WhatHappened: Hacker News summaries, heatmaps, and contrarian picks.

What it does

WhatHappened is a web tool that summarizes the top daily posts from Hacker News. For each story, it generates two versions: a technical TL;DR with three bullet points and a simplified "explain like I'm five" summary. The service also includes a Heat Meter that analyzes comment threads to surface the most contested or discussed topics. Users can browse these cards instead of navigating Hacker News directly.

Who it is for

The tool targets developers and tech professionals who read Hacker News but find the interface overwhelming or time-consuming. Readers who want to stay informed on technical topics but lack time to sort through vague post titles or lengthy comment sections are the primary audience. The ELI5 summaries also make the content accessible to non-technical people interested in what is trending in tech.

Pricing

The site does not show prices.

How it stands out

WhatHappened addresses a specific friction point: Hacker News readers spending significant time clicking through unclear titles or skimming flame wars to extract useful information. The dual-summary approach—technical and simplified—lets different user types consume the same content at their preferred level of detail. The Heat Meter adds a curation layer beyond standard sorting, highlighting which stories are generating the most discussion rather than just the most upvotes. This combination of AI-generated summaries and discussion analysis reduces the "wall of text" problem the founder identified.

What a founder should check

A competitor considering this space should verify three things. First, understand whether Hacker News users actually want a filtered interface or whether the direct HN experience and existing tools (like Hacker News search, RSS feeds, or newsletters like Hacker News Digest) already capture this demand. Switching costs may be low if users only need to remember one more URL. Second, check whether the Heat Meter analysis of comments delivers meaningfully different insights than simply sorting by comment count or reading the comments themselves. If users can extract the same value from HN directly in 30 seconds, the added layer may not retain users. Third, assess pricing sensitivity: many HN tools compete on free tiers, and monetization paths (premium summaries, ad-free access, or email digests) may face friction with a price-conscious developer audience already accustomed to free information sources.

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