Four years solo, $12k MRR, and a stack that fits on one sticky note.

The first Stack of the Month is a solo founder who has been running a B2B product analytics tool for nearly four years. $12k MRR, around 800 paying users, no employees, no co-founder. They asked to stay anonymous. The interview below is lightly edited.

What runs the business day-to-day

"The shortlist is shorter than people expect. I open Notion (the entire ops layer lives there: client tracker, content planner, projects, the inbox for stray thoughts), Linear (issues for the product, even though it's overkill for one person), Stripe (revenue dashboard before coffee), and Vercel (deploy preview on every commit). The rest is what runs the product itself: Supabase for the database and auth, PostHog for the analytics that I actually trust, Resend for transactional email, Cloudflare for everything that touches the network, Sentry to know about errors before the user emails me, and Cursor as the editor I write in. That is the whole list."

A useful frame: the tools they open daily are different from the tools they pay for. The browser tabs that are always open are Notion, Stripe, and the Vercel dashboard. The product-running tools are mostly invisible until something breaks.

What they cut in the last six months

"Mailchimp went first. I was paying $40 a month for a list of 1,800 people, and the unsubscribe rate told me they were not paying attention. I moved the list to Resend with a tiny custom flow because I send maybe one broadcast a month. That alone saved me $500 a year and made the writing feel less performative. Airtable went next. I was using it for the user research tracker, which was overkill — Notion handled it with one extra database. Two subscriptions, gone, with no measurable downside."

The pattern across the cuts is the same: tools that solved a problem they no longer had. Mailchimp made sense when they were sending weekly. Airtable made sense when they were running structured research weekly. Six months without those rhythms meant six months of paying for nothing.

What they added

"PostHog replaced Mixpanel. I was on the legacy free tier and watching them slowly raise prices on the paid tiers. The self-host option clinched it: $5 a month on a Hetzner box, full ownership, session replay included. The migration took two evenings and the data quality is genuinely better. Sentry was the other addition — I had been running for three years without proper error monitoring, which sounds insane in retrospect. The first week with Sentry installed I found four silent errors that were probably causing churn."

Sentry is a recurring story in solo SaaS: a tool that feels unnecessary until you actually install it, and then is impossible to imagine running without.

The one decision they would re-do

"I would have moved off Mailchimp two years earlier. The sunk-cost feeling kept me on it for at least a year longer than it should have. The lesson is that subscriptions are not free even when they are paid: every month I kept it was a month of low-quality writing because I was performing for a list that was not engaged. The financial cost was the smallest part."

The whole stack, at last count

The full software bill, monthly:

• Notion: $10
• Linear: $0 (free tier still fits)
• Stripe: pay per transaction, not flat
• Vercel: $20
• Supabase: $25
• PostHog: $0 (self-hosted)
• Resend: $20
• Cloudflare: $0
• Sentry: $26
• Cursor: $20

Total fixed monthly: $121. Plus Stripe fees at a couple of percent of MRR. The stack would have cost something like $400 a year ago. Mailchimp + Airtable + Mixpanel was the difference.

The hidden thing

They block 9 AM to noon every weekday for deep work and refuse meetings before 2 PM. Cal.com enforces it. The stack just clears the friction; the discipline is what compounds.

Want yours profiled?

Use the Stack of the Month pitch form. Tell us your role, revenue band, and the three tools you would not give up. We pick one a month. Stays anonymous unless you ask otherwise. Scheduled pitches show up in the public queue so readers can see who is coming next.