> ## Documentation Index
> Fetch the complete documentation index at: https://docs.nimbusbci.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Nimbus BCI Engine

> Production-ready Bayesian BCI inference in Python and Julia with real-time streaming, uncertainty quantification, and models for motor imagery, P300, and SSVEP.

*Production-ready Bayesian BCI inference for Python and Julia.*

Nimbus provides fast probabilistic inference for brain-computer interface applications. Use it for motor imagery, P300, SSVEP, adaptive BCI, and research workflows that need confidence-aware decisions.

<img src="https://mintcdn.com/nimbus-e9e10bf8/swpeAHmpSqwCXtOt/images/hero.png?fit=max&auto=format&n=swpeAHmpSqwCXtOt&q=85&s=f6aa182ff52fe409c60579afbfa0bcbe" alt="Nimbus BCI Engine documentation" style={{ width: '100%', borderRadius: 12, marginTop: 16, marginBottom: 8 }} width="1584" height="396" data-path="images/hero.png" />

## Start Here

<CardGroup cols={3}>
  <Card title="Python SDK" icon="python" href="/python-sdk/quickstart">
    Local sklearn-compatible workflows with `nimbus-bci`.
  </Card>

  <Card title="Julia SDK" icon="code" href="/julia-sdk/quickstart">
    RxInfer-backed workflows with `NimbusSDK.jl`.
  </Card>

  <Card title="Model Selection" icon="brain" href="/model-specification">
    Choose between LDA, QDA, Softmax, Probit, and STS.
  </Card>
</CardGroup>

## Why Nimbus

<CardGroup cols={2}>
  <Card title="Why Bayesian BCI Inference" icon="scale" href="/core-concepts/why-bayesian-bci">
    Compare classical LDA, SVM, and deep learning with Nimbus — including \~10× faster online updates.
  </Card>

  <Card title="Probabilistic Outputs" icon="shield" href="/core-concepts/probabilistic-ai">
    Predictions include posterior probabilities and confidence scores.
  </Card>

  <Card title="Real-Time Inference" icon="activity" href="/inference-configuration/streaming-inference">
    Batch and streaming workflows for low-latency BCI systems.
  </Card>

  <Card title="BCI-Specific Models" icon="brain" href="/model-specification">
    Bayesian model families tuned for neural feature data.
  </Card>

  <Card title="Production Guardrails" icon="check" href="/inference-configuration/error-handling">
    Validation, quality gates, diagnostics, and deployment patterns.
  </Card>
</CardGroup>

## Models

| Model           | SDK            | Best For                                                    |
| --------------- | -------------- | ----------------------------------------------------------- |
| `NimbusLDA`     | Python + Julia | Fast baseline for well-separated CSP or bandpower features. |
| `NimbusQDA`     | Python + Julia | Overlapping classes and class-specific covariance.          |
| `NimbusSoftmax` | Python         | Multiclass nonlinear boundaries with optional JAX install.  |
| `NimbusProbit`  | Julia          | Julia-native Bayesian multinomial probit workflows.         |
| `NimbusSTS`     | Python         | Non-stationary sessions and latent-state adaptation.        |

## Core Workflow

```text theme={null}
EEG acquisition -> preprocessing -> Nimbus model -> confidence-aware action
```

Nimbus expects preprocessed features rather than raw EEG. Start with [Preprocessing Requirements](/inference-configuration/preprocessing-requirements) if you are setting up CSP, bandpower, ERP, or external tool exports.

## Documentation Map

<CardGroup cols={2}>
  <Card title="Installation And Quickstarts" icon="rocket" href="/quickstart">
    Choose Python or Julia and run first inference.
  </Card>

  <Card title="Configuration" icon="settings" href="/inference-configuration/preprocessing-requirements">
    Preprocessing, normalization, batch, streaming, and error handling.
  </Card>

  <Card title="Examples" icon="play" href="/examples/basic-examples">
    Compact recipes and higher-level application patterns.
  </Card>

  <Card title="API References" icon="book" href="/python-sdk/api-reference">
    SDK-specific functions, classes, and data structures.
  </Card>
</CardGroup>

## Common Questions

<AccordionGroup>
  <Accordion title="Do I need an API key?" icon="key">
    Python does not require an API key. Julia requires an API key to install and use the commercial core.
  </Accordion>

  <Accordion title="Can Nimbus process raw EEG?" icon="activity">
    No. Nimbus expects features produced by preprocessing pipelines such as CSP, bandpower, or ERP extraction.
  </Accordion>

  <Accordion title="Which SDK should I start with?" icon="arrow-right">
    Use Python for sklearn/MNE workflows and local development. Use Julia for RxInfer-backed workflows and Julia-native model tooling.
  </Accordion>
</AccordionGroup>

## Next Read

<CardGroup cols={3}>
  <Card title="Python Quickstart" icon="python" href="/python-sdk/quickstart" />

  <Card title="Julia Quickstart" icon="code" href="/julia-sdk/quickstart" />

  <Card title="Model Specification" icon="brain" href="/model-specification" />
</CardGroup>
