Rollkit

Appearance

On this page

GM world rollup: Part 1 ​

Building a rollup locally ​

🌅 Introduction ​

This tutorial will guide you through building a sovereign gm-world rollup using Rollkit, using Celestia’s data availability and consensus layer to submit Rollkit blocks.

We'll cover setting up Ignite CLI, building a Cosmos-SDK application-specific rollup blockchain, and posting data to Celestia. First, we will test on a local DA network, then to a live testnet, and lastly to mainnet.

  1. Part 1 (This page): Run your rollup and post DA to a local devnet, and make sure everything works as expected.
  2. Part 2: Deploy the rollup, posting to a DA testnet (Mocha). Confirm again that everything is functioning properly.
  3. Part 3: Deploy your rollup to the DA layer's mainnet.

The Cosmos SDK is a framework for building blockchain applications. The Cosmos Ecosystem uses Inter-Blockchain Communication (IBC) to allow blockchains to communicate with one another.

TIP

This tutorial will explore developing with Rollkit, which is still in Alpha stage. If you run into bugs, please write a Github Issue ticket or let us know in our Telegram.

Learn how to restart your rollup.

🤔 What is GM? ​

GM means good morning. It's GM o'clock somewhere, so there's never a bad time to say GM, Gm, or gm. You can think of "GM" as the new version of "hello world".

Dependencies ​

Next, head either to Linux setup or MacOS setup.

Linux setup ​

🏃 Install Golang on Linux ​

Celestia-App, Celestia-Node, and Cosmos-SDK are written in the Golang programming language. You will need Golang to build and run them.

You can install Golang here.

🔥 Install Ignite CLI on Linux ​

First, you will need to create /usr/local/bin if you have not already:

bash
sudo mkdir -p -m 775 /usr/local/bin

Run this command in your terminal to install Ignite CLI:

bash
curl https://get.ignite.com/[email protected]! | bash

TIP

✋ On some machines, you may run into permissions errors like the one below. You can resolve this error by following the guidance here or below.

bash
# Error
jcs @ ~ % curl https://get.ignite.com/[email protected]! | bash


  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
100  3967    0  3967    0     0  16847      0 --:--:-- --:--:-- --:--:-- 17475
Installing ignite v28.3.0..... 
######################################################################## 100.0% 
mv: rename ./ignite to /usr/local/bin/ignite: Permission denied 
============ 
Error: mv failed

The following command will resolve the permissions error:

bash
sudo curl https://get.ignite.com/[email protected]! | bash

A successful installation will return something similar to the response below:

bash
% Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
100  4073    0  4073    0     0   4363      0 --:--:-- --:--:-- --:--:--  4379
Installing ignite v28.3.0..... 
######################################################################## 100.0% 
Password:
Installed at /usr/local/bin/ignite

Verify you’ve installed Ignite CLI by running:

bash
ignite version

The response that you receive should look something like this:

bash
jcs @ ~ % ignite version 
Ignite CLI version: v28.3.0 
Ignite CLI build date: 2024-03-20T15:31:07Z
Ignite CLI source hash: 159abdca88605ed82cb4aabd52618db91069b7af
Ignite CLI config version: v1
Cosmos SDK version: v0.50.5
Your OS:  darwin
Your arch:  arm64
Your Node.js version: v20.4.0
Your go version: go version go1.21.5 darwin/arm64
Your uname -a:  Darwin Joshs-MacBook-Air.local 22.5.0 Darwin Kernel Version 22.5.0: Thu Jun  8 22:21:34 PDT 2023; root:xnu-8796.121.3~7/RELEASE_ARM64_T8112 arm64
Your cwd:  /Users/joshstein
Is on Gitpod:  false

Your development environment is setup! Now, head to part 1.

macOS setup ​

🏃 Install Golang on macOS ​

Celestia-App, Celestia-Node, and Cosmos-SDK are written in the Golang programming language. You will need Golang to build and run them.

You can install Golang here.

🔥 Install Ignite CLI on macOS ​

First, you will need to create /usr/local/bin if you have not already:

bash
sudo mkdir -p -m 775 /usr/local/bin

Run this command in your terminal to install Ignite CLI:

bash
curl https://get.ignite.com/[email protected]! | bash

TIP

✋ On some machines, you may run into permissions errors like the one below. You can resolve this error by following the guidance here or below.

bash
# Error
jcs @ ~ % curl https://get.ignite.com/[email protected]! | bash


  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
100  3967    0  3967    0     0  16847      0 --:--:-- --:--:-- --:--:-- 17475
Installing ignite v28.3.0..... 
######################################################################## 100.0% 
mv: rename ./ignite to /usr/local/bin/ignite: Permission denied 
============ 
Error: mv failed

