Nixpacks can be configured via environment variables. All of these variables are prefixed with NIXPACKS_.

NIXPACKS_INSTALL_CMDOverride the install command to use
NIXPACKS_BUILD_CMDOverride the build command to use
NIXPACKS_START_CMDOverride command to run when starting the container
NIXPACKS_PKGSAdd additional Nix packages to install
NIXPACKS_APT_PKGSAdd additional Apt packages to install (comma delimited)
NIXPACKS_LIBSAdd additional Nix libraries to make available
NIXPACKS_INSTALL_CACHE_DIRSAdd additional directories to cache during the install phase
NIXPACKS_BUILD_CACHE_DIRSAdd additional directories to cache during the build phase
NIXPACKS_NO_CACHEDisable caching for the build
NIXPACKS_CONFIG_FILELocation of the Nixpacks configuration file relative to the root of the app
NIXPACKS_DEBIANEnable Debian base image, used for supporting OpenSSL 1.1