# Building a Llama Stack Distribution

This guide will walk you through the steps to get started with building a Llama Stack distributiom from scratch with your choice of API providers. Please see the [Getting Started Guide](./getting_started.md) if you just want the basic steps to start a Llama Stack distribution.

## Step 1. Build
In the following steps, imagine we'll be working with a `Meta-Llama3.1-8B-Instruct` model. We will name our build `8b-instruct` to help us remember the config. We will start build our distribution (in the form of a Conda environment, or Docker image). In this step, we will specify:
- `name`: the name for our distribution (e.g. `8b-instruct`)
- `image_type`: our build image type (`conda | docker`)
- `distribution_spec`: our distribution specs for specifying API providers
  - `description`: a short description of the configurations for the distribution
  - `providers`: specifies the underlying implementation for serving each API endpoint
  - `image_type`: `conda` | `docker` to specify whether to build the distribution in the form of Docker image or Conda environment.


At the end of build command, we will generate `<name>-build.yaml` file storing the build configurations.

After this step is complete, a file named `<name>-build.yaml` will be generated and saved at the output file path specified at the end of the command.

#### Building from scratch
- For a new user, we could start off with running `llama stack build` which will allow you to a interactively enter wizard where you will be prompted to enter build configurations.
```
llama stack build
```

Running the command above will allow you to fill in the configuration to build your Llama Stack distribution, you will see the following outputs.

```
> Enter an unique name for identifying your Llama Stack build distribution (e.g. my-local-stack): 8b-instruct
> Enter the image type you want your distribution to be built with (docker or conda): conda

 Llama Stack is composed of several APIs working together. Let's configure the providers (implementations) you want to use for these APIs.
> Enter the API provider for the inference API: (default=meta-reference): meta-reference
> Enter the API provider for the safety API: (default=meta-reference): meta-reference
> Enter the API provider for the agents API: (default=meta-reference): meta-reference
> Enter the API provider for the memory API: (default=meta-reference): meta-reference
> Enter the API provider for the telemetry API: (default=meta-reference): meta-reference

 > (Optional) Enter a short description for your Llama Stack distribution:

Build spec configuration saved at ~/.conda/envs/llamastack-my-local-llama-stack/8b-instruct-build.yaml
```

**Ollama (optional)**

If you plan to use Ollama for inference, you'll need to install the server [via these instructions](https://ollama.com/download).


#### Building from templates
- To build from alternative API providers, we provide distribution templates for users to get started building a distribution backed by different providers.

The following command will allow you to see the available templates and their corresponding providers.
```
llama stack build --list-templates
```

![alt text](resources/list-templates.png)

You may then pick a template to build your distribution with providers fitted to your liking.

```
llama stack build --template tgi
```

```
$ llama stack build --template tgi
...
...
Build spec configuration saved at ~/.conda/envs/llamastack-tgi/tgi-build.yaml
You may now run `llama stack configure tgi` or `llama stack configure ~/.conda/envs/llamastack-tgi/tgi-build.yaml`
```

#### Building from config file
- In addition to templates, you may customize the build to your liking through editing config files and build from config files with the following command.

- The config file will be of contents like the ones in `llama_stack/distributions/templates/`.

```
$ cat llama_stack/templates/ollama/build.yaml

name: ollama
distribution_spec:
  description: Like local, but use ollama for running LLM inference
  providers:
    inference: remote::ollama
    memory: meta-reference
    safety: meta-reference
    agents: meta-reference
    telemetry: meta-reference
image_type: conda
```

```
llama stack build --config llama_stack/templates/ollama/build.yaml
```

#### How to build distribution with Docker image

> [!TIP]
> Podman is supported as an alternative to Docker. Set `DOCKER_BINARY` to `podman` in your environment to use Podman.

To build a docker image, you may start off from a template and use the `--image-type docker` flag to specify `docker` as the build image type.

```
llama stack build --template local --image-type docker
```

Alternatively, you may use a config file and set `image_type` to `docker` in our `<name>-build.yaml` file, and run `llama stack build <name>-build.yaml`. The `<name>-build.yaml` will be of contents like:

```
name: local-docker-example
distribution_spec:
  description: Use code from `llama_stack` itself to serve all llama stack APIs
  docker_image: null
  providers:
    inference: meta-reference
    memory: meta-reference-faiss
    safety: meta-reference
    agentic_system: meta-reference
    telemetry: console
image_type: docker
```

The following command allows you to build a Docker image with the name `<name>`
```
llama stack build --config <name>-build.yaml

Dockerfile created successfully in /tmp/tmp.I0ifS2c46A/DockerfileFROM python:3.10-slim
WORKDIR /app
...
...
You can run it with: podman run -p 8000:8000 llamastack-docker-local
Build spec configuration saved at ~/.llama/distributions/docker/docker-local-build.yaml
```