The following command will resolve the permissions error:

bash
sudo curl https://get.ignite.com/[email protected]! | sudo bash

A successful installation will return something similar the response below:

bash
% Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
100  3967    0  3967    0     0  15586      0 --:--:-- --:--:-- --:--:-- 15931
Installing ignite v28.3.0..... 
######################################################################## 100.0% 
Installed at /usr/local/bin/ignite

Verify you’ve installed Ignite CLI by running:

bash
ignite version

The response that you receive should look something like this:

bash
jcs @ ~ % ignite version 
Ignite CLI version:  v28.3.0
Ignite CLI build date:  2024-03-20T15:31:07Z
Ignite CLI source hash:  159abdca88605ed82cb4aabd52618db91069b7af
Ignite CLI config version: v1
Cosmos SDK version:  v0.50.5
Your OS:   darwin
Your arch:   arm64
Your Node.js version:  v17.9.0
Your go version:  go version go1.21.6 darwin/arm64
Your uname -a:   Darwin Joshs-MacBook-Air.local 22.5.0 Darwin Kernel Version 22.5.0: Thu Jun  8 22:21:34 PDT 2023; root:xnu-8796.121.3~7/RELEASE_ARM64_T8112 arm64
Your cwd:  /Users/joshstein
Is on Gitpod:  false

🍺 Install Homebrew on macOS ​

Homebrew will allow us to install dependencies for our Mac:

bash
/bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"

Be sure to run the commands similar to the output below from the successful installation:

bash
==> Next steps:
- Run these three commands in your terminal to add Homebrew to your PATH:
    echo '# Set PATH, MANPATH, etc., for Homebrew.' >> /Users/joshstein/.zprofile
    echo 'eval "$(/opt/homebrew/bin/brew shellenv)"' >> /Users/joshstein/.zprofile
    eval "$(/opt/homebrew/bin/brew shellenv)"

🏃 Install wget on macOS ​

wget is an Internet file retriever:

bash
brew install wget

Your development environment is setup! Now, head to part 1.

Part 1 ​

This part of the tutorial will teach developers how to easily run a local data availability (DA) devnet on their own machine (or in the cloud). Running a local devnet for DA to test your rollup is the recommended first step before deploying to a testnet. This eliminates the need for testnet tokens and deploying to a testnet until you are ready.

WARNING

Part 1 of the tutorial has only been tested on an AMD machine running Ubuntu 22.10 x64.

Whether you're a developer simply testing things on your laptop or using a virtual machine in the cloud, this process can be done on any machine of your choosing. We tested out the Devnet section (part 1) on a machine with the following specs:

  • Memory: 1 GB RAM
  • CPU: Single Core AMD
  • Disk: 25 GB SSD Storage
  • OS: Ubuntu 22.10 x64

💻 Prerequisites ​

  • Docker installed on your machine

🏠 Running local devnet with a Rollkit rollup ​

First, run the local-celestia-devnet by running the following command:

bash
docker run -t -i \
    -p 26657:26657 -p 26658:26658 -p 26659:26659 -p 9090:9090 \
    ghcr.io/rollkit/local-celestia-devnet:v0.13.1

The docker image runs a celestia bridge node.

🏗️ Building your sovereign rollup ​

Now that you have a Celestia devnet running, we are ready to use Golang to build and run our Cosmos-SDK blockchain.

The Ignite CLI comes with scaffolding commands to make development of blockchains quicker by creating everything that is needed to start a new Cosmos SDK blockchain.

Check your version:

bash
ignite version

Open a new tab or window in your terminal and run this command to scaffold your rollup. Scaffold the chain:

bash
cd $HOME
ignite scaffold chain gm --address-prefix gm

TIP

The --address-prefix gm flag will change the address prefix from cosmos to gm. Read more on the Cosmos docs.

The response will look similar to below:

WARNING

Do not run ignite chain serve as we will build the chain later in the tutorial.

bash
jcs @ ~ % ignite scaffold chain gm --address-prefix gm

⭐️ Successfully created a new blockchain 'gm'. 
👉 Get started with the following commands: 

 % cd gm 
 % ignite chain serve

Documentation: https://docs.ignite.com

This command has created a Cosmos SDK blockchain in the gm directory. The gm directory contains a fully functional blockchain. The following standard Cosmos SDK modules have been imported:

  • staking - for delegated Proof-of-Stake (PoS) consensus mechanism
  • bank - for fungible token transfers between accounts
  • gov - for on-chain governance
  • mint - for minting new units of staking token
  • nft - for creating, transferring, and updating NFTs
  • and more

Change to the gm directory:

bash
cd gm

You can learn more about the gm directory’s file structure here. Most of our work in this tutorial will happen in the x directory.

