Opper AI: a Stockholm gateway to EU-hosted models, set up step by step

Who is Opper AI a good fit for?

Opper suits firms that want one Swedish account for many open models, with a rule that keeps every call on EU routes.

Opper is a Stockholm company that runs a model gateway: one API key, many models, from many hosts. Not every host is in the EU, so the choice of model route matters. In Locul, the Opper models are ones hosted by TensorX (Ireland and Finland) and Lyceum (Germany), both inside the EU.

"With an EU-only model access rule, model calls run only on EU routes"

Opper docs, Security

"Opper never uses customer data to train models, and never shares it with providers for training."

Opper docs, Security

On the Gateway plan, Opper says it stores no prompts or outputs, only usage metadata. Its main production systems run in AWS Stockholm (eu-north-1), with a second site at evroc in Stockholm.

How do I get an Opper API key?

Sign in to the Opper platform, add credit, then create a key under Settings > API keys.

1. Sign in

   Go to platform.opper.ai and sign in or create an account.

2. Add credit

   Open Billing and add credit before the first call, otherwise the key works but every request is refused.

3. Set the EU-only rule

   In your organisation's model access settings, turn on the EU-only rule so no model outside the EU can be called with your keys, even by mistake.

4. Create the key

   Open Settings > API keys, create a key and name it, for example "Locul, Elin's Mac". Copy it into Locul or your password manager.

What is the Opper base URL?

The OpenAI-compatible base URL is https://api.opper.ai/v3/compat, served from Stockholm.

Test your key before you open Locul:

# paste your key into the variable first, never into a shared file
$ export OPPER_API_KEY="paste-your-key-here"
$ curl https://api.opper.ai/v3/compat/chat/completions \
    -H "Authorization: Bearer $OPPER_API_KEY" \
    -H 'Content-Type: application/json' \
    -d '{"model":"tensorx/deepseek/deepseek-v4-pro","messages":[{"role":"user","content":"Reply with one word: ready"}]}'

A working key returns JSON with a choices list:

{"object":"chat.completion","model":"tensorx/deepseek/deepseek-v4-pro",
 "choices":[{"index":0,"message":{"role":"assistant","content":"Ready"},"finish_reason":"stop"}],
 "usage":{...}}

Which Opper model should I pick in Locul?

Pick DeepSeek V4 Pro on TensorX: a strong open model on an EU route with zero data retention at the host.

How do I add Opper to Locul?

Open Settings > Model > Open models, pick Opper under In your region, paste the key and press Test.

1. Open Settings, then Model

   In the Locul desktop app, open Settings and choose Model.

2. Choose Open models

   Pick Open models (marked Recommended), then find Opper under In your country. Each row shows where the provider runs and whether it trains on your data.

3. Pick the model

   Under Model, choose DeepSeek V4 Pro (TensorX). Locul tags it Recommended.

4. Paste the key

   Under Access key, paste the key into the field and press Save and test. The Get a key link opens the right page at Opper if you have not made one yet.

5. Run the connection check

   Under Connection check, press Test. Ready means chat and tools both work. Ready with limits means the model can chat but could not use tools in the check, so pick another model for bots that read files.

Why does the Opper connection check fail?

Usually because there is no credit on the account yet, or the EU-only rule blocks the model you picked.

What does a real request on Opper look like?

A messy, everyday job with client names in it, the kind of work this setup is for.

Here is a request an associate at a Stockholm law firm might send to a Locul bot running on Opper:

Opper's gateway in Stockholm sends the lease only to EU-hosted model routes, and keeps usage metadata only.

How fast and how good is Opper in Locul?

We are timing real office tasks on Opper with the recommended model, and the results will be published here.

What other in-country providers work with Locul?

Five more EU and Swiss providers, each with its own guide.

Frequently asked questions

Other setup paths