> ## Documentation Index > Fetch the complete documentation index at: https://docs.cognite.com/llms.txt > Use this file to discover all available pages before exploring further. > ## Agent Instructions > Cognite Data Fusion (CDF) is an industrial DataOps platform. Prefer English docs unless the user asks for another locale. > Follow /_llms/ index links recursively until you reach page URLs ending in .md. Fetch those Markdown twins instead of HTML. > For REST APIs, default to calendar version 20230101 (stable). Use 20230101-beta or 20230101-alpha only if the user is on a preview API. Cite paths under /api-reference/concepts// and the Cdf-Version header. Prefer the Python SDK (cognite-sdk) unless the user is in JavaScript/TypeScript. > Start here by task: platform overview /cdf/index.md; data modeling /cdf/dm/index.md; data integration /cdf/integration/index.md; access /cdf/access/index.md; CDF Toolkit /cdf/deploy/cdf_toolkit/index.md; REST quickstart /dev/quickstart.md; Python SDK https://cognite-sdk-python.readthedocs-hosted.com/en/stable/; Atlas AI /cdf/atlas_ai/concepts/index.md; Flows apps /cdf/flows/index.md; MCP and IDE setup /dev/guides/ide_ai_integration.md. > For implementation work, also load /skill.md. # Building configurations > Validate Cognite Toolkit modules, substitute variables, and write the build directory that cdf deploy sends to CDF. This article shows how to build local YAML files and check them before you deploy them to a Cognite Data Fusion (CDF) project. Data engineers use `cdf build` while they develop configuration. Cognite Toolkit administrators use it in CI/CD to stop a deploy when the build reports errors. Authenticate first and keep a `.env` file in the directory where you run the Cognite Toolkit. See [Authenticating with the Cognite Toolkit](https://docs.cognite.com/cdf/deploy/cdf_toolkit/getting_started/auth.md). A small set of files can live directly in `build/`, which is what [Deploying configurations](https://docs.cognite.com/cdf/deploy/cdf_toolkit/getting_started/deploy.md) does. Larger projects usually have more than one CDF project, small differences between those projects, and resources that depend on each other. `cdf build` organizes the YAML files, checks those dependencies, and substitutes variables so the same modules can target each project. **1. Create a module** A module is a folder of YAML files that you deploy together. One module can hold the configuration for ingesting data from one source. In this article, you create a small data model. Create `modules/my_module/data_modeling/my.View.yaml` with the following content: ```yaml title="my.View.yaml" wrap theme={"languages":{"custom":["/_languages/kuiper.json"]}} space: my_space externalId: MyView version: v1 properties: name: container: type: container space: my_space externalId: MyContainer containerPropertyIdentifier: name ``` The directory looks like this: ```shell theme={"languages":{"custom":["/_languages/kuiper.json"]}} modules/ my_module/ data_modeling/ my.View.yaml ``` The directory name `data_modeling` and the suffix `.View.yaml` tell the Cognite Toolkit which resource type the YAML file defines. The [resource library](https://docs.cognite.com/cdf/deploy/cdf_toolkit/references/resource_library.md) lists every supported resource. **2. Build the module** Run the following command to build the module: ```shell theme={"languages":{"custom":["/_languages/kuiper.json"]}} cdf build ``` You did not specify which module to build, so the Cognite Toolkit prompts you to select one. Skip the prompt by naming the module: `cdf build --modules my_module`. ```shell title="Select module to build" theme={"languages":{"custom":["/_languages/kuiper.json"]}} $ cdf build ? Which modules would you like to build? [my_module (modules/my_module)] ``` The Cognite Toolkit loads the module and builds it. In this example it loads one module and one resource file. **3. Review the build results** The Cognite Toolkit then validates agents, data modeling, dependencies, functions, and Cognite InField configuration. If the build finds insights, the Cognite Toolkit prints them: ```shell title="Insights/issues" theme={"languages":{"custom":["/_languages/kuiper.json"]}} ╭─ Build Insights ──────────────────────────────────────────────────────────────────────────────────╮ │ │ │ ✗ Missing referenced resource [MISSING-REFERENCED-RESOURCE] │ │ ╰─ modules/my_module/data_modeling/my.View.yaml │ │ The space 'my_space' does not exist locally or in CDF. It is referenced by │ │ 'my_space:MyView(version=v1)'. │ │ → Ensure that the space exists or remove the reference to it. │ │ │ │ ✗ Missing referenced resource [MISSING-REFERENCED-RESOURCE] │ │ ╰─ modules/my_module/data_modeling/my.View.yaml:9:19 │ │ The