The Micro-SaaS 90-Day Launch Checklist: From Idea to First Paying Customer

Most micro-SaaS founders fail not because they picked the wrong idea — they fail because they executed the right idea in the wrong order. They build for three months before talking to a single customer. They launch a landing page before they understand the problem. They obsess over pricing before they have one user who would pay anything at all.

This checklist exists to fix that. It is organized into three 30-day phases, each with a clear objective, a set of weekly deliverables, and explicit go/no-go gates that tell you whether to keep going or pivot before you waste another month.

This is not a motivational poster. It is a working document. Print it. Tape it to your wall. Check off lines.

Phase 1 (Days 1–30): Validate the Problem

Objective: Prove that a specific group of people has a painful, recurring problem they are actively trying to solve — and that your proposed solution fits how they think about it.

You ship zero code in Phase 1. If you are writing code in the first 30 days, you are ahead of the checklist and behind on validation.

Week 1: Define the Niche and the Problem

Day 1–2: Write a one-sentence problem statement

Before you open a browser, write this sentence by hand:

"[Target customer] struggles with [specific problem] because [root cause], which costs them [time/money/frustration]."

Examples of bad problem statements:

"Developers need better deployment tools." (Too broad)
"People lose time on email." (Too vague)

Examples of good problem statements:

"Freelance bookkeepers lose 4–6 hours per week manually reconciling QuickBooks entries for clients who pay late, because QuickBooks has no native late-payment workflow."
"Small gym owners lose 15–20% of monthly revenue to no-shows because their scheduling software sends generic reminders instead of personalized re-engagement messages."

The specificity of your problem statement determines the quality of every decision you make for the next 89 days.

Day 3–4: Map the existing solution landscape

Search for how your target customer currently solves the problem. Look for:

Direct competitors (products doing exactly what you plan to do)
Adjacent tools (products solving the problem partially or differently)
Manual workarounds (spreadsheets, Zapier automations, VA-assisted processes)
Forum threads where people ask "how do you handle X?"

Document what you find in a simple table: tool name, price, what it does, what it does not do. This becomes your competitive landscape document.

Day 5–7: Identify 20 people who have this problem right now

Not people who might have it someday. People who have it today.

Where to find them:

Reddit communities related to your niche (look for complaint threads)
LinkedIn searches for people with relevant job titles
Facebook Groups in your target vertical
Your own professional network
Slack communities and Discord servers in the space
Replies to relevant Twitter/X threads

You need 20 names and contact methods before the end of Week 1. This is not optional. If you cannot find 20 people who plausibly have the problem you are describing, the niche is either too narrow to be a business or too broad to be a useful target.

Week 1 Checklist:

[ ] One-sentence problem statement written
[ ] Competitive landscape table built (at least 5 tools/methods)
[ ] 20 prospective customers identified with contact methods
[ ] Go/No-Go Gate: Can you name 20 specific people who have this problem? If no, redefine the problem.

Week 2: Run Customer Discovery Conversations

Day 8–14: Conduct 10 customer discovery interviews

Your goal is not to pitch your idea. Your goal is to understand the problem from the inside.

The Rob Fitzpatrick "Mom Test" principle applies here: ask about their life, not your idea. Ask what they have already tried. Ask what it cost them. Ask how often it happens. Never ask if they would use your product.

A good 30-minute customer discovery script:

"Walk me through how you currently handle [problem area]." (5 min)
"What part of that process is most frustrating?" (3 min)
"How often does that frustration come up?" (2 min)
"What have you tried to fix it?" (5 min)
"What happened when you tried [their answer]?" (5 min)
"If you could wave a magic wand, what would the ideal outcome look like?" (5 min)
"Who else on your team or in your network deals with this same thing?" (referral ask, 5 min)

After each call, write three things in a document:

What they said verbatim (the most powerful quotes)
What they actually do (behavior, not intent)
What surprised you

Day 8–14: Track signal strength

After 10 interviews, grade your problem hypothesis:

| Signal | Strong | Weak | |--------|--------|------| | Problem frequency | "Every week" / "Every day" | "Sometimes" / "A few times a year" | | Current spend | Already paying for partial solutions | "I just live with it" | | Emotional intensity | Visible frustration, uses words like "nightmare" or "kills me" | Shrugs, seems indifferent | | Active search | "I've been looking for a solution" | "Never really thought about it" | | Referrals given | Refers 2+ people unprompted | Cannot think of anyone else |

If 7 of your 10 interviews show "weak" signals across the board, you do not have a problem worth building a business around. Pivot your problem statement before proceeding.

