02 / 15Advanced

Set up your project

You need the following in place before you begin:

Set up PostgreSQL database

Rell needs PostgreSQL 16.3. Without it, the IDE still works but cannot run a node. You can run a console or a remote postchain app with no database at all.

By default, Rell expects these database settings:

database: postchain
user: postchain
password: postchain

Install

Get Homebrew by following the Homebrew setup instructions.

Install PostgreSQL:

shell

brew install postgresql@16brew services start postgresql@16createuser -s postgres

Create and configure the database:

plsql

psql -U postgres -c "CREATE DATABASE postchain WITH TEMPLATE = template0 LC_COLLATE = 'C.UTF-8' LC_CTYPE = 'C.UTF-8' ENCODING 'UTF-8';" -c "CREATE ROLE postchain LOGIN ENCRYPTED PASSWORD 'postchain'; GRANT ALL ON DATABASE postchain TO postchain;"

Install PostgreSQL:
bash
```
sudo apt install postgresql-16
```

Create and configure the database:

bash

sudo -u postgres psql -c "CREATE DATABASE postchain WITH TEMPLATE = template0 LC_COLLATE = 'C.UTF-8' LC_CTYPE = 'C.UTF-8' ENCODING 'UTF-8';" -c "CREATE ROLE postchain LOGIN ENCRYPTED PASSWORD 'postchain'; GRANT ALL ON DATABASE postchain TO postchain;"

Get Docker by following the Docker setup instructions.
Create and configure the database:
dockerfile
```
docker run --name postgres -e POSTGRES_USER=postchain -e POSTGRES_PASSWORD=postchain -p 5432:5432 -d postgres:16.3-alpine3.20
```
note
The Alpine image of PostgreSQL is used here because its default collation settings are the ones you need. You can also set them explicitly with this environment variable:
bash
```
POSTGRES_INITDB_ARGS="--lc-collate=C.UTF-8 --lc-ctype=C.UTF-8 --encoding=UTF-8"
```

Get the PostgreSQL installer from the PostgreSQL download page.
Run the installer, then add the PostgreSQL binaries folder to your environment variables. In the Command Prompt (CMD), run the command below. Check that the path points to your binaries and substitute your installed version for the <version> placeholder:
shell
```
setx POSTGRESQL "C:\Program Files\PostgreSQL\<version>\bin"
```
Close and reopen the Command Prompt (CMD) so the new environment variables take effect. Then run these two commands, one after the other, to create and configure the database:
plsql
```
psql -U postgres -c "CREATE DATABASE postchain WITH TEMPLATE = template0 LC_COLLATE = 'en_US.UTF-8' LC_CTYPE = 'en_US.UTF-8' ENCODING 'UTF-8';"psql -U postgres -c "CREATE ROLE postchain LOGIN ENCRYPTED PASSWORD 'postchain'; GRANT ALL ON DATABASE postchain TO postchain;"
```
note
Some Windows versions produce permission errors or end up with a broken PostgreSQL installation. If you run into this, install Docker and run PostgreSQL in a container instead.

Install Chromia CLI

These steps cover installing and updating the Chromia CLI.

Prerequisite

Confirm the following first:

PostgreSQL database: Follow Set up PostgreSQL database.
RELL_JAVA environment: Chromia CLI runs on a Java runtime, version 21 or later. The package managers handle this for you, so no manual setup is needed. To choose which Java runtime runs Chromia CLI, set the RELL_JAVA environment variable to a valid Java installation.

Installation

Install Chromia CLI through a package manager, or download it directly from the Chromia CLI package registry.

On macOS, install Chromia CLI (chr) as follows:

Install Homebrew if you don't have it yet:

bash

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

bash

brew tap chromia/core https://gitlab.com/chromaway/core-tools/homebrew-chromia.git

Install Chromia CLI:
bash
```
brew install chromia/core/chr
```
info
To pin a particular Chromia CLI version, run:
shell
```
brew install chromia/core/chr@<version>brew unlink chrbrew link chr@<version>
```
Run brew search chr to see which versions are available.
Confirm the installation by printing the version:
bash
```
chr --version
```

On Linux or WSL (Windows Subsystem for Linux), install Chromia CLI (chr) as follows:

Fetch Chromia's apt-repo public key and add it to your trusted keyrings:

bash

curl -fsSL https://apt.chromia.com/chromia.gpg | sudo tee /usr/share/keyrings/chromia.gpg

Add the Chromia repository to your package sources:

bash

echo "deb [arch=amd64 signed-by=/usr/share/keyrings/chromia.gpg] https://apt.chromia.com stable main" | sudo tee /etc/apt/sources.list.d/chromia.list

Refresh your package sources:
bash
```
sudo apt-get update
```
info
If you added apt.chromia.com before Chromia CLI version 0.16.0, run this command so the repository can update:
bash
```
sudo apt-get --allow-releaseinfo-change update
```
After the refresh completes, install Chromia CLI:
bash
```
sudo apt-get install chr
```
Confirm the installation by printing the version:
bash
```
chr --version
```

