Complete Build and Publish Script. Will deploy all projects to publishing target, no HPP required.

Build.ps1

param(
  [Parameter()]
  [switch]$NoBuild, 
  [Parameter()]
  [switch]$NoSync,
  [Parameter()]
  [string]$CmHost="https://habitatstarterkit.local",
  [Parameter()]
  [string]$SolutionName="HabitatStarterKit.sln",
  [Parameter()]
  [ValidateSet("Debug", "Release")]
  [string]$BuildConfiguration="Debug"
)

$ErrorActionPreference = "Stop"

if(!$NoBuild)
{
    $vssetup = Get-Module -ListAvailable -Name VSSetup
    if(-Not $vssetup)
    {
        Write-Host "`nInstalling Visual Studio Locator..`n" -ForegroundColor DarkGray
        Install-Module VSSetup
    }

    $vsversion = Get-VSSetupInstance -All | Select-VSSetupInstance -Latest
    if(-Not $vsversion)
    {
        Write-Host "Could not locate MSBuild. Did you follow all the prerequisite installation steps?" -ForegroundColor Red
        Exit
    }

    $msbuild = $vsversion.InstallationPath + "\MSBuild\Current\Bin\MSBuild.exe"

    Write-Host "`nBuilding with MSBuild..`n" -ForegroundColor DarkGray
    & $msbuild $SolutionName    -t:restore,build -p:RestorePackagesConfig=true `
                                /p:Configuration=$BuildConfiguration /p:DeployOnBuild=true /p:DeployDefaultTarget=WebPublish `
                                /p:WebPublishMethod=FileSystem /p:DeleteExistingFiles=false `
                                /p:publishUrl=$PSScriptRoot\data\cm\website
}

if(!$NoSync)
{
    Import-Module $PSScriptRoot\tools\config.psm1
    $SharedSecret = Get-EnvVar "UNICORN_SHARED_SECRET"
    if (-Not $SharedSecret)
    {
        Write-Host "UNICORN_SHARED_SECRET not defined in .env file" -ForegroundColor Red
        Exit
    }

    Write-Host "`nWarming up Sitecore..." -ForegroundColor DarkGray
    Invoke-WebRequest $CmHost -UseBasicParsing | out-null
    Write-Host "Warmed up!`n"

    Write-Host "`nSyncing with Unicorn..." -ForegroundColor DarkGray
    Import-Module $PSScriptRoot\packages\Unicorn.4.1.4\tools\PSAPI\Unicorn.psm1
    $controlPanelUrl = $CmHost + "/unicorn.aspx"
    Sync-Unicorn -ControlPanelUrl $controlPanelUrl -SharedSecret $SharedSecret
}

Config.psm1

function Get-EnvVar {
  param(
    [Parameter(Mandatory = $true)]
    [ValidateNotNullOrEmpty()]
    [string] 
    $Key
  )

  select-string -Path ".env" -Pattern "^$Key=(.+)$" | % { $_.Matches.Groups[1].Value }
}


function Read-UserEnvFile {
  param(
    [Parameter()]
    [string] $EnvFile = ".env.user"
  )

  if (Test-Path $EnvFile) {
      Write-Host "User specific .env file found. Starting Docker with custom user settings." -ForegroundColor Green
      Write-Host "Variable overrides:-" -ForegroundColor Yellow
      
      Get-Content $EnvFile | Where-Object { $_ -notmatch '^#.*' -and $_ -notmatch '^\s*$' } | ForEach-Object {
          $var, $val = $_.trim().Split('=')
          Write-Host "  $var=$val" -ForegroundColor Yellow
          Set-Item -Path "env:$($var)" -Value $val
      }
  }
}


Export-ModuleMember -Function *

docker-compose.override.yml

(just snippets)

    environment: 
      UNICORN_SHARED_SECRET: ${UNICORN_SHARED_SECRET}
    volumes:
      - .\unicorn:C:\inetpub\wwwroot\App_Data\unicorn

FindMsBuild.ps1

$vssetup = Get-Module -ListAvailable -Name VSSetup

if(-Not $vssetup)
{
    Write-Host "`nInstalling Visual Studio Locator..`n" -ForegroundColor DarkGray
    Install-Module VSSetup
}

$vsversion = Get-VSSetupInstance -All | Select-VSSetupInstance -Latest
if(-Not $vsversion)
{
    Write-Host "Could not locate MSBuild. Did you follow all the prerequisite installation steps?" -ForegroundColor Red
    Exit
}

$msbuild = $vsversion.InstallationPath + "\MSBuild\Current\Bin\MSBuild.exe"

z.Unicorn.SharedSecret.config

<configuration xmlns:patch="http://www.sitecore.net/xmlconfig/">
	<sitecore>
		<unicorn>
			<authenticationProvider>
				<SharedSecret>$(env:UNICORN_SHARED_SECRET)</SharedSecret>
				<!-- 
					Writes the reason why failed automated tool authentications failed to the Sitecore logs.
					Will result in writing your shared secret to the logs as part of the signature base,
					so disable it unless you're debugging failed authentications.
				-->
				<WriteAuthFailuresToLog>false</WriteAuthFailuresToLog>
			</authenticationProvider>
		</unicorn>
	</sitecore>
</configuration>

Get-VSSetupInstance -All

InstanceId          : 8631dbc0
DisplayName         : Visual Studio Professional 2019
InstallationVersion : 16.9.31205.134
InstallationPath    : C:\Program Files (x86)\Microsoft Visual Studio\2019\Professional
InstallDate         : 25/03/2021 14:16:54

InstanceId          : 8826a071
DisplayName         : Visual Studio Build Tools 2019
InstallationVersion : 16.9.31205.134
InstallationPath    : C:\Program Files (x86)\Microsoft Visual Studio\2019\BuildTools
InstallDate         : 25/03/2021 14:11:03

VSSetup source: https://github.com/microsoft/vssetup.powershell

Config.psm1 sourced from here https://github.com/konabos/konabos-docker-examples/blob/master/sitecore-xp0-sxa-jss/docker/tools/util.psm1

Nuget package restore and build reference: https://docs.microsoft.com/en-us/nuget/reference/msbuild-targets#restoring-and-building-with-one-msbuild-command