Sovereign FaaS: serverless hosted in France
Zerolith is a Functions-as-a-Service platform operated from France. You deploy Python or Node.js functions, they scale back to zero as soon as nobody is calling them, and you pay only for invocations and actual execution time.
What a sovereign FaaS is
A FaaS (Functions-as-a-Service) runs your functions on demand. You ship a handler; the platform handles servers, scaling up and scaling to zero. There is no instance to maintain, and nothing to pay while nothing runs.
"Sovereign" adds two constraints, on location and on dependency: the execution infrastructure sits in France, with a French host, and the service is not a resale of a non-European hyperscaler.
What stays in France
Rather than a "hosted in France" badge, here is what you can check:
- Execution infrastructure hosted by OVH SAS (Roubaix, France). The host is named in our legal notice, as French law requires.
- No third-party cookies and no external analytics: browser local storage only holds your session token and language preference.
- Fonts served from our own servers, so no request to a third-party CDN and no visitor IP handed to Google Fonts.
- A short, published subprocessor list: hosting (OVH, France), card payments (Stripe, entered on its own pages), transactional email (Mailjet).
What you pay
Billing follows actual usage: reserved memory × running time (in GB-seconds), plus a per-invocation fee. A sleeping function costs nothing, which is the whole point of scale-to-zero.
Available runtimes
Runtimes ship ready to use. Your code is injected into a generic image, and there is no per-function image build.
| Runtime | Default handler | File |
|---|---|---|
| python | main.handler | main.py |
| python313 | main.handler | main.py |
| python314 | main.handler | main.py |
| nodejs20 | main.handler | main.js |
| nodejs22 | main.handler | main.js |
| nodejs24 | main.handler | main.js |
Each image already bundles the common libraries (HTTP requests, dates, validation, YAML), so most handlers have nothing to install.
Frequently asked questions
Where do my functions run?
In France, on infrastructure hosted by OVH SAS in Roubaix. That is also where your account data and the code you deploy live.
Is my data exposed to the US CLOUD Act?
Hosting and execution are provided by a French company on French soil, outside the CLOUD Act's reach. Card payments do go through Stripe: your card details are entered on Stripe's pages and never pass through our servers.
Is the service GDPR-compliant?
The data collected, the purposes, the subprocessors, the retention periods and your rights of access, rectification and erasure are all detailed in our privacy policy. No marketing outreach, no advertising profiling.
What do you see of the code I deploy?
Function code is stored so it can be executed and returned to you. The values of your secret variables, however, only ever live in the cluster: they are never written to the database and no API can read them back.
Can I leave with my code?
Yes. Each function's source is readable at any time from the web app, the REST API or an MCP tool. The handler is ordinary Python or Node.js, with no proprietary API to rewrite.
Deploy your first function
Free credit at signup, no card required. Nothing to pay while your functions are asleep.
Get started »