Oct 2020 – Nov 2020

Cloud-Callable Automation Harness for a Native Windows Desktop App

Molecular Matrix · Full Stack Developer

Desktop→API

Native App as a Service

JSON

Structured Results

Unattended

Deterministic Sessions

UI Automation

Accessibility-ID Control

Growth & Stability

~60%

API Response Time Reduced

30+

Manual Workflows Eliminated

1000s

Real-time Synced Users

Overview

At Molecular Matrix, I wrapped a native Windows desktop analysis application (CPIDR) behind an HTTP API so a cloud system could drive it programmatically and get structured results back. The pattern: fill-fields-then-capture-output, exposed as a deterministic backend endpoint instead of a manual desktop task.

The Problem

A required analysis tool existed only as a native Windows desktop app

No programmatic or API way to run it from the cloud or at scale

Operation was manual — a person entered inputs and read results by hand

Results needed to return as structured data for downstream systems

Unattended runs required deterministic, reliable session handling

The Solution

An ASP.NET Core API that launches and drives the desktop app via WinAppDriver

UI Automation to locate controls by accessibility ID and enter values

Programmatic trigger of the analyze action and read-back of the result

A structured JSON API response returned to callers

Deterministic session teardown for repeatable, unattended runs

Architecture

Core Components

HTTP API wrapper (ASP.NET Core)WinAppDriver session managementUI Automation element location and field entryResult capture and JSON serializationConfigurable executable paths and timeout handling

Technical Design

ASP.NET Core (.NET) API service

Appium.WebDriver with WindowsDriver attaching to the target app

Microsoft UI Automation (accessibility-tree element location)

Injected PathConfig for configurable executable paths

Implicit-wait timeouts and finally-block teardown (Close, Quit, WaitForExit)

React front end for interaction and testing

My Role: Full Stack Developer (Backend-heavy)

Built the ASP.NET Core API wrapping the desktop application

Implemented WinAppDriver / Appium session attach and control

Located controls via UI Automation by accessibility ID

Captured output and returned it as structured JSON

Implemented deterministic session teardown and timeout handling

Made executable paths configurable via injected config

Key Achievements

🔥

Exposed deterministic native-desktop automation as a cloud-callable API

🔥

Turned a manual desktop tool into a programmatic, repeatable service

🔥

Returned structured JSON results for downstream processing

🔥

Built reliable unattended session-lifecycle management

Impact

📊

Enabled cloud systems to run a desktop-only tool programmatically

📊

Removed manual data entry and result reading

📊

Made the analysis repeatable, scriptable, and integratable

📊

Produced a reusable pattern for wrapping desktop apps as backend services

Tech Stack

Backend

C#, .NET, ASP.NET Core

Automation

WinAppDriver, Appium.WebDriver, Microsoft UI Automation

Frontend

React.js

Pattern

Desktop UI automation as an HTTP API

What I Help With

Scalable Backend Systems

High-performance APIs and microservices

Complex Integrations

Stripe, Shopify, Microsoft Graph, telecom

AI & Automation

LLM workflows, document processing

Identity & Security

OAuth, Entra ID, Cognito

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