erstwhile needed.

3 · Guard. Policy, approvals, grants, breakers, and audit each beryllium astatine one execution choke point; app machines scope big devices only done the guarded instrumentality proxy.

PGlite astatine .vendo/data is the zero-config store; accumulation runs the same schema connected Postgres. Full architecture: docs.vendo.run.

04 · Packages

@vendoai/vendo is the default creation (vendoai is simply a bladed alias). Install individual blocks erstwhile you want to constitute Vendo yourself.

Package One job
@vendoai/core Shared types, schemas, formats, validators, and seams
@vendoai/store Postgres persistence, pinch PGlite arsenic the default
@vendoai/harnesses The move runtime: speech loop, streaming, tools, and thread context
@vendoai/actions Host API and connector devices executed arsenic the signed-in user
@vendoai/guard Policy, approvals, grants, audit, breakers, and safety
@vendoai/apps App generation, editing, execution, interchange, and sandbox adapters
@vendoai/automations Trigger ingestion, schedules, distant runs, and tally history
@vendoai/ui Headless React hooks, optional chrome, character rendering, and the in-jail constituent kit
@vendoai/mcp The door: serves the host's devices to extracurricular MCP clients
@vendoai/telemetry Anonymous, opt-out build and improvement telemetry
@vendoai/vendo Default composition, nationalist wire, React entry, and vendo bin

Cloud-gated sharing, publishing, org overlays, and pinning activate with VENDO_API_KEY; the open-source blocks stay self-hosted.

Shaped to each customer. Star runvendo/vendo. Apache-2.0, docs.vendo.run, vendo.run, backed by Y Combinator

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