kumiko.rocksbeta
Why KumikoExamplesProductUpdatesLearnTrustDocsGet started
TypeScript · Bun · Postgres · MIT

You describe the domain.Kumiko gives you the backend.

Schema, auth, roles, audit log, multi-tenancy and realtime updates as TypeScript code. You only write what makes your application different.

$ bun create kumiko-app my-app
Read the docs →See examples →

Live today: publicstatus.eu, offlot.app, cashcolt.kumiko.rocks · Code and data exportable, self-hostable

New to Kumiko? Build your first real app → the Show Pony tutorial

complaints.plant-a.internal

Tenant

Plant A · Tier 2

8D report · batch 44-912

D4 completedD5 open
features/complaint.tsTypeScript
defineFeature({
  name: "complaint",
  entities: ["Report", "Action"],
  roles: ["quality", "supplier"],
  audit: "event-sourced",
})
Live on the web
publicstatus.eumulti-tenant in production
offlot.appAI campaigns
cashcolt.kumiko.rockscredit calculator
kumiko.rocksthis site

Featured build · built with Kumiko

Offlot: AI inside a real business workflow.

Offlot connects VIN-photo reading, number-plate detection and channel-specific copy generation to a complete used-car workflow: vehicles, campaigns, calendar, public vehicle pages and leads.

The workflow

VIN
Vehicle data
AI copy
Campaign
Leads
See the Offlot build →
offlot · Campaign composer
Offlot campaign composer: a campaign for a Škoda Octavia with AI-generated posts for AutoTrader, Instagram and WhatsApp, approved per post

3

AI pipeline steps

21

app-owned feature modules

147

test files

54

integration tests

34 days

visible repository history

Facts from the current offlot-app repository. The 34-day figure describes visible Git history, not claimed engineering effort.

Why Kumiko

Build your domain, not the foundations again.

Kumiko already covers the hard parts of business software: tenants, sign-in, permissions, files, search and change history. Your time goes into the logic that makes your app yours.

Live today

Proven in production.

PublicStatus, Offlot and CashColt run on the same packages you install from npm. Multi-tenant, with real users.

See the live showcases →

Developer flow

One feature definition, the whole backend.

defineFeature and createEntity describe entities, access rules and screens. Tables, handlers, validation and a CRUD UI follow from that, with strict types throughout.

Start the tutorial →

Hosting posture

Your data stays under your control.

Run your application on your own server, at a host of your choice or in your own cluster. You choose the AI models and providers that meet your requirements.

How multi-tenancy works →

Lock-in posture

No black box.

You can export code and data, the framework is public on GitHub and npm. Upgrades ship with migration notes and codemods via bunx kumiko-upgrade.

Lean operations

Modern software without unnecessary weight.

Kumiko uses TypeScript, Bun and Postgres instead of a heavy enterprise stack. Your application gets the building blocks it needs, not an oversized infrastructure.

See the technical foundation →

Is Kumiko the right fit?

Kumiko works best for multi-user business software where data, permissions and traceability matter.

Good fit

  • ●Teams building internal tools, customer portals or B2B SaaS in TypeScript.
  • ●Applications that need tenants, roles and an audit trail from day one.
  • ●Developers who want to own their code and run it themselves.

Probably not a fit

  • ●Consumer apps or products optimized mainly for growth loops, app-store UX, or high-volume public traffic.
  • ●Extreme realtime, edge, or hyperscale infrastructure problems as the central requirement.
  • ●Teams looking for a no-code tool without writing any code.
kumiko.rocks · this site, home of the framework
publicstatus.eu · multi-tenant production traffic
cashcolt.kumiko.rocks · multi-tenant credit planner
offlot.app · MVP, AI campaigns for car dealers
@marc on X · Build-stream weekly

Updates

What we're building and what we're learning

All updates →
Ship

Kumiko 0.413 brings the helpdesk: contact form and inbox

The new helpdesk feature takes questions, contact requests and problem reports from the website and from inside the app. The app's SystemAdmins get a mail without personal data and answer from an inbox of their own.

Ship

Kumiko 0.412: webhook contracts and generated HTTP API docs

Apps declare which events leave the system as webhooks, and personal access token scopes release them. kumiko api-docs writes the HTTP API reference and an OpenAPI 3.1 file from the same registry, and fails in CI when the docs fall behind the code.

Ship

Kumiko 0.407: inactive accounts get warned, then deleted

The opt-in feature tenant-inactivity mails the owners of an unused account before a deadline, for example 30 and 7 days ahead, and then files the regular deletion request with its waiting period. Data under a retention period stays until that period ends.

Showcases · built with Kumiko

Real products and AI-native builds

CashColt, PublicStatus and Offlot show three different strengths of Kumiko: domain-heavy product logic, a multi-tenant SaaS and AI steps embedded in a real business workflow.

→

Showcases and product builds

Real products and product builds

Screenshots from products built end-to-end on Kumiko, including Offlot, where AI steps are embedded in a used-car campaign workflow.

Offlot campaign composer
Offlot: AI-generated posts per channel, approved one by one
CashColt portfolio dashboard
CashColt: remaining debt, monthly payment and payoff chart
CashColt credit calculator
CashColt: loan inputs, rate stress test and extra payments
PublicStatus tenant status page
PublicStatus: public status page with an active incident
PublicStatus uptime monitor
PublicStatus: uptime dashboard with availability and latency

Building something with Kumiko?

Start with bun create kumiko-app or the Show Pony tutorial. Questions go straight to the maintainer.

Read the docs →hello@kumiko.rocks →Want the app built for you? Kumiko Studio →