Week 2 Checklist:

[ ] 10 customer discovery calls completed
[ ] Call notes documented (verbatim quotes captured)
[ ] Signal strength scorecard completed
[ ] Go/No-Go Gate: Do at least 7 interviews show strong problem frequency AND emotional intensity? If no, revise your problem statement and repeat Week 2.

Week 3: Define the Solution and Test the Value Proposition

Day 15–18: Write the solution hypothesis

Based on your interviews, write a one-paragraph solution hypothesis:

"We will build a [type of tool] that helps [specific customer] [do specific thing] by [mechanism], which will eliminate [specific frustration] and save them [specific outcome]."

Then list the three features that are absolutely required for the solution to deliver that outcome — and nothing else. These are your Minimum Lovable Product features. Everything else goes on a "later" list.

Day 19–21: Build a smoke test landing page

A smoke test landing page is not a "coming soon" page. It is a real value proposition page with a call to action that would only be clicked by someone who genuinely wants what you are describing.

Required elements:

Headline: the outcome your customer wants, not what your product does
Sub-headline: who it is for and the mechanism
3 bullet points: the three core features from your solution hypothesis
Social proof placeholder: "Join [X] founders on the waitlist" (start at 0, update as you collect)
One CTA: "Get Early Access" or "Join the Waitlist" — captures email only
One pricing hint: "Launching at $49/month" (tests price sensitivity from day one)

Tools to use: Carrd ($19/year), Typedream (free tier), or a simple Next.js page deployed to Vercel in under 2 hours.

Day 22–24: Drive 100 targeted visitors to the page

Do not run ads yet. Drive targeted traffic manually:

Post in 3 relevant subreddits (follow subreddit rules — share the page as a "I'm building this" post, not an ad)
Share in 2 relevant Slack/Discord communities
Email the 20 people from your discovery list with a personal note
Post on LinkedIn with your personal story and the problem you are solving
DM 10 people on Twitter/X who fit the profile

Day 24–25: Measure the smoke test result

Your benchmark: a 15% or higher email capture rate from targeted traffic is a strong signal. Below 5% means your headline or value proposition is not landing.

If you sent 100 targeted visitors and captured fewer than 5 emails, do not assume the traffic was wrong. Assume the message is wrong. Rewrite the headline and repeat.

Week 3 Checklist:

[ ] Solution hypothesis written (3 core features defined)
[ ] Smoke test landing page live
[ ] 100+ targeted visitors driven to the page
[ ] Email capture rate measured
[ ] Go/No-Go Gate: Is email capture rate above 10%? If no, rewrite value proposition and rerun. Do not proceed to building until this gate passes.

Week 4: Lock the Spec, Set Up Infrastructure

Day 25–28: Write the one-page product spec

Not a 40-page PRD. One page. It contains:

Problem (one sentence)
Target customer (one sentence, specific)
Core use case (the one workflow your product must nail)
Three required features (from Week 3)
Out of scope for v1 (list everything you will not build yet)
Success metric for launch (e.g., "10 paying customers within 30 days of launch")
Technical stack decision (your language, framework, database, hosting — decided, not debated)

Day 29–30: Set up your development environment and infrastructure

Set up repository (GitHub or GitLab)
Set up hosting environment (Railway, Render, Fly.io, or Vercel + PlanetScale are fast for solo founders)
Set up Stripe account and create your first product and price
Set up error monitoring (Sentry free tier)
Set up basic analytics (Plausible or PostHog free tier)
Set up a customer email tool (Resend or Postmark for transactional, ConvertKit free for marketing)
Create a private Slack channel or Notion doc for your build log

Week 4 Checklist:

[ ] One-page product spec written and locked
[ ] Technical stack decided (no more deliberating)
[ ] Repository created and initial commit made
[ ] Stripe account live with at least one product/price created
[ ] Error monitoring, analytics, and email tools configured
[ ] Go/No-Go Gate: Is your spec genuinely one page? If it is longer, cut it. If you are still debating the stack, pick one and move on.

Phase 2 (Days 31–60): Build the MVP

Objective: Build the minimum version of your product that delivers the core use case and allows you to collect payment. Nothing more.

Week 5–6: Core Feature Development

Days 31–44: Build only the three required features

Every day, start your session by re-reading your one-page spec. Every time you feel the urge to add a feature that is not on the spec, write it down in a "later" document and keep building.

Daily development ritual:

Write one failing test for what you are about to build (even if it is just a manual test scenario)
Build the feature
Confirm the test passes
Commit to your repository with a clear commit message
Write one sentence in your build log about what you built and what is next

Days 31–44: The "5-minute rule" for architecture decisions

Every time you face an architecture decision, give yourself 5 minutes to pick the simpler option and move on. The perfect architecture for a product with 0 customers is a liability, not an asset. The goal is a working product, not an elegant one.