## Step 2. Configure
After our distribution is built (either in form of docker or conda environment), we will run the following command to
```
llama stack configure [ <docker-image-name> | <path/to/name.build.yaml>]
```
- For `conda` environments: <path/to/name.build.yaml> would be the generated build spec saved from Step 1.
- For `docker` images downloaded from Dockerhub, you could also use <docker-image-name> as the argument.
   - Run `docker images` to check list of available images on your machine.

```
$ llama stack configure tgi

Configuring API: inference (meta-reference)
Enter value for model (existing: Meta-Llama3.1-8B-Instruct) (required):
Enter value for quantization (optional):
Enter value for torch_seed (optional):
Enter value for max_seq_len (existing: 4096) (required):
Enter value for max_batch_size (existing: 1) (required):

Configuring API: memory (meta-reference-faiss)

Configuring API: safety (meta-reference)
Do you want to configure llama_guard_shield? (y/n): y
Entering sub-configuration for llama_guard_shield:
Enter value for model (default: Llama-Guard-3-1B) (required):
Enter value for excluded_categories (default: []) (required):
Enter value for disable_input_check (default: False) (required):
Enter value for disable_output_check (default: False) (required):
Do you want to configure prompt_guard_shield? (y/n): y
Entering sub-configuration for prompt_guard_shield:
Enter value for model (default: Prompt-Guard-86M) (required):

Configuring API: agentic_system (meta-reference)
Enter value for brave_search_api_key (optional):
Enter value for bing_search_api_key (optional):
Enter value for wolfram_api_key (optional):

Configuring API: telemetry (console)

YAML configuration has been written to ~/.llama/builds/conda/tgi-run.yaml
```

After this step is successful, you should be able to find a run configuration spec in `~/.llama/builds/conda/tgi-run.yaml` with the following contents. You may edit this file to change the settings.

As you can see, we did basic configuration above and configured:
- inference to run on model `Meta-Llama3.1-8B-Instruct` (obtained from `llama model list`)
- Llama Guard safety shield with model `Llama-Guard-3-1B`
- Prompt Guard safety shield with model `Prompt-Guard-86M`

For how these configurations are stored as yaml, checkout the file printed at the end of the configuration.

Note that all configurations as well as models are stored in `~/.llama`


## Step 3. Run
Now, let's start the Llama Stack Distribution Server. You will need the YAML configuration file which was written out at the end by the `llama stack configure` step.

```
llama stack run 8b-instruct
```

You should see the Llama Stack server start and print the APIs that it is supporting

```
$ llama stack run 8b-instruct

> initializing model parallel with size 1
> initializing ddp with size 1
> initializing pipeline with size 1
Loaded in 19.28 seconds
NCCL version 2.20.5+cuda12.4
Finished model load YES READY
Serving POST /inference/batch_chat_completion
Serving POST /inference/batch_completion
Serving POST /inference/chat_completion
Serving POST /inference/completion
Serving POST /safety/run_shield
Serving POST /agentic_system/memory_bank/attach
Serving POST /agentic_system/create
Serving POST /agentic_system/session/create
Serving POST /agentic_system/turn/create
Serving POST /agentic_system/delete
Serving POST /agentic_system/session/delete
Serving POST /agentic_system/memory_bank/detach
Serving POST /agentic_system/session/get
Serving POST /agentic_system/step/get
Serving POST /agentic_system/turn/get
Listening on :::5000
INFO:     Started server process [453333]
INFO:     Waiting for application startup.
INFO:     Application startup complete.
INFO:     Uvicorn running on http://[::]:5000 (Press CTRL+C to quit)
```

> [!NOTE]
> Configuration is in `~/.llama/builds/local/conda/tgi-run.yaml`. Feel free to increase `max_seq_len`.

> [!IMPORTANT]
> The "local" distribution inference server currently only supports CUDA. It will not work on Apple Silicon machines.

> [!TIP]
> You might need to use the flag `--disable-ipv6` to  Disable IPv6 support

This server is running a Llama model locally.

## Step 4. Test with Client
Once the server is setup, we can test it with a client to see the example outputs.
```
cd /path/to/llama-stack
conda activate <env>  # any environment containing the llama-stack pip package will work

python -m llama_stack.apis.inference.client localhost 5000
```

This will run the chat completion client and query the distribution’s /inference/chat_completion API.

Here is an example output:
```
User>hello world, write me a 2 sentence poem about the moon
Assistant> Here's a 2-sentence poem about the moon:

The moon glows softly in the midnight sky,
A beacon of wonder, as it passes by.
```

Similarly you can test safety (if you configured llama-guard and/or prompt-guard shields) by:

```
python -m llama_stack.apis.safety.client localhost 5000
```


Check out our client SDKs for connecting to Llama Stack server in your preferred language, you can choose from [python](https://github.com/meta-llama/llama-stack-client-python), [node](https://github.com/meta-llama/llama-stack-client-node), [swift](https://github.com/meta-llama/llama-stack-client-swift), and [kotlin](https://github.com/meta-llama/llama-stack-client-kotlin) programming languages to quickly build your applications.

You can find more example scripts with client SDKs to talk with the Llama Stack server in our [llama-stack-apps](https://github.com/meta-llama/llama-stack-apps/tree/main/examples) repo.