What is maui-platform-backend?

Guidance for building a .NET MAUI backend for a new platform, or adding platform-specific controls and services. A backend here is the code that connects shared MAUI UI to a platform's native APIs.

Use it to add targets such as GTK, AppKit, Avalonia, or terminal interfaces, implement control handlers, add Essentials services, or check platform coverage.

It helps map MAUI controls, layouts, gestures, text, images, fonts, and threading to an unfamiliar platform while keeping project and packaging work consistent.

How dotnet/maui-labs configures Claude Code and Codex

Reuse

Borrowing it

Nothing to install: this file belongs to dotnet/maui-labs. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file

curl -O https://raw.githubusercontent.com/dotnet/maui-labs/main/.github/skills/maui-platform-backend/SKILL.md

Clone the repo

git clone --depth 1 https://github.com/dotnet/maui-labs

Made for: Claude Code, Codex.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

README.md

[![agentmods](https://agentmods.dev/badge/skills/dotnet/maui-labs/maui-platform-backend/github.svg)](https://agentmods.dev/skills/dotnet/maui-labs/maui-platform-backend)

Your own site

<a href="https://agentmods.dev/skills/dotnet/maui-labs/maui-platform-backend"><img src="https://agentmods.dev/badge/skills/dotnet/maui-labs/maui-platform-backend/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

Your own site · 80×15

<a href="https://agentmods.dev/skills/dotnet/maui-labs/maui-platform-backend"><img src="https://agentmods.dev/badge/skills/dotnet/maui-labs/maui-platform-backend.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 133 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.

When invoked 2,729 The whole file, excluding the scripts and references it only reads on demand.

Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe. Third-party audits

NVIDIA SkillSpector pass 7 Sept 2026

How audits are shown

Origin original No closer match found in the catalogue.

Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

Model	Per session	Once invoked
Fable 5.1	$0.00133	$0.02729
Opus 5.5	$0.00053	$0.01092
Sonnet 5.5	$0.00027	$0.00546
Haiku 4.5	$0.00013	$0.00273

Measured 2mo ago against content hash d35b0cd290dd, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

maui-platform-backend scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 2mo ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

.github/skills/maui-platform-backend/SKILL.md · 141 lines

How it starts

The opening of the file, as written. The whole thing — 141 lines — stays where its author put it; the contents beside it link to each section on GitHub.

.NET MAUI Platform Backend Implementation

Guide for creating a complete .NET MAUI backend for a new target platform inside the dotnet/maui-labs repository.

When to Use This Skill

Use this skill when:

Creating a new .NET MAUI backend for a platform (e.g., Avalonia, WinUI3, Terminal/TUI)
Implementing or fixing a specific control handler for an existing backend
Adding MAUI Essentials service implementations for a platform
Setting up build targets, NuGet packaging, or dotnet new templates for a backend
Scaffolding the project structure for a new platform under platforms/
Debugging handler rendering issues using MAUI DevFlow
Auditing handler coverage or implementation parity

Process

Phase 0: Research & Architecture Planning

Before writing any code, research the target platform:

Identify the native view base class (equivalent of UIView/NSView/Gtk.Widget)
Understand the layout system — MAUI computes frames; how does the platform apply them?
Understand main-thread dispatching — what mechanism does the platform use?
Map MAUI concepts to platform APIs: gesture system, text rendering, image loading, font system, web engine
Review known extensibility gaps — see references/extensibility-gaps.md for workarounds

Reference the canonical implementation: Study the Linux.Gtk4 backend at platforms/Linux.Gtk4/ on main. It includes three subprojects: core handlers (Linux.Gtk4), essentials (Linux.Gtk4.Essentials), and Blazor WebView (Linux.Gtk4.BlazorWebView). Also reference the MAUI source at dotnet/maui.

Phase 1: Scaffold Project Structure

Create the self-contained backend under platforms/[Platform.Name]/ following the pattern in references/project-structure.md.

Key files to create first:

Directory.Build.props, Directory.Packages.props, [Platform.Name].slnx
src/[Platform.Name]/[Platform.Name].csproj with core handlers
samples/[Platform.Name].Sample/ with a minimal test app

Read the full file on GitHub · 141 lines

Files

What ships with it

5 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

2mo ago First seen · 141 lines · 133 tokens per session scan A d35b0cd290dd

Subscribe to this mod's changes

maui-platform-backend is a skill published in the GitHub repository dotnet/maui-labs (235 stars, last pushed yesterday), licensed MIT. It adds 133 tokens to every session and 2,729 once invoked, about $0.0005 per session on Opus 5.5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

Backend and APIs C# and .NET Languages ai android desktop dotnet ios maccatalyst

maui-platform-backend next to 6 skills from other repositories
Mod	Type	Stars	Last push	Licence	Scan	Tokens	Works with
maui-platform-backenddotnet/maui-labs	Skill	235	yesterday	MIT	A	133	Claude Code, Codex
worker-servicesmanagedcode/dotnet-skills	Skill	508	yesterday	MIT	A	109	Claude Code, Codex
aspnet-coremanagedcode/dotnet-skills	Skill	508	yesterday	MIT	A	122	Claude Code, Codex
minimal-apismanagedcode/dotnet-skills	Skill	508	yesterday	MIT	A	105	Claude Code, Codex
web-apimanagedcode/dotnet-skills	Skill	508	yesterday	MIT	A	115	Claude Code, Codex
managedcode-communicationmanagedcode/dotnet-skills	Skill	508	yesterday	MIT	A	114	Claude Code, Codex
grpcmanagedcode/dotnet-skills	Skill	508	yesterday	MIT	A	95	Claude Code, Codex

maui-labs: Skill for Claude Code