What you get
| Supabase | Gemmein | |
|---|---|---|
| Built for | Developers who want a full Postgres platform | Founders making AI products, and the AI that builds them |
| Sign-in | Many auth methods, configured per project | Sign-in codes by emailOne method, so no password database exists. Two abuse bounds hold on sign-in emails, and how many an app sends in a day is never capped. A person stays signed in on up to 10 devices and can sign one out or sign out everywhere |
| Data safety rules | Row-level security you authorPolicies you (or your AI) write: flexible, and yours to get right | Eight plain-English rules, on by defaultChosen per collection and enforced on Gemmein's servers, even when your app's code asks for the wrong thing. There is no security setting in your code to get wrong. Collections are declared in your project’s files, and a collection other people read declares its fields before anything is written. Owner approval of posts and one-choice-per-person polls are settings on the rule. The reaffirm script, which apps copy into CI, checks the safety rules on every deploy |
| Database ownership | Yours: real PostgresSQL, migrations, and the freedom to model anything | Nothing to ownRecords live in collections under the eight rules, and files follow the same rules. There is no database, policy or auth configuration to own |
| AI on your own keys | Vector storage in Postgres | Named AI tools on your own provider keyOpenAI, Anthropic, Google, Replicate, fal, ElevenLabs, Runway, Deepgram or AssemblyAI, or any OpenAI-compatible chat provider such as OpenRouter, Mistral or Groq. The key stays on the server and never reaches the browser. Native tools cover chat, image, speech, video and transcription, each carrying the access it requires, and there is no server function of your own to deploy |
| Credits | Bring your own integration | Prepaid, priced per useThe owner sets each AI tool's price in credits, per call or per 1,000 tokens, and a purchase can grant credits. A provider failure before the first output byte refunds the credits |
| Payments & access | Bring your own integration | Built in, on your own StripeSubscriptions and one-off digital products on Payment Links Gemmein makes, and the access or credits each purchase grants. Members manage their plan in a billing portal Gemmein sets up, and the restricted key holds 5 permissions, plus 2 if you sell plans: it can’t pay out, refund, or read cards. A product can also be sold through any provider whose webhooks follow a supported signing standard, via a relay, or defined before it has a way to be sold. A full refund reconciles the access that purchase granted. A partial refund leaves it standing |
| Native app purchases | Bring your own integration | App Store and Play, through RevenueCatA store purchase reaches Gemmein through RevenueCat's webhook into a relay |
| Your own model as a tool | Edge functions run on Supabase | One tool, one run, one priceRun your own trained model, pipeline or agent system on your own host, and Gemmein still handles the person, access and credits. It can be any code in any language or framework, such as a Python script, a LangGraph graph, a CrewAI crew or an n8n flow. Name a tool on provider external and Gemmein posts the run straight to your URL, signed, with no relay involved. Your server verifies the session, reads what the person holds, and grants access or spends credits through the server API |
| Background work | Edge functions you write and deploy | Relays: configuration, not codeA verified provider event, a schedule or a record change runs up to ten actions from Gemmein's own actions: fulfil or refund a product, grant or revoke access or a plan, grant credits, write a record, email the person, call your URL, or start an AI tool's run for the event's person. Schedules run from every 15 minutes to once a week. Receivers verify by standard (Standard Webhooks, Stripe’s, or a signature recipe: HMAC-SHA1, SHA-256 or SHA-512, Ed25519 or ECDSA P-256), so any sender that follows one works, and every event is logged, retried and replayable |
| Admin dashboard | A developer dashboardRaw logs, yours to query | A dashboard to run the businessOverview, Inbox, Customers, Subscriptions, Get started, Data, Payments, Domains, Site, Relays, Emails, AI, Logs, Errors and Settings. Suspend a person, sign out one of their devices or all of them, grant or revoke access, comp credits, replay a relay event, and read the activity record. In Live, a change to one customer is your approval in the browser. A change to how your business runs (products and prices, domains, email, Stripe, keys, the Live site) also asks for a code from your email. Going live is your approval, then your plan's payment. The Errors page groups your live app's refused writes into plain-English problems, each carrying the exact refusal your app was told |
| Surface | HugeSQL, functions, realtime, storage, vectors… | Narrow on purposeYour site, hosted, and the same from a browser, an Expo app or a Swift app: sign-in by emailed code, collections, files under the same rules, live lists (watch(), by polling; websockets stay refused), subscriptions and products, AI tools priced in credits, relays, email to your people from your own domain, owner alerts by email, and the admin dashboard. If it's not in the guide, it isn't built |
| Price | Free tier, then from $25/moFree tier for two projects; Pro from $25/mo, plus usage beyond its included quotas | Free to build, one plan per accountDevelopment never bills. Launch is $29, Run a business is $79 and Grow is $199 a month for the whole account — 5, 10 or 25 apps, any of which may go live; annual billing gives 2 months off |
Their side checked against Supabase's public pricing page on 25 Sep 2026. Check their site for current details. Ours comes from Gemmein's own docs.
