johnoreilly.dev

What It Is

johnoreilly.dev is the personal technical blog of Irish mobile software engineer John O'Reilly. The author describes himself as a Kotlin Google Developer Expert and has long focused on Kotlin Multiplatform, Compose Multiplatform, Android, iOS, SwiftUI, and cross-platform architecture. The site is not a SaaS product or developer tool, but rather a high-quality developer content site, so it is best categorized under “developer tools/developer resources.”

Core Features

The site mainly offers technical articles and hands-on engineering notes, covering topics such as shared code with Kotlin Multiplatform, Compose Multiplatform UI across Android/iOS/Desktop/Web, interoperability between SwiftUI and Kotlin, and ecosystem components including Ktor, SQLDelight, Room, StateFlow, Koin, and kotlin-inject. In recent years, the content has also clearly expanded into AI engineering practices, such as using the Gemini API, Vertex AI, MCP Server, Google Agent Development Kit, Koog AI Agent, RAG/Embeddings, and related technologies in Kotlin projects. Articles typically include background context, implementation ideas, code snippets, and related GitHub examples, with a strong emphasis on practical engineering rather than generic introductions.

Pricing

The scraped content does not show any paywall, paid subscription, course sales, or consulting pricing. The blog content appears to be freely accessible, so its pricing model can be considered free public content.

Pros and Cons

The main advantage is its highly focused subject matter, making it especially suitable for keeping up with cutting-edge developments in the Kotlin Multiplatform ecosystem. The author has long maintained and iterated on the same series of sample projects, giving the articles continuity and helping readers understand technical migrations and library evolution. The content is clearly code-oriented, making it useful for developers with an existing technical foundation who want direct reference material.

The limitations are also clear: this is a personal blog and does not offer commercial-grade support, SLAs, structured courses, or Q&A services. The content is in English, which may be a barrier for Chinese-speaking developers. Its topics are concentrated around Kotlin and mobile cross-platform development, so frontend, backend, or general AI application users may get limited value from it. In addition, based on the scraped text, the site’s information architecture appears fairly simple, and its systematic learning paths and search capabilities are unclear.

Who It’s For

It is best suited for Android/Kotlin engineers, KMP explorers, mobile architects, and developers who want to integrate Gemini, Vertex AI, MCP, or AI Agents into Kotlin/Compose projects. Programming beginners may find the context-heavy articles relatively demanding and somewhat advanced.

Access in China

As a personal site using a .dev domain, the content itself does not appear to involve obviously restricted services, so it should generally be directly accessible. However, external resources referenced in the articles—such as Google AI Studio, Gemini, Vertex AI, GitHub, and X/Twitter—may be partially restricted in mainland China. Reading the blog should not be a major issue, but reproducing the experiments may require a proxy or alternative environment.