Now accepting early access

Grow your newsletter
without paid ads.

Penflock matches indie newsletter writers for automated audience swaps — reach new readers who already love your niche, no cold pitching required.

Free to join · For newsletters under 50k subscribers

The Maker's Dispatch
12,400 subscribers
Indie Hacker Weekly
8,200 subscribers

Compatibility score: 94%

How it works

Three steps to your next 1,000 subscribers

STEP 01

Connect your Substack

Link your newsletter in 30 seconds. We pull your audience data to build your compatibility profile — no CSV exports needed.

STEP 02

Get matched with compatible newsletters

Our algorithm scores compatibility based on topic overlap, audience size similarity, and engagement patterns from real Substack data.

STEP 03

Run automated swaps

Approve a match, pick a date, and Penflock handles the rest — coordinating shoutouts, tracking results, and measuring subscriber lift.

Why Penflock

Built for solopreneurs, not growth teams

Compatibility Scoring

Every match is scored for audience overlap, topic alignment, and engagement quality. Stop guessing, start growing with data.

  • Real Substack audience data
  • Topic & tone matching
  • Size-appropriate partners

Automated Swaps

Set your preferences once. Penflock schedules, coordinates, and tracks swaps — you just approve matches and watch subscribers arrive.

  • One-click approvals
  • Automated scheduling
  • Growth tracking

No Cold Pitching

Ditch the awkward DMs and spreadsheets. Every partner has already opted in. No rejection, no chasing — just mutual growth.

  • Warm intros only
  • Both parties pre-consented
  • Zero awkward outreach
Join 0 newsletter writers already on the waitlist

Get early access to Penflock

Be first to grow when we launch. Free tier available forever.

No spam. Unsubscribe anytime. We respect your inbox.