Which to pick
Pick Supabase if…
- You want to own a databaseYou're a developer, or you have one, and you want SQL, migrations, realtime, edge functions and the freedom to model anything. That is exactly what Supabase is for.
- You need shapes Gemmein doesn't carryTeam workspaces, staff accounts, custom roles and permission lists, or social sign-in.
- You enjoy owning the security modelRow-level security done well is excellent, and it is yours to do well.
Pick Gemmein if…
- Nobody wants to build or secure the backendNo database, policies or auth configuration to own. The AI builds, you answer the business questions, and there is no rule syntax to get wrong.
- Payments matter from day oneYour payment account, your people: subscriptions, products, and the access a refund takes back, already wired.
- Your product sells AI operationsName the tool, set the access it requires and its price in credits, per call or per 1,000 tokens. Your provider key stays on the server.
- You want event handling as configurationEvery relay run is logged, retried and replayable.
- The admin side should already existCustomers, subscriptions, payments, the Inbox and the activity record are part of the product, not a panel you write later.
- Your coding agent wants a defined platform139 tools over MCP, a CLI, and a local runtime that runs the same enforcement code as Live.
Questions
Is Gemmein built on Supabase?
No. Gemmein runs its own service: what you run locally with npx gemmein dev is what runs in its cloud. The local runtime and the cloud run the same enforcement code, so what your app proves locally is what Live enforces.
Can an AI assistant run the whole setup?
Yes. The guide at docs.gemmein.com/llms.txt is written to the AI: it assesses fit first, asks the human only the business questions, builds in Development, and hands back a tested app. Your agent works with 139 tools over MCP and a CLI. The owner signs up, free, and approves the agent’s npx gemmein login in the browser when the app first syncs. Each Live action asks for its own approval. Billing starts when you go live, or earlier if you pay for your plan first.
Can Gemmein run my own code, or a scheduled job?
Gemmein runs its own relay actions and never your code. A relay starts from a verified provider event, a schedule or a record change, and can fulfil or refund a product, grant or revoke access, grant credits, write a record, email the person, or call your URL. Gemmein also runs your AI tools — chat, image, speech, transcription and video — on your own provider key, priced in credits. Your own code, model or pipeline runs on your own host behind a signed call, and your server asks Gemmein who the person is and what they hold before it acts.
Who handles VAT and sales tax?
Whoever is the seller of record. With Gemmein the payment lands in your own provider account. Through Stripe you are the seller of record. Through a Merchant of Record such as Paddle or Lemon Squeezy connected by a relay, they are, and they carry the tax filing. Both models are legitimate. Selling digital products to EU consumers can create VAT duties from the first sale, and at heavy international volume a Merchant of Record earns its cut. Most independent businesses sit under the UK's £90,000 VAT threshold and can have Stripe Tax calculate what's owed. So the real choice is whether to hand over the relationship with your people in return for paperwork you may not owe yet. Gemmein never holds, moves, or processes money either way. Your provider does that, inside your own account. Stripe is built in. Any provider whose webhooks follow a signing standard Gemmein supports drives access the same way, through a relay: Standard Webhooks, Stripe’s, or a signature recipe (HMAC-SHA1, SHA-256 or SHA-512, Ed25519 or ECDSA P-256). GoCardless, Paddle and Lemon Squeezy are among them.
What can't Gemmein do?
Gemmein is for apps with sign-in by emailed code: on the web, on iOS and Android through Expo, and on iOS and Mac through the Swift package. Social sign-in, staff accounts and team seats are not available. There are no custom roles or permission lists, no carts or physical goods, and no multi-seller payouts. Credits are prepaid, at the price the owner sets for each AI tool call. Postpaid token-based invoicing is not included. If something isn't in the builder guide, it isn't built, and the guide states its bounds so your AI doesn't invent a workaround.
Add Gemmein to your AI. Then tell it what you want.
Building is free. No card until you go live.