Install or Update an SDK#

Objective#

Install a new Software Development Kit (SDK) by using Silicon Labs Tool (SLT).

Installing an SDK#

You can install an SDK by defining package dependencies in a recipe file (recommended) or by installing a specific SDK version directly.

Install Using a Recipe File (Recommended)
The pkg.slt recipe file defines the packages and versions that your project depends on. Instead of installing each package individually, define the dependencies once in pkg.slt, and let SLT install and manage them together.
Create a file named pkg.slt:
```
version = "0"
[dependency]
simplicity-sdk = "~"version = "0"
[dependency]
simplicity-sdk = "~"
```
Note: The ~ version specifier instructs SLT to install the latest compatible version instead of an exact version.
Install a Specific SDK Version
To install a specific SDK version by using a recipe file, specify the SDK version in the pkg.slt file.
```
version = "0"
[dependency]
simplicity-sdk = "2025.6.0"version = "0"
[dependency]
simplicity-sdk = "2025.6.0"
```
You can also install a specific SDK version directly.
```
slt install simplicity-sdk/2025.12.1slt install simplicity-sdk/2025.12.1
```

Step 1. Update Package Information#

slt update -aslt update -a

This command updates installed packages.

Step 2. Install the New SDK Version#

Install a Single Package#

slt install <package-id>slt install <package-id>

Install Using a Recipe File#

slt install -f <recipe_file>.sltslt install -f <recipe_file>.slt

Step 3. Verify the Installed SDK#

slt listslt list

Additional Installation Examples#

Install the latest Simplicity SDK:

slt install simplicity-sdkslt install simplicity-sdk

Install a specific version:

slt install simplicity-sdk/2025.12.1slt install simplicity-sdk/2025.12.1

Install with the check-updates flag:

slt install simplicity-sdk/2025.12.1 --check-updatesslt install simplicity-sdk/2025.12.1 --check-updates

Install all packages from the default recipe file:
```
slt installslt install
```

Install from a custom recipe file:

slt install -f myrecipe.sltslt install -f myrecipe.slt

Install from a lock file (exact versions):

slt install -f pkg.lockslt install -f pkg.lock

Non-interactive mode for Continuous Integration/Continuous Delivery (CI/CD):

slt install -f pkg.slt --non-interactiveslt install -f pkg.slt --non-interactive

Package Installation Location#

By default, SLT installs packages in the following directories.

~/.silabs/slt/installs/
├── conan/p/        ← SDKs and SDK extensions always here
└── archive/        ← Some tools installed here~/.silabs/slt/installs/
├── conan/p/        ← SDKs and SDK extensions always here
└── archive/        ← Some tools installed here

Note: Share the generated pkg.lock file to ensure that all team members use the same package versions. This approach makes builds reproducible across CI/CD environments.