container 'my_space:MyContainer' does not exist locally or in CDF. It is referenced by │ │ 'my_space:MyView(version=v1)'. │ │ → Ensure that the container exists or remove the reference to it. │ │ │ │ ✗ Missing referenced property [MISSING-REFERENCED-PROPERTY] │ │ ╰─ modules/my_module/data_modeling/my.View.yaml:10:34 │ │ Container property 'my_space:MyContainer.name' does not exist locally or in CDF. It is │ │ referenced by 'my_space:MyView(version=v1)'. │ │ → Ensure that the container property exists or remove the reference to it. │ │ │ │ All insights are written to build/insights.csv │ │ To ignore a rule, add '# rules: ignore[CODE]' to the file, where [CODE] is the code found above │ │ in brackets, or list the code under 'ignore' in the [rules] section of cdf.toml to ignore it in │ │ all files │ │ │ ╰───────────────────────────────────────────────────────────────────────────────────────────────────╯ ``` The build reports three insights for the view. You fix them in the **Fix insights found in the build** step. In most terminals, `modules/my_module/data_modeling/my.View.yaml:10:34` is a link that opens the file at the line and column where the insight was found. The summary reports three errors and says **Do not proceed to deploy.** The view depends on a space and a container that are missing, so the deployment would fail. **4. Fix insights found in the build** Fix the insights from the **Review the build results** step by creating the missing space and container. Create `modules/my_module/data_modeling/my.Space.yaml` with the following content: ```yaml title="my.Space.yaml" wrap theme={"languages":{"custom":["/_languages/kuiper.json"]}} space: my_space ``` and `modules/my_module/data_modeling/my.Container.yaml` with the following content: ```yaml title="my.Container.yaml" wrap theme={"languages":{"custom":["/_languages/kuiper.json"]}} space: my_space externalId: MyContainer usedFor: node properties: name: type: type: text list: false ``` The directory looks like this: ```shell theme={"languages":{"custom":["/_languages/kuiper.json"]}} modules/ my_module/ data_modeling/ my.Container.yaml my.Space.yaml my.View.yaml ``` **5. Rebuild the module** Run the following command to rebuild the module: ```shell theme={"languages":{"custom":["/_languages/kuiper.json"]}} cdf build --modules my_module ``` The build and validation match the **Review the build results** step. This time there are no insights, and the summary says **Ready to deploy.** Inspect the `build/` directory. The Cognite Toolkit has created a subdirectory for each resource type and placed the built YAML files in the corresponding subdirectory. The built YAML files match the source YAML files. **6. Create config.dev.yaml** The `space` property in the space, container, and view is hardcoded to `my_space` in all three YAML files. That is easy to get wrong when the identifier changes, or when dev and prod use different spaces. Create a `config.dev.yaml` file: ```yaml title="config.dev.yaml" wrap theme={"languages":{"custom":["/_languages/kuiper.json"]}} environment: name: dev project: my_cdf_project validation-type: dev selected: - modules/my_module variables: space: my_space ``` For more information about the `config.dev.yaml` file, see [Configuration file](https://docs.cognite.com/cdf/deploy/cdf_toolkit/api/config_yaml.md). The directory structure is now: ```shell theme={"languages":{"custom":["/_languages/kuiper.json"]}} config.dev.yaml modules/ my_module/ data_modeling/ my.Container.yaml my.Space.yaml my.View.yaml ``` In the three YAML files, replace the hardcoded `my_space` with `{{ space }}`. For example, `my.View.yaml`: ```yaml title="my.View.yaml" wrap theme={"languages":{"custom":["/_languages/kuiper.json"]}} space: {{ space }} externalId: MyView version: v1 properties: name: container: type: container space: {{ space }} externalId: MyContainer containerPropertyIdentifier: name ``` **7. Rebuild the module with config.dev.yaml** Run the following command to rebuild the module with the `config.dev.yaml` file: ```shell theme={"languages":{"custom":["/_languages/kuiper.json"]}} cdf build --config-yaml config.dev.yaml ``` The build and validation plan match the **Rebuild the module** step. In `build/`, the YAML files have `space` set to `my_space`. This command omits `--modules`. `config.dev.yaml` already lists the modules to build in `environment.selected`. If you pass `--modules`, that flag overrides `environment.selected`. ## Next steps Deploy the `build/` directory. See [Deploying configurations](https://docs.cognite.com/cdf/deploy/cdf_toolkit/getting_started/deploy.md). For every field in `config.[env].yaml`, see [Configuration file](https://docs.cognite.com/cdf/deploy/cdf_toolkit/api/config_yaml.md).