# Create a code-signing certificate
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To digitally sign firmware images, you need a code-signing certificate and private key. For testing purposes, you can create a self‐signed certificate and private key. For production environments, purchase a certificate through a well‐known certificate authority (CA).

Different platforms require different types of code-signing certificates. The following sections describe how to create code-signing certificates for different FreeRTOS-qualified platforms.

**Topics**
+ [Creating a code-signing certificate for the Texas Instruments CC3220SF-LAUNCHXL](ota-code-sign-cert-ti.md)
+ [Creating a code-signing certificate for the Espressif ESP32](ota-code-sign-cert-esp.md)
+ [Creating a code-signing certificate for the Nordic nrf52840-dk](ota-code-sign-cert-nordic.md)
+ [Creating a code-signing certificate for the FreeRTOS Windows simulator](ota-code-sign-cert-win.md)
+ [Creating a code-signing certificate for custom hardware](ota-code-sign-cert-other.md)