Keying Wu, Developer in Frankfurt, Hessen, Germany
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Keying Wu

Verified Expert  in Engineering

Full-stack Developer

Frankfurt, Hessen, Germany
Toptal Member Since
October 27, 2022

Keying is a seasoned developer and leader with six years of experience. With hands-on experience in all stages of software development and managerial duties, she is a lifelong learner, a completionist, and a problem solver. Keying's expertise includes back-end services with Java, C#.NET, Python, REST, databases with Oracle, PostgreSQL, and Redis SQL, front end with Angular, and cloud technologies such as AWS.


Helaba Invest
Angular, C#, Azure Functions, Microsoft Dynamics 365, Python, FastAPI...
Yara International - Expert Functions (IT)
Angular, C#.NET, Mapbox, NestJS, PostgreSQL, Node.js, React, Microservices...
C#.NET, Angular, TypeScript, Oracle SQL, PL/SQL, Jenkins, IIS, C++, Python...




Preferred Environment

Visual Studio, Visual Studio Code (VS Code), C#.NET, Python, TypeScript, Full-stack, Java, IntelliJ IDEA

The most amazing...

...thing I've developed is an issuance platform for derivative products, issuing 200 million products and executing 1+ million workflow actions on a daily basis.

Work Experience

Freelance Full-stack Developer

2023 - 2024
Helaba Invest
  • Leveraged Power Automate to streamline sales processes in CRM, enabling automatic data entry and updates. Reduced manual workload for sales teams, leading to increased efficiency.
  • Developed a revolutionary solution leveraging Azure OpenAI Service, incorporating a chatbot with bulk processing capabilities. This solution automates the extraction of key information from the bank's extensive legal documents.
  • Tailored Microsoft Dynamics 365, integrating it with Azure Functions plugins. This customization was pivotal in aligning the CRM's capabilities precisely to an esteemed investment institute's unique and intricate requirements.
  • Redesigned the CRM's sales opportunity module, ensuring sales teams had precise, efficient tools. The account entity was enhanced to support KYT and KYC compliance, guaranteeing rigorous client verification and transaction oversight.
  • Developed and maintained multiple Jenkins pipelines, optimizing the continuous integration and continuous deployment (CI/CD) process for Microsoft Dynamics 365 and Windows Presentation Foundation (WPF) solutions.
  • Built a comprehensive Asset Manager Service (AMS) portal using Angular, Python, Docker, and an Oracle database. It was a pivotal data catalog, significantly enhancing data retrieval efficiency and accuracy.
Technologies: Angular, C#, Azure Functions, Microsoft Dynamics 365, Python, FastAPI, Oracle Database, Microsoft SQL Server, PyCharm, Docker, ASP.NET, Microsoft Dynamics, Microsoft Dynamics CRM, Dynamics CRM 365, Microsoft Power Apps, Microsoft Power BI, Jenkins, Microsoft Power Automate, Azure, Presentation Foundation, ChatGPT, Azure OpenAI Service, Azure AI Search, OpenAI, Retrieval-augmented Generation (RAG)

Freelance Full-stack Developer

2023 - 2023
Yara International - Expert Functions (IT)
  • Led the design and implementation of the Soil Health Score feature using Angular, providing users with a responsive and interactive interface to assess and improve soil quality. Worked on advanced feature development with Angular.
  • Implemented an intuitive trend chart functionality using Chart.js integrated with Angular, enabling users to visualize historical soil data and identify patterns over time seamlessly. Worked on data visualization with Chart.js and Angular.
  • Leveraged C# to develop robust back-end services, facilitating the efficient processing and retrieval of soil data and ensuring seamless interactions with the front end. Worked on the back-end development in C#.
Technologies: Angular, C#.NET, Mapbox, NestJS, PostgreSQL, Node.js, React, Microservices, Kubernetes, Microservices Architecture, NPM, Databases, WordPress

Lead Software Engineer

2021 - 2022
  • Led the project team to develop an investment platform,, for structured products using Angular, C#.NET, and Java.
  • Automated release tests upon implementing new features by integrating a Jenkins CI/CD pipeline, resulting in a 50% reduction during the execution time of the regression test.
  • Migrated the old UI and rewrote the UI part of the issuance platform using Angular, PrimeNG, and WPF. Reimplemented a front-end framework and maintained a reusable component set.
Technologies: C#.NET, Angular, TypeScript, Oracle SQL, PL/SQL, Jenkins, IIS, C++, Python, WCF Web Services, Windows Presentation Foundation (WPF), CSS, Web Development, Software Design, JavaScript, Back-end, HTML, SQL, Git, Full-stack, REST APIs, Automation, Test Automation, Troubleshooting, Root Cause Analysis, .NET, CI/CD Pipelines, XAML, PostgreSQL, Architecture, API Development, API Integration, .NET 4, ASP.NET Core MVC, Databases, Docker, .NET Core, Java, Apache Tomcat, Java EE, C#, SQLAlchemy, NPM, Oracle, ASP.NET

