Show HN: TopicRadar – Track trending topics across HN, GitHub, ArXiv, and more
MickolasJae Tuesday, January 20, 2026
Hey HN! I built TopicRadar to solve a problem I had with staying on top of what's trending in AI/ML without checking 7+ sites daily.
https://apify.com/mick-johnson/topic-radar
What it does: - Aggregates from HackerNews, GitHub, arXiv, StackOverflow, Lobste.rs, Papers with Code, and Semantic Scholar - One-click presets: "Trending: AI & ML", "Trending: Startups", "Trending: Developer Tools" - Or track custom topics (e.g., "rust async", "transformer models") - Gets 150-175 results in under 5 minutes
Built for the Apify $1M Challenge. It's free to try – just hit "Try for free" and use the default "AI & ML" preset.
Would love feedback on what sources to add next or features you'd find useful!
Summary
The article discusses Topic Radar, a tool that helps users discover trending topics and content on social media. It provides insights into popular discussions, emerging trends, and influential voices across various platforms, enabling users to stay informed and engage with relevant content.
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