A few lines of PowerShell can turn a seed into a shareable little universe: glowing moon, scattered stars, and a new constellation every time you change the seed.

run.ps1

#requires -Version 7.0
# Pick a fixed seed so the cloud validation output stays reproducible.
$seed = 2718
$outputPath = Join-Path $PSScriptRoot 'night-sky.svg'

# Create a shareable SVG file using the generated PowerShell script.
& (Join-Path $PSScriptRoot 'solution.ps1') -Seed $seed -OutputPath $outputPath | Format-List

solution.ps1

#requires -Version 7.0
[CmdletBinding()]
param(
  # Set the seed so the same input creates the same sky every time.
  [int] $Seed = 2718,
  # Choose where to write the new SVG artwork.
  [Parameter(Mandatory)]
  [string] $OutputPath
)

# Use a local random generator so this script does not change global random state.
$random = [System.Random]::new($Seed)
$width = 720
$height = 420
$stars = [System.Collections.Generic.List[string]]::new()

# Generate a bounded set of tiny stars with deterministic positions and sizes.
for ($index = 0; $index -lt 72; $index++) {
  $x = $random.Next(18, $width - 18)
  $y = $random.Next(16, $height - 16)
  $radius = [math]::Round($random.NextDouble() * 1.5 + 0.4, 2)
  $opacity = [math]::Round($random.NextDouble() * 0.55 + 0.35, 2)
  $stars.Add(('<circle cx="{0}" cy="{1}" r="{2}" fill="#f4f7ff" opacity="{3}"/>' -f $x, $y, $radius, $opacity))
}

# Create a small constellation from fixed points so the shape is easy to spot.
$constellation = @(
  '<polyline points="120,275 190,230 245,270 305,205 360,230 425,160"'
  'fill="none" stroke="#9fe7ff" stroke-width="2" opacity="0.85"/>'
  '<circle cx="120" cy="275" r="4" fill="#a8e9ff"/>'
  '<circle cx="190" cy="230" r="4" fill="#a8e9ff"/>'
  '<circle cx="245" cy="270" r="4" fill="#a8e9ff"/>'
  '<circle cx="305" cy="205" r="4" fill="#a8e9ff"/>'
  '<circle cx="360" cy="230" r="4" fill="#a8e9ff"/>'
  '<circle cx="425" cy="160" r="4" fill="#a8e9ff"/>'
) -join [Environment]::NewLine

# Build the SVG as plain text with a night gradient, moon, stars, and constellation.
$svg = @"
<svg xmlns="http://www.w3.org/2000/svg" width="$width" height="$height" viewBox="0 0 $width $height">
  <defs>
    <linearGradient id="sky" x1="0" y1="0" x2="1" y2="1">
      <stop offset="0%" stop-color="#101a44"/>
      <stop offset="55%" stop-color="#263d73"/>
      <stop offset="100%" stop-color="#572f65"/>
    </linearGradient>
    <radialGradient id="moonGlow">
      <stop offset="0%" stop-color="#fff8cf" stop-opacity="0.75"/>
      <stop offset="100%" stop-color="#fff8cf" stop-opacity="0"/>
    </radialGradient>
  </defs>
  <rect width="100%" height="100%" fill="url(#sky)"/>
  <circle cx="575" cy="105" r="90" fill="url(#moonGlow)"/>
  <circle cx="575" cy="105" r="34" fill="#fff3b0"/>
  $($stars -join [Environment]::NewLine)
  $constellation
  <text x="30" y="390" fill="#dce8ff" font-family="sans-serif" font-size="16">A tiny sky, generated with PowerShell 7 ┬╖ seed $Seed</text>
</svg>
"@

# Create the selected output directory when it does not yet exist.
$parent = Split-Path -Parent $OutputPath
if (-not (Test-Path -LiteralPath $parent -PathType Container)) {
  New-Item -ItemType Directory -Path $parent -Force | Out-Null
}

# Save the vector image as UTF-8 without a byte-order mark.
[System.IO.File]::WriteAllText($OutputPath, $svg, [System.Text.UTF8Encoding]::new($false))

# Return a short summary while leaving the image ready to open in a browser.
[pscustomobject]@{
  File       = [System.IO.Path]::GetFileName($OutputPath)
  Seed       = $Seed
  StarCount  = $stars.Count
  Dimensions = ('{0}x{1}' -f $width, $height)
}

https://dougfinke.dev/idea-lab/#lab-2026-09-29-0300-one-engine-two-front-doors