--- title: "Freelance — Ivan Kahl" description: "Articles by Ivan Kahl published on developer-focused company blogs and platforms." url: https://ivankahl.com/freelance/ --- # Freelance Tutorials, deep dives and guides on .NET, AI tooling, APIs and DevOps, written for developer-focused companies. ## 2026 20 Apr 2026 ### [Getting Started with Codex](https://dometrain.com/blog/getting-started-with-codex/) Install Codex, explore its core workflows and learn how OpenAI's coding agent can automate practical bug fixes. Dometrain 07 Apr 2026 ### [Getting Started with Claude Code](https://dometrain.com/blog/getting-started-with-claude-code/) Install Claude Code, understand its agentic workflow and start using it effectively in day-to-day development. Dometrain 27 Jan 2026 ### [How to Build and Consume MCP Servers in .NET](https://dometrain.com/blog/how-to-build-and-consume-mcp-servers-in-dotnet/) Build and consume stdio and HTTP MCP servers in .NET, connecting AI models to external tools and resources. Dometrain 20 Jan 2026 ### [Making the Most Out of Your Coding AI Assistant](https://dometrain.com/blog/making-the-most-out-of-your-coding-ai-assistant/) Improve your AI coding workflow with practical techniques for prompting, context management and complex tasks. Dometrain 15 Jan 2026 ### [Creating the Perfect `CLAUDE.md` for Claude Code](https://dometrain.com/blog/creating-the-perfect-claudemd-for-claude-code/) Create a focused `CLAUDE.md` that gives Claude Code the project context and guidance it needs to work reliably. Dometrain ## 2025 03 Nov 2025 ### [What's New in C# 14](https://dometrain.com/blog/whats-new-in-csharp-14/) Explore every new C# 14 feature, understand why each one matters and see how to apply it with practical examples. Dometrain 30 Jul 2025 ### [How to Rotate an IP Address](https://brightdata.com/blog/how-tos/how-to-rotate-an-ip-address) Compare manual, proxy-based and no-code IP rotation methods for avoiding blocks and CAPTCHAs while web scraping. Bright Data 25 Jun 2025 ### [How to Build a C# REST API Client](https://developers.amadeus.com/blog/building-a-c-rest-api-client) Build a robust C# REST API client that authenticates, sends requests and consumes the Amadeus travel APIs. Amadeus ## 2024 23 Nov 2024 ### [The Developer's Guide to JWT Storage](https://www.descope.com/blog/post/developer-guide-jwt-storage) Compare secure JWT storage options for web applications and learn how to prevent common token vulnerabilities. Descope 07 Nov 2024 ### [8 Effective Strategies for Handling Flaky Tests](https://about.codecov.io/blog/effective-strategies-for-handling-flaky-tests/) Learn eight practical strategies for identifying, managing and resolving flaky tests without hiding real failures. Codecov 06 Aug 2024 ### [How an Event-Driven Architecture Ensures App Speed and Scalability](https://web.archive.org/web/20250325084740/https://deploy.equinix.com/blog/event-driven-architecture-eda-for-real-time-scaled-apps/) Learn how event-driven architecture supports scalable real-time applications through a practical implementation example. Equinix 14 Jun 2024 ### [What Is Static Code Analysis?](https://www.sonarsource.com/learn/static-code-analysis/) Learn how static analysis detects bugs, security vulnerabilities and code inconsistencies without running your application. Sonar 14 Jun 2024 ### [How to Integrate Fingerprinting Into Your Svelte Application](https://fingerprint.com/blog/browser-fingerprinting-svelte/) Integrate Fingerprint's SDK into a Svelte application to identify visitors and help protect your site from fraud. Fingerprint 06 Jun 2024 ### [When to Use a Load Balancer, an API Gateway or Both](https://deploy.equinix.com/blog/how-api-gateways-differ-from-load-balancers-and-which-to-use/) Compare load balancers and API gateways, understand their roles and learn when an architecture should use both. Equinix 21 May 2024 ### [What Is a Webhook?](https://sendbird.com/developer/tutorials/what-is-a-webhook) Understand how webhooks work, follow a practical implementation example and compare