Converts dbt manifest.json to PlantUML ERD diagram. It's not pretty but it's readable.

ConvertTo-PlantUML.ps1

#!/usr/bin/env pwsh

<#
.Synopsis
    Creates a PlantUML ERD diagram from a manifest.json file.
.Parameter Path
    Path to the manifest.json file. Defaults to .\target\manifest.json
#>
[CmdletBinding()]
param (
    [string] $Path = ".\target\manifest.json"
)

$ErrorActionPreference = "Stop"

function Sanitize-ColumnName {
    param (
        [Parameter(Mandatory=$true, ValueFromPipeline=$true)]
        [string] $ColumnName
    )
    process {
        # Strip text in leading parentheses
        $ColumnName -replace '^\s*\([^\)]*\)\s*'
    }
}

"@startuml"
"hide circle"
"skinparam linetype ortho"
# "left to right direction"
$Manifest = Get-Content -Raw -Path $Path | ConvertFrom-Json
$Manifest.nodes.PSObject.Properties | where { $_.MemberType -eq 'NoteProperty' } | foreach {
    $Value = $_.Value
    switch -Regex ($_.Name) {
        'model\..*' {
            "entity `"$($Value.name)`" as $($Value.name) {"
            $Value.columns.PSObject.Properties | foreach {
                "  $($_.Value.name | Sanitize-ColumnName) : $($_.Value.type)"
            }
            "}"
        }
        'test\.[^\.]+\.relationships_.*' {
            $OutTable = $Value.refs[1]
            $OutColumn = $Value.column_name | Sanitize-ColumnName
            $InTable = $Value.refs[0]
            $InColumn = ($Value.name -split '__')[-2]
            "$OutTable::$OutColumn ---> $InTable::$InColumn"
        }
    }
}
"@enduml"

Hi @panasenco - seems we're thinking on the same path. I have an interactive catalog for dbt under development, and one of my upcoming features is in this space - have you put thought into what a good looking solution to this could look like?
ciejer/tangata_local#6