On Windows, install Chromia CLI (chr) with Scoop as follows:

Install Scoop if you don't have it yet. Run this in PowerShell as Administrator:
powershell
```
iwr -useb get.scoop.sh | iex
```

Add the Chromia bucket to Scoop:

powershell

scoop bucket add chromia https://gitlab.com/chromaway/core-tools/scoop-chromia/

Add the Java bucket to Scoop:
powershell
```
scoop bucket add java
```
With this bucket in place, Scoop can fetch openjdk21, which chromia-cli needs during installation.
Install Chromia CLI:
powershell
```
scoop install chr
```
Confirm the installation by printing the version:
powershell
```
chr --version
```

Updating Chromia CLI

Get the newest Chromia CLI from the package registry. If you installed it through a package manager, update it with:

shell

brew updatebrew upgrade chr

shell

sudo apt-get updatesudo apt-get install chr

shell

scoop updatescoop update chr

Docker

You can also run Chromia CLI inside a standalone Linux container where it comes preinstalled. You still need the PostgreSQL database set up.

The published images require Docker to be installed and configured on your host. The Docker documentation explains how to get Docker for Windows, Mac, and Linux.

Start the Docker container with Chromia CLI pre-installed

To run the latest Chromia CLI, call docker run with the CLI image name followed by chr.

shell

docker run --rm -v $(pwd):/usr/app registry.gitlab.com/chromaway/core-tools/chromia-cli/chr:<latest version> chr

Windows Command Prompt Users

The $(pwd) syntax does not work in Windows Command Prompt (cmd). Use one of these instead:

PowerShell: $(Get-Location) or $(pwd)
Command Prompt: %CD%

Command Prompt example:

cmd

docker run --rm -v %CD%:/usr/app registry.gitlab.com/chromaway/core-tools/chromia-cli/chr:<latest version> chr

For updating or removing the Docker image, consult the Docker CLI reference.

bash

#!/bin/bash# Allocate a pseudo-TTY one when run in interactive modeif [ -t 0 ] && [ -t 1 ] ; then TTY="--tty"; else TTY=""; fidocker run \  # Sets the network to host to not need to change the database hostname (linux only)  --network=host \  # Set timezone based on system settings (linux only)  -e TZ=$(cat /etc/timezone) \  # Sets process ownership to current user  --user $(id -u):$(id -g) \  --mount type=bind,source="/etc/passwd",target=/etc/passwd,readonly \  --mount type=bind,source="/etc/group",target=/etc/group,readonly \  # Configures ssh-agent (only needed if chr install is called on non-public repositores)  -e SSH_AUTH_SOCK=$SSH_AUTH_SOCK \  --volume "$SSH_AUTH_SOCK:$SSH_AUTH_SOCK" \  --mount type=bind,source="${HOME}/.ssh",target=${HOME}/.ssh,readonly \  --mount type=bind,source="${HOME}/.config/jgit",target=${HOME}/.config/jgit \  # Mounts current folder into the container (Use `Get-Location` on PowerShell)  --mount type=bind,source="$(pwd)",target=/usr/app \  --interactive ${TTY} \  --rm \  registry.gitlab.com/chromaway/core-tools/chromia-cli/chr:${CHR_VERSION:-latest} chr "$@"

Windows Command Prompt Users

This bash script relies on $(pwd), which Windows Command Prompt does not support. On Windows:

PowerShell: run the command unchanged; PowerShell also understands $(pwd)
Command Prompt: Swap $(pwd) for %CD% in the mount command

Mount line adjusted for Command Prompt:

cmd

--mount type=bind,source="%CD%",target=/usr/app \

First, create a new project with Chromia CLI:

shell

chr create-rell-dapp rell_marketplace --template=plain-multi

shell

cd rell_marketplace

Next, add the FT4 library. In chromia.yml, create a libs section, add ft4 to it, and set your public key as the dapp's admin key:

chromia.yml

blockchains:  rell_marketplace:    module: maincompile:  rellVersion: 0.14.9database:  schema: schema_rell_marketplacetest:  modules:    - rell_marketplace_testlibs:  ft4:    registry: https://gitlab.com/chromaway/ft4-lib.git    path: rell/src/lib/ft4    tagOrBranch: v1.2.0r    rid: x"E96915FD7C9A5DD4E183D86F4A5B4BB5083A7CC1EDEB1465EDFFC926E67C93F6"    insecure: false  iccf:    registry: https://gitlab.com/chromaway/core/directory-chain    path: src/lib/iccf    tagOrBranch: 1.87.0    rid: x"9C359787B75927733034EA1CEE74EEC8829D2907E4FC94790B5E9ABE4396575D"    insecure: false

Remove the src/rell_marketplace_test directory.

Install FT4 with:

shell

chr install

Your project is now ready for FT4. The following lessons build on this setup to create assets, transfer tokens, and register user accounts.

Written for this site from Chromia’s public course. Code samples are the course’s own.