Install Krill Server on Raspberry Pi

Install Krill Server on a Raspberry Pi

Please note that Krill is currently in beta and may have breaking changes in future releases.

Krill was born out of a Raspberry Pi and can control GPIO pins and serial devices. The Pi install has two differences from a generic Linux server: the Java runtime, and the krill-pi4j hardware service.

Install Java 25 (Azul Zulu — there is no official Java 25 ARM64 build yet)

Krill requires Java 25 or later, but there is currently no official OpenJDK 25 build for ARM64, so on a Raspberry Pi you must install Azul Zulu OpenJDK first:

sudo apt install curl gnupg ca-certificates
curl -s https://repos.azul.com/azul-repo.key | sudo gpg --dearmor -o /usr/share/keyrings/azul.gpg
echo "deb [arch=arm64 signed-by=/usr/share/keyrings/azul.gpg] https://repos.azul.com/zulu/deb stable main" | sudo tee /etc/apt/sources.list.d/zulu.list
sudo apt update
sudo apt install zulu25-jdk-headless

Setup our APT Repository

sudo install -d -m 0755 /etc/apt/keyrings

curl -fsSL https://deb.krill.zone/krill-archive-keyring.gpg \
  | sudo gpg --dearmor -o /etc/apt/keyrings/krill-archive-keyring.gpg

sudo chmod 0644 /etc/apt/keyrings/krill-archive-keyring.gpg

sudo tee /etc/apt/sources.list.d/krill.sources > /dev/null <<EOF
Types: deb
URIs: https://deb.krill.zone
Suites: stable
Components: main
Architectures: $(dpkg --print-architecture)
Signed-By: /etc/apt/keyrings/krill-archive-keyring.gpg
EOF

sudo apt update

Install the krill-pi4j GPIO service and the Server

To control the header pins of a Raspberry Pi you must install the krill-pi4j package alongside krill. It is a wrapper service for the Pi4J library and is required to run Krill with Java 25 or later on a Raspberry Pi. This is an open source library we made that exposes the Pi4J API over gRPC so Krill can use it with the modern JDK 25 FFM API.

sudo apt install krill-pi4j krill

Install both packages together so the GPIO service is present before the server starts.

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Last verified: 2026-05-16