🗞️ Install Rollkit ​

To swap out CometBFT for Rollkit, run the following command from inside the gm directory:

bash
go mod edit -replace github.com/cosmos/cosmos-sdk=github.com/rollkit/[email protected]
go mod tidy
go mod download

▶️ Start your rollup ​

Download the init-local.sh script to start the chain:

bash
# From inside the `gm` directory
wget https://raw.githubusercontent.com/rollkit/docs/main/scripts/gm/init-local.sh

Run the init-local.sh script:

WARNING

In order to run init-local.sh you need to have the jq command line tool installed. You can install it by running sudo apt-get install jq on Ubuntu or brew install jq on MacOS.

bash
bash init-local.sh

TIP

If you get errors of gmd not found, you may need to add the go/bin directory to your PATH. You can do this by running export PATH=$PATH:$HOME/go/bin and then running the init-local.sh script again.

This will start your rollup, connected to the local Celestia devnet you have running.

Now let's explore a bit.

TIP

If you are restarting your rollup, you'll need to clear the old chain history and binary:

bash
rm -rf $HOME/.gm
rm $HOME/go/bin/gmd

🔑 Keys ​

List your keys:

bash
gmd keys list --keyring-backend test

You should see an output like the following

bash
- address: gm1sa3xvrkvwhktjppxzaayst7s7z4ar06rk37jq7 
  name: gm-key-2 
  pubkey: '{"@type":"/cosmos.crypto.secp256k1.PubKey","key":"AlXXb6Op8DdwCejeYkGWbF4G3pDLDO+rYiVWKPKuvYaz"}'
  type: local
- address: gm13nf52x452c527nycahthqq4y9phcmvat9nejl2 
  name: gm-key 
  pubkey: '{"@type":"/cosmos.crypto.secp256k1.PubKey","key":"AwigPerY+eeC2WAabA6iW1AipAQora5Dwmo1SnMnjavt"}'
  type: local

💸 Transactions ​

Now we can test sending a transaction from one of our keys to the other. We can do that with the following command:

bash
gmd tx bank send [from_key_or_address] [to_address] [amount] [flags]

Set your keys as variables to make it easier to add the address:

bash
export KEY1=gm1sa3xvrkvwhktjppxzaayst7s7z4ar06rk37jq7
export KEY2=gm13nf52x452c527nycahthqq4y9phcmvat9nejl2

So using our information from the keys command, we can construct the transaction command like so to send 42069stake from one address to another:

bash
gmd tx bank send $KEY1 $KEY2 42069stake --keyring-backend test \
--node tcp://127.0.0.1:36657 --chain-id gm --fees 5000stake

TIP

We're using the --node [ip:port] flag to point to port 36657, which is the custom port we used in the init-local.sh script to avoid clashing with 26657 on local-celestia-devnet. We set it here:

bash
--rpc.laddr tcp://127.0.0.1:36657

You'll be prompted to accept the transaction:

bash
auth_info:
  fee:
    amount: []
    gas_limit: "200000"
    granter: ""
    payer: ""
  signer_infos: []
  tip: null
body:
  extension_options: []
  memo: ""
  messages:
  - '@type': /cosmos.bank.v1beta1.MsgSend
    amount:
    - amount: "42069"
      denom: stake
    from_address: gm1sa3xvrkvwhktjppxzaayst7s7z4ar06rk37jq7
    to_address: gm13nf52x452c527nycahthqq4y9phcmvat9nejl2
  non_critical_extension_options: []
  timeout_height: "0"
signatures: []
confirm transaction before signing and broadcasting [y/N]:

Type y if you'd like to confirm and sign the transaction. Then, you'll see the confirmation:

bash
code: 0
codespace: ""
data: ""
events: []
gas_used: "0"
gas_wanted: "0"
height: "0"
info: ""
logs: []
raw_log: '[]'
timestamp: ""
tx: null
txhash: 677CAF6C80B85ACEF6F9EC7906FB3CB021322AAC78B015FA07D5112F2F824BFF

⚖️ Balances ​

Then, query your balance:

bash
gmd query bank balances $KEY2 --node tcp://127.0.0.1:36657

This is the key that received the balance, so it should have increased past the initial STAKING_AMOUNT:

bash
balances: 
- amount: "10000000000000000000042069" 
  denom: stake
pagination:
  next_key: null
  total: "0"

The other key, should have decreased in balance:

bash
gmd query bank balances $KEY1 --node tcp://127.0.0.1:36657

Response:

bash
balances: 
- amount: "9999999999999999999957931" 
  denom: stake
pagination:
  next_key: null
  total: "0"

Next steps ​

Congratulations! You've built a local rollup that posts to a local Celestia devnet. In the next tutorial, you can learn how to post data to Celestia's Arabica devnet.

Released under the APACHE-2.0 License

Copyright © 2023 Rollkit