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

# Data model and build order

> Shared Speckle data concepts and a suggested development sequence for any connectivity architecture.

Applies to every architecture in this section. For full detail see [Data schema](/developers/data-schema/overview).

Before the steps below, decide **publish only** or **publish and load** for your host (receive-only is rare—mainly consumption apps like Power BI). See [Publish & load](/developers/connectivity/integration-depth) for integration depth.

## Projects, models, and versions

* **Project** — groups work for a team or deliverable
* **Model** — logical dataset (often per discipline or file)
* **Version** — immutable snapshot after a send; design send, receive, and automation around versions

[Workspaces and projects](/workspaces/projects) · API: [Project](/developers/sdks/python/api-reference/resources/project) · [Model](/developers/sdks/python/api-reference/resources/model) · [Version](/developers/sdks/python/api-reference/resources/version)

## Extraction, conversion, serialization, transport

Speckle exchanges **objects** in a **directed acyclic graph**, not opaque files:

1. **Extraction** — read native entities or files
2. **Conversion** — map to Speckle types and metadata
3. **Serialization** — build the graph (collections, proxies)
4. **Transport** — authenticate, send, create a **version**

## Semantic data, geometry, and display values

* **Semantic data** — [Object schema](/developers/data-schema/object-schema)
* **Geometry** — [Geometry schema](/developers/data-schema/geometry-schema)
* **Display values** — packaging for the [Viewer](/developers/viewer/introduction); see [Display values](/developers/sdks/python/concepts/display-values)

Populate semantic fields and `displayValue` (or equivalent) so viewers and downstream tools stay aligned.

## Suggested build order

Skip steps that do not apply (for example receive-only integrations).

<Steps>
  <Step title="Authentication">
    PAT, OAuth2, or app credentials — [Authentication](/developers/authentication/introduction).
  </Step>

  <Step title="Minimal object send">
    Create a project and model, send a trivial graph, confirm a **version** in the web app. [Python quickstart](/developers/sdks/python/getting-started/quickstart) or [Object Sender](/developers/packages/objectsender).
  </Step>

  <Step title="Metadata mapping">
    Stable properties and `applicationId` before scaling geometry.
  </Step>

  <Step title="Geometry extraction">
    Convert primitives your consumers need — [Geometry schema](/developers/data-schema/geometry-schema).
  </Step>

  <Step title="Incremental updates">
    Define change sets (selection, delta, full resend) and version relationships for sync.
  </Step>

  <Step title="Performance">
    Batch and deduplicate — [Optimise complexity](/developers/sdks/python/guides/how-to-optimize-and-handle-complexity).
  </Step>

  <Step title="Receive and update">
    Bidirectional flows: study receive paths in [speckle-sharp-connectors](https://github.com/specklesystems/speckle-sharp-connectors).
  </Step>

  <Step title="Deployment">
    Installers, logging, updates — [Manual installation](/connectors/manual-installation/introduction) for .NET connector patterns.
  </Step>
</Steps>

## Architectures

<CardGroup cols={2}>
  <Card title="Publish & load" icon="arrow-up-down" href="/developers/connectivity/integration-depth">
    Publish/load direction and integration depth.
  </Card>

  <Card title="Desktop host" icon="desktop" href="/developers/connectivity/desktop-host">
    Host add-ins and native desktop agents.
  </Card>

  <Card title="Cloud & automation" icon="cloud" href="/developers/connectivity/cloud-automation">
    ETL, orchestration, and version-driven jobs.
  </Card>

  <Card title="Middleware" icon="shuffle" href="/developers/connectivity/middleware">
    Enterprise orchestration between Speckle and other systems.
  </Card>

  <Card title="Hybrid" icon="layers" href="/developers/connectivity/hybrid">
    Multi-tier publish and consume patterns.
  </Card>
</CardGroup>