hackernews-intel

Monitor Hacker News for keywords. Get a Slack alert every time a new post matches your topics, without duplicates. Run it manually, on a cron schedule, or via GitHub Actions.

What It Does

• Fetches new posts from HN using the free Algolia search API (no API key needed)
• Checks each match against a local SQLite cache and never alerts on the same post twice
• Sends a Slack notification with title, URL, points, and comment count
• Supports dry-run mode to preview matches without sending alerts
• Configurable lookback window, minimum points threshold, and comment inclusion

Requirements

Requirement	Purpose	Where to Get It
HN_KEYWORDS	Keywords to monitor	Set in .env, comma-separated list
SLACK_WEBHOOK	Slack alerts	https://api.slack.com/apps, Incoming Webhooks
Node.js 20+	Running the script	https://nodejs.org

No API key needed for Hacker News. The HN Algolia API is free and public.

Setup

1. Install dependencies

cd hackernews-intel
npm install

2. Configure environment variables

cp .env.example .env

Edit .env:

HN_KEYWORDS=claude code,LLM agents,deno runtime
SLACK_WEBHOOK=https://hooks.slack.com/services/your/webhook/url
HN_MIN_POINTS=0

3. Create a Slack webhook

1. Go to https://api.slack.com/apps and create or select your app
2. Enable "Incoming Webhooks" in the app settings
3. Add a webhook to your workspace and select the target channel
4. Copy the webhook URL (starts with https://hooks.slack.com/services/)
5. Set it as SLACK_WEBHOOK in .env

How to Use

Preview the last 7 days without sending alerts:

npm run dry-run:week
# or
node scripts/monitor-hn.js --dry-run --days=7

Live run:

npm run monitor
# or
node scripts/monitor-hn.js

Schedule via cron (every 4 hours):

crontab -e
# Add:
0 */4 * * * cd /path/to/hackernews-intel && node scripts/monitor-hn.js >> /tmp/hn-intel.log 2>&1

Schedule via GitHub Actions:

name: HN Intel Monitor
on:
  schedule:
    - cron: '0 */4 * * *'
  workflow_dispatch:
jobs:
  monitor:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - uses: actions/setup-node@v4
        with:
          node-version: '20'
      - run: npm install
      - run: node scripts/monitor-hn.js
        env:
          HN_KEYWORDS: ${{ secrets.HN_KEYWORDS }}
          SLACK_WEBHOOK: ${{ secrets.SLACK_WEBHOOK }}

Add HN_KEYWORDS and SLACK_WEBHOOK as repository secrets.

Slack Alert Format

Each alert looks like:

Story Title Here
47 points  23 comments  authorname
Keyword: claude code  |  HN discussion

Options

Variable	Default	Purpose
HN_KEYWORDS	required	Comma-separated keywords
SLACK_WEBHOOK	required	Slack Incoming Webhook URL
HN_MIN_POINTS	0	Minimum points to alert
HN_INCLUDE_COMMENTS	false	Also monitor HN comments
HN_DB_PATH	./hn-intel.db	SQLite cache file path

CLI Flags

Flag	Purpose
--dry-run	Preview matches without sending Slack alerts
--days=N	Lookback window for the first run (default: 1)
--reset	Clear the cache and start fresh

GitHub Actions Note

GitHub Actions does not persist files between workflow runs. The SQLite cache resets on each run, and the script re-fetches the last 1 day of posts every time. Posts from the previous run will be alerted again.

To fix this, either:

• Store hn-intel.db in an S3 bucket and download/upload it around the script run
• Use a self-hosted runner with persistent storage
• Use a cron job on your own machine instead

Project Structure

hackernews-intel/
├── SKILL.md
├── README.md
├── .env.example
├── package.json
├── evals/
│   └── evals.json
└── scripts/
    └── monitor-hn.js

License

MIT