Configuration

The gateway acts as a bridge between the execution layer and the Threshold Key Management System (TKMS). Due to its central role, it needs to be properly configured. This document details all the environment variables and gives an example of docker compose to run the gateway.

Dependencies

• Zama Gateway: Depends on fhEVM and Gateway KV Store, which is initialized with the Zama KMS Docker Compose command. Therefore, this is the last Docker Compose command that should be run.

Prerequisites

• Docker 26+ installed on your system.

• fhEVM validator running and configured.

• TKMS running and configured.

Configuring Docker Compose Environment Variables

Example Docker Compose for Zama Gateway

name: zama-gateway

services:

  gateway:
    image: ghcr.io/zama-ai/kms-blockchain-gateway-dev:latest
    command:
      - "gateway"
    environment:
      - GATEWAY__ETHEREUM__CHAIN_ID=9000
      - GATEWAY__ETHEREUM__LISTENER_TYPE=FHEVM_V1_1
      - GATEWAY__ETHEREUM__WSS_URL=ws://fhevm-validator:8546
      - GATEWAY__ETHEREUM__HTTP_URL=http://fhevm-validator:8545
      - GATEWAY__ETHEREUM__FHE_LIB_ADDRESS=000000000000000000000000000000000000005d
      - GATEWAY__ETHEREUM__ORACLE_PREDEPLOY_ADDRESS=c8c9303Cd7F337fab769686B593B87DC3403E0ce
      - GATEWAY__KMS__ADDRESS=http://kms-validator:9090
      - GATEWAY__KMS__KEY_ID=408d8cbaa51dece7f782fe04ba0b1c1d017b1088
      - GATEWAY__STORAGE__URL=http://gateway-store:8088
      - ASC_CONN__BLOCKCHAIN__ADDRESSES=http://kms-validator:9090
      - GATEWAY__ETHEREUM__RELAYER_KEY=7ec931411ad75a7c201469a385d6f18a325d4923f9f213bd882bbea87e160b67

Zama Gateway requires several specific configurations as shown in the provided docker-compose-gateway.yml file.

Variable	Description	Default Value
GATEWAY__ETHEREUM__CHAIN_ID	Chain ID for fhEVM	9000
GATEWAY__ETHEREUM__LISTENER_TYPE	Listener type for Ethereum gateway	FHEVM_V1_1
GATEWAY__ETHEREUM__WSS_URL	WebSocket URL for fhEVM Ethereum. You need to run fhEVM first and set this data	ws://localhost:9090
GATEWAY__ETHEREUM__FHE_LIB_ADDRESS	FHE library address for Ethereum gateway. This should be obtained from fhEVM once it is running and configured	000000000000000000000000000000000000005d
GATEWAY__ETHEREUM__ORACLE_PREDEPLOY_ADDRESS	Oracle predeploy contract address for fhEVM gateway	c8c9303Cd7F337fab769686B593B87DC3403E0cd
GATEWAY__KMS__ADDRESS	Address for KMS gateway	http://localhost:9090
GATEWAY__KMS__KEY_ID	Key ID for KMS gateway. Refer to the How to Obtain KMS Key ID section	04a1aa8ba5e95fb4dc42e06add00b0c2ce3ea424
GATEWAY__STORAGE__URL	URL for storage gateway	http://localhost:8088
ASC_CONN__BLOCKCHAIN__ADDRESSES	Blockchain addresses for ASC connection. Same as GATEWAY__KMS__ADDRESS	http://localhost:9090
GATEWAY__ETHEREUM__RELAYER_KEY	Private key of the relayer	7ec931411ad75a7c201469a385d6f18a325d4923f9f213bd882bbea87e160b67

Steps for Running

1. Run the Zama Gateway Docker Compose:

docker compose -f docker-compose-gateway.yml up -d

⚠️ Requirement: At start, the Gateway will try to connect to the websocker URL GATEWAY__ETHEREUM__WSS_URL. Ensure it is running and the port is opened.

KMS Key ID

To obtain the Key ID for the GATEWAY__KMS__KEY_ID environment variable, run the following command:

> docker run -ti ghcr.io/zama-ai/kms-service-dev:latest ls keys/PUB/PublicKey
04a1aa8ba5e95fb4dc42e06add00b0c2ce3ea424  8e917efb2fe00ebbe8f73b2ba2ed80e7e28970de