The $0 SaaS Stack — How Solopreneurs Run Real Businesses for Free in 2026

You don't need funding to run a real SaaS. You need a credit card for domain renewal and the discipline to pick the right free tiers.

We run production software on $0 a month. Not a toy. Not a demo. Actual paying-customer software. The stack exists because every major infrastructure provider now offers a free tier generous enough to support a real business up to meaningful scale. What used to require a seed round now requires a Saturday.

Here's what that stack looks like, component by component.

Hosting is Cloudflare. Workers, Pages, R2, D1, KV, Queues. All of it has a free tier. Cloudflare Workers gives you 100,000 requests a day free. Pages is unlimited static requests. R2 gives you 10GB of storage and zero egress fees, which is the single biggest scam in cloud infrastructure that Cloudflare killed. A lot of startups pay AWS hundreds a month in S3 egress. You don't have to. The Cloudflare network also puts your app on 300+ points of presence globally by default, which means your users in Singapore get the same latency as your users in New York.

Auth is Clerk. Free up to 10,000 monthly active users. You get social login, MFA, user management, webhooks, session handling, and an admin dashboard that would take you a month to build. If you're charging $20 a month and you have 10,000 users, you're doing $200k MRR and can afford the upgrade. Until then, $0. Clerk also ships with prebuilt React components, so you wire up sign-in in 10 minutes instead of 10 days.

Data is Airtable for most early-stage products. Treat it as your backend. You get a real database with a visual editor, an API, webhooks, and a free tier that handles 1,000 records per base. When you outgrow it, move to Cloudflare D1 or Neon Postgres, both of which have generous free tiers. The key is to not reach for Postgres on day one when Airtable gets you to product-market fit faster. Speed-to-learning beats architectural purity at this stage.

"R2 gives you 10GB of storage and zero egress fees, which is the single biggest scam in cloud infrastructure that Cloudflare killed."

Email is Resend. 3,000 free sends a month, 100 a day. Clean API, great deliverability, built by people who understand developers. Transactional, notifications, welcome flows. All covered. You can also plug Resend into React Email for templated designs that don't look like they came out of 2009.

Payments is Stripe. Technically not free — they take their cut per transaction — but there's no monthly fee, no setup cost, no minimums. You pay only when you earn. That's the definition of aligned incentives. Stripe Checkout and Stripe Billing get you from zero to recurring revenue in a weekend.

Analytics is Plausible's free self-hosted option or PostHog's free tier up to 1M events a month. Both give you what Google Analytics gives you without selling your users' data. PostHog also bundles feature flags, session recording, and experiments, which you'd otherwise stitch together from three paid tools.

AI is the interesting one. You can run the entire AI layer of a modern SaaS on free tiers if you design it right. Cloudflare Workers AI has a free daily allotment. Groq's free tier is absurdly generous and gives you sub-second inference on open models. Google's Gemini 3.1 Pro — which leads multi-task reasoning as of April 2026 — has a free tier for developers. Combine them behind a simple routing layer and your AI costs stay at zero for a long time. For most applications, you route simple prompts to the cheapest option and reserve the expensive models for the 10% of queries that genuinely need them.

Error monitoring is Sentry's free tier. CDN is built into Cloudflare. Background jobs run on Cloudflare Queues. Search runs on Meilisearch cloud free tier or Algolia's community plan. Cron jobs run on Cloudflare Cron Triggers. File uploads go to R2. Every gap has a free answer if you know where to look.

The whole stack deploys with one command. Cloudflare Wrangler pushes your Worker, Pages auto-deploys from GitHub, Clerk and Stripe are config-only, and Airtable and Resend are API keys. You can go from empty repo to live product in an afternoon.

The mistake most first-time founders make is over-engineering the infrastructure before they have customers. They stand up Kubernetes clusters for an app that has 12 users. They pay for Vercel Pro when Cloudflare Pages would handle their traffic for free. They set up Postgres on RDS when a Google Sheet would work. Infrastructure cost is a signal of scale. Let scale earn the cost. Until then, the $0 stack is not a compromise. It's a competitive advantage.

There's also a philosophical point. When your fixed costs are zero, your runway is infinite. You stop thinking like a startup burning capital and start thinking like a craftsman shipping product. That changes what you build, who you build for, and how patient you can be. Founders who spend $2,000 a month on infrastructure before they have paying customers burn out on month six. Founders who spend $0 for the same period are still shipping updates on month twenty-four.

The other underrated benefit is that working within free tiers forces you to understand your architecture. You can't just throw money at a problem. You have to actually optimize the SQL query, the cache strategy, the API call pattern. That discipline becomes a moat later, because your competitors with venture money never learned it.

This stack isn't going to carry you to $100M ARR. It's going to carry you from zero to your first 1,000 paying customers, which is the part where most companies die. Solve that problem first. The rest is a good problem to have.

Start a free Cloudflare account and a free Clerk account this week, wire them together on a weekend, and ship something.

See /free-saas-guide for the $0/month stack walkthrough.