Fix Angular 20 + ASP.NET Web API 2 ERP Performance Issues (Post-Upgrade Slowdown)

We recently upgraded our ERP system's frontend to Angular 20.3.19 and backend to ASP.NET Web API 2 and .Net Framework 4.7.2 Since the upgrade, the application has become noticeably slower — page loads, data grids, and API response times have all degraded compared to the previous version. We're looking for an experienced full-stack developer (or a pair — one Angular specialist, one .NET specialist) to diagnose and fix the performance regression. Scope of Work • Profile the application to identify what's causing the slowdown (frontend rendering, change detection, bundle size, API latency, DB queries, etc.) • Review Angular 20 upgrade for breaking changes/misconfigurations (standalone components, zoneless change detection, signals migration, lazy loading, build config) • Provide a clear diagnosis report with root causes • Implement fixes and optimizations • Provide before/after performance benchmarks Requirements • Proven experience with Angular 17+ (ideally hands-on with Angular 20 signals/zoneless change detection) • Strong experience with ASP.NET, .Net Framework and Entity Framework Core performance tuning • Experience with ERP or other large, data-heavy enterprise applications • Familiarity with browser dev tools, Lighthouse, Angular DevTools, and .NET profiling tools (dotTrace, MiniProfiler, Application Insights, etc.) • Ability to work independently and communicate findings clearly Nice to Have • Experience migrating legacy Angular/.NET apps to newer major versions • Experience with SQL Server query optimization / indexing Deliverables • Diagnostic report (root cause analysis) • Fixed, tested, production-ready code • Documentation of changes made • Performance comparison (before vs. after) Budget & Timeline $100.00 with 2 weeks How to Apply Please include: 1. Relevant experience with Angular 20 and/or ASP.NET Core 5.x 2. A brief note on how you'd approach diagnosing a post-upgrade performance issue 3. Your estimated timeline and rate Current issue facing 01: 1. PDF Report Generation Performance Issue PDF reports are generated from the C# Web API using stored procedures, and the data is mapped into DTO models. The system uses PuppeteerSharp (v6.0) with Razor Engine (v3.10) and Chromium headless browser (CSHTML rendering) to generate PDF files. The generated PDF is returned to the frontend as a byte array for download. Current issue facing 02: PDF generation is slow, especially on the first request after application start. The first PDF generation takes significantly longer time compared to subsequent requests. After the first run, performance improves, but there is still noticeable delay. The delay occurs when the user clicks the “Generate Report” button, causing a waiting period before the PDF is returned. Current issue facing 03: User experience is affected due to waiting time before report download starts. This issue is observed across multiple modules where PDF reports are generated. 2. Address LOV (Lookup) Search Performance Issue in Forms The system uses multiple address-related dropdown (LOV) fields across different modules and forms. These fields include: CountryID ProvinceID / StateID CityID TownID CountyID Where this issue occurs: Profile form Profession form Property registration form Temporary user registration form Temporary profession registration form Property filter/search component Reusable address components used across multiple modules Implementation Details: The dropdowns are implemented using Angular mat-select. A custom search is implemented using a search input and Angular pipe. Data is loaded from the API based on selected parent IDs (countryId, provinceId, cityId, etc.). The API returns all matching records for the selected condition. Current issue facing 04: When the returned dataset is large (e.g., cities for a province/state containing ~10,000+ records), the UI becomes extremely slow. The mat-select dropdown becomes slow to open and in some cases unresponsive. Rendering large datasets in dropdowns causes significant performance degradation. This affects multiple forms and reusable components across the system. Impact: User interface becomes slow and unresponsive in forms containing address fields. Affects multiple modules due to shared reusable components. Performance issues become more severe with large datasets.

Project ID: 40571109