How to Join the Nebulas Testnet


We are glad to release the Nebulas Testnet. It simulates the Nebulas network and NVM, and allows developers to interact with Nebulas without paying the cost of gas.


The Nebulas Testnet‘s executable file and dependant libraries need to be built first. Several important modules are highlighted below:

  • NEB: The main process of the Nebulas Testnet. NEB and NBRE run in standalone processes, and communicate through IPC.

Details of building the modules can be found in tutorials.


The testnet configuration files are in the folder testnet/conf under testnet branch, including:


All configurable information about the genesis block is defined in genesis.conf, such as:

  • meta.chain_id: chain identity.
  • consensus.dpos.dynasty: the initial dynasty of validators.
  • token_distribution: the initial allocation of tokens.
Attention: DO NOT change the genesis.conf.


All configurable information about the runtime is defined in config.conf.

Please check the template.conf to find more details about the runtime configuration.

Tips: the official seed node info is as below,

Miner config

Nodes can participate in mining and share rewards after signing up for mining. The miner node needs to turn on the mine switch and configure both the miner address and reward address(coinbase).

miner config example:

chain {
  # testnet chainID
  chain_id: 1001
  # testnet datadir, should be different with private chain
  datadir: "testnet/data.db"
  keydir: "keydir"
  # testnet genesis.conf
  genesis: "testnet/conf/genesis.conf"
  # testnet dynasty.conf
  dynasty: "testnet/conf/dynasty.conf"
  # start mine
  start_mine: true
  # receive the mining award, must change to your address
  coinbase: "n1XkoVVjswb5Gek3rRufqjKNpwrDdsnQ7Hq"
  # block signature address, needs to be placed in the node's configuration `keydir`. Also make sure that the address is the node address at the time of registration
  miner: "n1FF1nz6tarkDVwWQkMnnwFPuPKUaQTdptE"
  passphrase: "passphrase"

  signature_ciphers: ["ECC_SECP256K1"]


Since Nebulas testnet is running there for certain period of time, it will take quite some time to sync all the testnet data from scratch.

For developers‘ convenience, we provided a offline data package, which already includes the data of more than 1.2 million blocks, you can download the package directly by following either link below (choose whichever is faster for you):

Please note that, the data package should be put under the same path of “datadir“ as specified in your config.conf file.

API List

Test Endpoint:

API URL Protocol

More Nebulas APIs at RPC.


Feel free to join Nebulas Testnet. If you did find something wrong, please submit an issue or submit a pull request to let us know, we will add your name and url to this page as soon as possible.