event delivery with traditional APIs. Sendbird 14 May 2024 ### [How Not to Do Code Reviews](https://www.aviator.co/blog/how-not-to-do-code-reviews/) Identify code review habits that create engineering bottlenecks and learn how to build a healthier review process. Aviator 09 May 2024 ### [How to Integrate Fingerprinting Into Your C# Application](https://fingerprint.com/blog/browser-fingerprinting-csharp/) Integrate Fingerprint's SDK into a C# application to identify visitors and help protect your site from fraud. Fingerprint 25 Apr 2024 ### [Digitally Collect Signed Waivers with Dropbox Sign API](https://sign.dropbox.com/blog/digitally-collect-signed-waivers-with-dropbox-sign) Collect signed waivers with the Dropbox Sign API, then receive and store completed documents through webhooks. Dropbox Sign ## 2023 06 Dec 2023 ### [cURL POST Request Guide](https://brightdata.com/blog/how-tos/curl-post-request-guide) Learn to send POST requests with cURL, including request bodies, content types, authentication and custom headers. Bright Data 22 Oct 2023 ### [Guide to Using GPT-3 with Python](https://www.sensible.so/blog/guide-to-using-gpt-3-with-python) Build a Python application with GPT-3 and use it for text-heavy tasks such as summarization and content generation. Sensible 03 Oct 2023 ### [Exploring GitHub Actions Triggers](https://earthly.dev/blog/github-action-triggers/) Explore GitHub Actions triggers, filters and events to run the right automated CI/CD workflows at the right time. Earthly 24 May 2023 ### [Using OpenAPI and AsyncAPI Tags to Better Organize API Endpoints](https://bump.sh/blog/openapi-tags-organize-endpoints) Use OpenAPI and AsyncAPI tags to organize related endpoints and make large API contracts easier to navigate. Bump.sh 19 May 2023 ### [Web Scraping with Playwright and Node.js](https://brightdata.com/blog/how-tos/playwright-web-scraping) Use Playwright and Node.js to scrape dynamic websites, extract structured data and apply advanced browser techniques. Bright Data 15 May 2023 ### [Building with Financial Data Sets and APIs](https://web.archive.org/web/20230529123933/https://iexcloud.io/blog/building-with-financial-data-sets-and-apis) Learn how to evaluate financial data sets and APIs, then choose reliable market data for applications and analysis. IEX Cloud 08 Feb 2023 ### [The Best Microsoft SQL Server GUI Tools](https://web.archive.org/web/20230213164545/https://www.airplane.dev/blog/the-best-microsoft-sql-server-gui-tools) Compare popular Microsoft SQL Server GUI tools across query editing, database management and developer workflows. Airplane.dev 06 Feb 2023 ### [Guide to Webhooks with Examples from Jira](https://www.merge.dev/blog/guide-to-webhooks-with-examples-from-jira) Learn how webhooks connect systems through a practical Jira example, from event subscriptions to payload handling. Merge 25 Jan 2023 ### [Adding Google Login to Your Next.js 13 Application](https://clerk.com/blog/add-google-login-next13-app) Add Google Login to a Next.js 13 application and compare a custom implementation with using Clerk authentication. Clerk ## 2022 24 Oct 2022 ### [A Developer's Guide: Ghost vs WordPress](https://wordpress.com/blog/2022/10/24/a-developers-guide-ghost-vs-wordpress/) Compare WordPress and Ghost from a developer's perspective, including their architecture, features and trade-offs. WordPress 19 Oct 2022 ### [Build Your First App with Deno](https://stateful.com/blog/build-your-first-deno-app) Install Deno, explore its secure runtime and build a first application with modern JavaScript and TypeScript. Stateful 18 Aug 2022 ### [Capturing a Screenshot of a Webpage in ASP.NET Core](https://urlbox.com/website-screenshots-aspnetcore) Capture webpage screenshots from an ASP.NET Core application by integrating the Urlbox API without browser automation. Urlbox 29 Jul 2022 ### [How to Take a Screenshot of a Web Page with Rust](https://urlbox.com/website-screenshots-rust) Capture webpage screenshots from a Rust application using browser crates and the Urlbox screenshot API. Urlbox