Senior Software Engineer

2019 - 2021
  • Developed an issuance platform for structured products using Java and C# .NET, Oracle database, and Angular, which issued 200 million derivative products, executing one million workflow actions daily.
  • Built a platform for issuing customized structured derivative products for private investors using Angular/C#.
  • Optimized the workflow engine with C#, which executes more than 100 million actions daily.
  • Automated the evaluation process of release test results with Excel VBA.
Technologies: C#.NET, Angular, TypeScript, Windows PowerShell, Model View ViewModel (MVVM), Web MVC, Oracle SQL, Windows Server, IIS, Back-end, APIs, REST APIs, WCF Web Services, Redmine, PL/SQL, PrimeNG, C#, Jenkins, Back-end Development, Full-stack, Test Automation, Automation, Troubleshooting, Root Cause Analysis, .NET, CI/CD Pipelines, XAML, API Development, API Integration, .NET 4, Databases, Docker, Java, Java EE, SQLAlchemy, NPM, Oracle, ASP.NET

Quantitative Business Analyst

2019 - 2019
Devnet GmbH
  • Developed complex advancement reports using PL/SQL for trading and sales of investment banking departments at UniCredit.
  • Optimized a release test/regression test based on new features of trading and sales applications.
  • Wrote SQL scripts, queries, and stored procedures to extract data.
  • Optimized database performance by tuning queries and indexes.
Technologies: C#.NET, C#, Altova XML, Oracle SQL, PL/SQL, Redmine, Windows PowerShell, Windows Server, Visual Studio, Jenkins, Data Visualization, Data Engineering, Automation, Test Automation, Batch, Commerce, NPM

Software Engineer

2016 - 2019
BMW Group via EVA Fahrzeugtechnik GmbH
  • Developed dynamic simulation and lifetime estimation tools for high-voltage batteries using MATLAB and Python, leveraging physics-based models for optimal profile estimation and building a comprehensive lithium-ion battery model with Dymola.
  • Automated battery simulation processes, enhancing configurability and parameter creation capabilities through Python's multiprocessing pool.
  • Streamlined data management by automating data export and visualization in Excel using VBA, ensuring efficient and clear representation of battery analytics.
Technologies: Python, MATLAB, Back-end, Front-end, Graphical User Interface (GUI), Flask, REST, APIs, Git, SQL, Bitbucket, Engineering, Data Visualization, Data Engineering, CAD, 3D CAD, Scripting

Onemarkets Investment Platform by UniCredit
It is an investment platform for structured products. As a full-stack developer, I coordinated with trading and sales colleagues to produce scalable solutions to support business growth. I also evaluated the software designs of others and ensured that our software design balanced functional, quality, and security requirements.

Web App for Soil Analysis
As a full-stack developer working on this web app for soil analysis, I was responsible for designing and developing the front and back end using Angular and .NET technologies, respectively. The web app allows users to upload soil samples, analyze, and generate reports based on the results. I also ensured the app was secure, scalable, and optimized for performance.

Asset Management: Legal Document Processing Revolution

A revolutionary solution that leverages Azure OpenAI Service, incorporating a chatbot with bulk processing capabilities. This AI-driven system automates the extraction of key information from the bank's extensive legal documents, significantly enhancing the accuracy and speed of the tax liability identification process.
2013 - 2016

Master's Degree in Automotive Engineering

Technical University Braunschweig - Braunschweig, Germany

2009 - 2013

Bachelor's Degree in Automotive Engineering

Tongji University - Shanghai, China


REST APIs, Node.js, PrimeNG, React, SQLAlchemy, jQuery, API Development


Visual Studio, Redmine, MATLAB, Microsoft Dynamics CRM, Azure OpenAI Service, ChatGPT, Git, Jenkins, NPM, Bitbucket, Microsoft Dynamics, Microsoft Power Apps, PyCharm, Altova XML, CAD, Apache Tomcat, IntelliJ IDEA, Microsoft Power BI, Presentation Foundation


Angular, Flask, Windows Presentation Foundation (WPF), .NET 4, .NET, Selenium, ASP.NET, .NET Core, Windows PowerShell, ASP.NET Core MVC, NestJS


Java, Python, SQL, HTML, JavaScript, C#, C#.NET, TypeScript, CSS, XAML, C++, Batch


Visual Studio Code (VS Code), Mapbox, MacOS, Windows, Amazon Web Services (AWS), Oracle Database, Oracle, Microsoft Power Automate, WordPress, Windows Server, Docker, Java EE, Azure Functions, Kubernetes, Azure


Oracle SQL, PostgreSQL, PL/SQL, SQLite, Microsoft SQL Server, Databases, Redis, Elasticsearch


REST, Model View ViewModel (MVVM), Automation, Test Automation, Microservices, Microservices Architecture


WCF Web Services, Web Development, APIs, Back-end Development, Web Scraping, Scripting, Software Engineering, Back-end, Microsoft Dynamics 365, Dynamics CRM 365, Azure AI Search, Data Structures, Algorithms, Financials, IIS, Software Design, Front-end, Graphical User Interface (GUI), Full-stack, Web MVC, Stock Market, Stock Market Techinical Analysis, Troubleshooting, CI/CD Pipelines, Engineering, Data Visualization, Data Engineering, Stock Trading, Root Cause Analysis, Commerce, Architecture, API Integration, FastAPI, 3D CAD, Chatbots, OpenAI, Retrieval-augmented Generation (RAG), Mastercam

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