# n8n: Hacker News Launch Monitor with AI Ranking

> Watch HN's front page for competitor launches, YC batches, or keywords — get a ranked Slack digest with the ones actually worth reading.

**Platform:** n8n  
**Category:** n8n  
**Difficulty:** Beginner  
**Tags:** n8n, hackernews, monitoring, openai  
**Updated:** 2026-06-16  
**Source:** https://promptfoo.tech/workflows/n8n-hn-launch-monitor

## Overview
The HN front page is a firehose. This n8n workflow pulls the top 30 posts hourly, filters against your keyword and domain list, uses GPT-4o-mini to rank relevance and add a one-line summary, and posts a Slack digest twice a day. It's the fastest way to stop missing launches in your category.

## How it works
1. Cron trigger every 30 minutes.
2. Fetch HN top stories via Firebase API.
3. Function node dedupes against Postgres/Notion.
4. For matches, GPT-4o-mini writes: 1-line summary + relevance score (0-10).
5. Slack digest posts at 9am and 4pm with score >= 6 grouped by topic.

## Benefits
- Never miss a competitor launch by more than a few hours.
- Signal-to-noise beats browsing HN yourself.
- Runs on free tiers — HN API is public, GPT-4o-mini costs pennies.

## Use cases
- Founders in a fast-moving category (AI tools, dev tools, no-code).
- PMMs monitoring category trends.
- Investors watching batches from YC, S24, W25.

## Step-by-step
### Step 1: Load your keyword list
Include product names, category phrases, and 'Show HN' filters for a broad sweep.

### Step 2: Fetch and de-dupe
Store item.id in a small table; skip anything seen in the last 7 days.

### Step 3: Rank with GPT-4o-mini
Prompt: 'Given this HN title + URL description, rate 0-10 relevance to {my keywords} and write one line on why.'

### Step 4: Slack digest formatting
Group by topic; include HN link and score. Keep under 10 items per digest.

### Step 5: Tune weekly
Add a thumbs-up/thumbs-down reaction on Slack posts. Weekly, feed those back to refine the ranking prompt.

## Example
```
Digest: '[9/10] Show HN: Semantic search over your inbox (competitor to us) — clean UX, YC S25.'
```

## FAQs
**What about Product Hunt?**

Same pattern. Swap HN API for PH's GraphQL. Combine both into one digest.

**Why not just use HN's search alerts?**

They don't rank or summarize. This is HN + a signal filter, not a raw feed.

**Cost?**

Under $2/month for 30-item hourly runs on GPT-4o-mini.

---
Licensed under CC-BY-4.0. Attribution: PromptFoo.tech