Alexis Bouchez

~ / startup analyses / 50 Open Source Ideas That Make Money

50 Open Source Ideas That Make Money

Open source and revenue are not at odds. Plausible, Cal.com, PostHog, Sentry, Mattermost, Supabase, n8n, Formbricks. All open source. All making real money. The trick is picking the right monetization pattern for the kind of software you are building.

This page lists 50 small software ideas that work as both. Five patterns, ten ideas each. Every one is buildable by a solo founder with a laptop and a Stripe account.

2. 1. Self host free, sell the cloud

The most reliable pattern for solo founders. You ship a single binary and good docs. Devs who love to tinker self host it. Everyone else pays you to run it for them. Pricing is usually $9 to $29 per month for individuals, more for teams.

  1. Tiny Cron Dashboard: run and monitor cron jobs via a single binary. OSS free. Cloud: $12/mo with SMS alerts on failure.
  2. Open Form Backend: receives form POSTs, emails you. OSS free. Cloud: $15/mo with spam filter, file uploads, Stripe forms.
  3. Open Waitlist: landing page plus referral waitlist. OSS free. Cloud: $9/mo with email automation and analytics.
  4. Open Changelog: one markdown file, one public page. OSS free. Cloud: $15/mo with email notifications to subscribers.
  5. Open Status Page: self host free. Cloud: $19/mo with SMS, Slack, and multi region checks.
  6. Open Docs: documentation site generator. OSS free. Cloud: $29/mo with PR previews, search analytics, and feedback.
  7. Open Kanban: solo focused board. OSS free. Cloud: $6/user/mo with team sync.
  8. Open Time Tracker: CLI plus web. OSS free. Cloud: $8/mo with team reports and invoicing export.
  9. Open Newsletter: mailer and archive site. OSS free. Cloud: $29/mo with managed deliverability and bounce handling.
  10. Open Bookmarks: Raindrop alternative. OSS free. Cloud: $4/mo with phone sync and full text search.

3. 2. Open core with paid team features

The free version is fully usable for individuals and small teams. You gate enterprise features: SSO, SAML, audit logs, RBAC, compliance, multi tenant. Big companies pay because they have to, not because the OSS version is crippled.

  1. Auth Kit: beautiful hosted auth pages. OSS free forever. Paid: SSO, SAML, audit logs, HIPAA. Starts $99/mo.
  2. Feature Flags: local first feature flag service. OSS free. Paid: multi env, A/B, audit logs. $49/mo.
  3. Job Queue: Sidekiq alternative with a dashboard. OSS free. Paid: multi queue metrics, priority, retention. $29/mo.
  4. Secret Manager: dotenv replacement. OSS free. Paid: team vault, audit, rotation, approval flows. $15/user/mo.
  5. Internal Tool Builder: Retool alternative. OSS free. Paid: SSO, RBAC, audit. $20/user/mo.
  6. OSS CRM: markdown contacts plus UI. OSS free. Paid: email sync, team dashboard, reporting. $12/user/mo.
  7. API Gateway: Kong lite. OSS free. Paid: multi tenant rate limits, customer portal. $99/mo.
  8. Metrics Dashboard: Grafana lite. OSS free. Paid: alerting, multi tenant, compliance. $49/mo.
  9. Self Hosted CI: GitHub Actions compatible runner. OSS free. Paid: fleet management, cost caps, pin enforcement. $15/user/mo.
  10. Backup Orchestrator: single script backups. OSS free. Paid: multi source, encryption, cross region replication. $29/mo.

4. 3. OSS client plus paid API

The tool runs locally and is useful on its own. A hosted API adds the premium features: AI, sync, data enrichment. Customers get the dignity of owning the client and the convenience of paying for the smart parts.

  1. Markdown Editor: local OSS editor. Paid API: AI edits plus cloud sync. $9/mo.
  2. SQL Client: OSS desktop client. Paid API: query explain and schema docs. $15/mo.
  3. AI Terminal: OSS terminal emulator. Paid API: command explain and generation. $10/mo.
  4. Regex Tool: OSS web tool. Paid API: natural language to regex. $5/mo.
  5. Image Optimizer: OSS CLI. Paid API: background removal and upscaling. Usage based.
  6. Static Site Generator: OSS. Paid API: image CDN, PR previews, search. $19/mo.
  7. Review VSCode Extension: OSS. Paid API: team semantic search. $15/seat.
  8. Markdown CRM: OSS file based contacts. Paid API: calendar sync and email enrichment. $10/mo.
  9. Dotfiles Manager: OSS. Paid API: encrypted cloud sync and backup. $3/mo.
  10. Password Manager: OSS local vault. Paid API: cross device sync. $3/mo.

5. 4. Dual license, free for OSS, paid for closed source

You release under AGPL or a similar copyleft license. Anyone can use it in an open source project. Companies who want to embed it in a closed source product buy a commercial license. Works best for libraries and components, not full apps.

  1. Realtime Collab Engine: CRDT library for editors and whiteboards. Commercial license $2k/yr.
  2. PDF Generator: headless HTML to PDF service. Commercial license $500/yr.
  3. OCR Pipeline: image to structured text. Commercial license $1k/yr.
  4. Image Processing Library: Sharp alternative. Commercial license $500/yr.
  5. Webhook Verifier: signing and replay protection library. Commercial license $300/yr.
  6. Email Parser: inbound email to structured data. Commercial license $500/yr.
  7. Audio Transcoder: opinionated FFmpeg wrapper. Commercial license $500/yr.
  8. PDF to Markdown: clean extraction for LLM pipelines. Commercial license $500/yr.
  9. Data Anonymizer: PII safe exports for testing and staging. Commercial license $1k/yr.
  10. HTML Diff Engine: semantic diff for HTML and markdown docs. Commercial license $500/yr.

6. 5. OSS platform with a transaction cut

The platform is OSS and fully self hostable. You run the canonical hosted version and take a small cut on transactions flowing through it. Your moat is the network effect of all the buyers and sellers meeting in your cloud version, not the code.

  1. OSS Sponsorships: GitHub Sponsors alternative, usable off GitHub. 5% cut.
  2. OSS Tipping Jar: Ko-fi alternative tailored to OSS maintainers. 5% cut.
  3. OSS Bug Bounty: lightweight bounty platform for OSS security reports. 10% of payouts.
  4. OSS Crowdfunding: Kickstarter for OSS projects. 5% cut.
  5. OSS Theme Marketplace: themes for OSS apps (Ghost, Hugo, Astro). 20% cut.
  6. OSS Merch Shop: per project merch stores for OSS communities. 20% cut.
  7. OSS Consulting Marketplace: pair clients with OSS maintainers. 15% cut.
  8. OSS Job Board: for shops using (or looking to hire for) specific OSS stacks. $99/post.
  9. OSS Invoicing: free invoice tool. Hosted payment handling takes 1%.
  10. OSS Subscription Billing: Stripe wrapper with an OSS dashboard. Hosted version takes 1%.

7. How to pick one

First pick the pattern, then pick the idea. The pattern decides the shape of the company: solo dev cloud, enterprise sales, API usage billing, license contracts, or marketplace ops. Each pattern has a different ideal customer and a different first year.

Self host plus cloud is the friendliest to a solo founder. Open core pays the best long term but needs SOC2 eventually. Paid API scales with usage without any sales calls. Dual license is lonely but lucrative for libraries. Marketplace is the hardest to bootstrap because you need both sides.

Pick the pattern that fits how you want to live for the next year. Then pick the idea where you can already see the first five stars on GitHub.