Simple Digraph class (for use with GraphViz etc.)

Digraph.cs

using System.Collections.Generic;
using System.IO;
using System.Text;
using Colorspace;


public class Digraph
{
	public List<Dependency> Dependencies = new List<Dependency>();

	ColorGenerator _colorgen => new ColorGenerator();

	public void Save(string filename)
	{
		var sb = new StringBuilder();

		sb.AppendLine("digraph g {");
		sb.AppendLine("rankdir = \"LR\"");

		foreach (var d in Dependencies)
		{
			sb.AppendLine($"{d.Source} -> {d.Target} [color=\"{d.Color?? _colorgen.GetRandomHexColor()}\"]".Replace('.', '_'));
		}
		sb.AppendLine("}");

		File.WriteAllText(filename, sb.ToString());
	}
}

public class Dependency
{
	public string Source { get; internal set; }
	public string Target { get; internal set; }
	public string Color { get; internal set; }
}  

internal class ColorGenerator
{
	Random _random => new Random();

	internal string GetRandomHexColor()
	{
		double lightness = 0.4;
		double saturation = 0.75;
		var color = new ColorRGB(new ColorHSL(_random.NextDouble(), saturation, lightness));
		var rgb = new double[] { color.R, color.G, color.B };
		string hexcolor = "#" + String.Join("", rgb.Select(c => Convert.ToByte(c * 255).ToString("X2")));
		Thread.Sleep(20);
		return hexcolor;
	}

}