For authentication: use Clerk, Auth0, or NextAuth. Do not roll your own. For payments: use Stripe Checkout. Do not build a custom billing system. For database: use Postgres on a managed service. Do not set up your own server. For file storage: use AWS S3 or Cloudflare R2. Do not build your own.

Core functionality checklist by Day 44:

[ ] User can sign up and log in
[ ] User can complete the core use case (the one workflow your product must nail)
[ ] User can see the outcome of the core use case
[ ] Basic error handling in place (no raw stack traces shown to users)
[ ] Data is persisted correctly (nothing lost on page refresh)

Week 7: Payments and Onboarding

Days 45–51: Build the payment flow

This is the most important week in the entire 90 days. If you cannot collect money, you do not have a business. Build this before you build anything else in Phase 2 that is not on your three-feature spec.

Stripe integration checklist:

[ ] Stripe Checkout session creation working in test mode
[ ] Webhook handler for checkout.session.completed event
[ ] Subscription status stored in your database
[ ] Feature gating: free users see the product but cannot complete core use case without subscribing (or offer a time-limited free trial)
[ ] Billing portal enabled (so customers can manage their own subscription)
[ ] Test the full flow: sign up → start trial → subscribe → access features → cancel → lose access

Days 48–51: Build the onboarding flow

Your onboarding has one job: get new users to their first "aha moment" in under 5 minutes.

The aha moment is the moment when a user first experiences the core value of your product. For a micro-SaaS, this is almost always the first time they see the output of the core use case with their own data.

Onboarding checklist:

[ ] Welcome screen: one sentence on what to do first
[ ] Empty states: when a user has no data yet, show them exactly what to do (not a blank screen)
[ ] First-run wizard: 2–3 steps maximum to configure the minimum required setup
[ ] Success state: clear visual confirmation when the core use case is completed
[ ] Follow-up email: triggered within 5 minutes of sign-up, contains one link to the most important thing they should do

Week 8: Testing and Invite List

Days 52–60: Invite 10 people from your waitlist to use the product

These are "beta users," but do not call them that. Call them "founding members" or "early access users." Language matters.

The invitation message:

"I've been building [product name] based partly on our conversation a few weeks ago. It's ready for a small group to try. I'd love your honest feedback — the brutal kind. Here's your personal access link: [link]. I'll check in with you in 3 days."

During this week:

Watch 2–3 users use the product via a screen share (use Loom's async feature or a live Zoom call)
Read every error in Sentry every morning
Read every session replay in PostHog or Hotjar every evening
Send a personal follow-up to every beta user after 48 hours: "Did you get to try it? What broke?"

Week 8 Checklist:

[ ] Payment flow tested end-to-end in Stripe test mode
[ ] Onboarding flow complete with empty states and first-run wizard
[ ] 10 beta users invited and using the product
[ ] At least 3 screen-share sessions conducted
[ ] Sentry errors reviewed daily
[ ] Go/No-Go Gate: Are beta users completing the core use case without asking for help? If more than half need hand-holding, fix the onboarding before proceeding to launch.

Phase 3 (Days 61–90): Launch and First Revenue

Objective: Get to 10 paying customers. Not 1,000 users. Not $10,000 MRR. Ten people who paid real money for your product.

Week 9: Pre-Launch Prep

Days 61–67: Collect feedback and fix the critical issues

After 7 days of beta access, you should have a clear list of:

Bugs that prevent users from completing the core use case (fix these immediately)
Confusion points in onboarding (fix these before launch)
Feature requests (log these, do not build them yet)
Positive reactions ("I love this because..." — capture these as testimonials with permission)

Days 61–67: Prepare launch assets

[ ] 3–5 testimonial quotes from beta users (real names, real companies)
[ ] 2–3 screenshots showing the product delivering the core value
[ ] Updated landing page with social proof section
[ ] Launch email drafted for your waitlist
[ ] Product Hunt draft page created (if relevant to your audience)
[ ] 5 Reddit posts drafted for relevant communities (personal story + product reveal)
[ ] 3 LinkedIn posts drafted (problem story, solution reveal, launch day post)

Week 10: Launch Week

Day 68: Soft launch to your waitlist

Email everyone on your waitlist. Personalize the first line based on anything you know about them. Subject line: "You asked for early access — it's ready."

The email:

One sentence reminding them why they signed up
What the product does (one sentence)
What you built specifically (3 bullets — the three core features)
One real testimonial from a beta user
The price and what the launch deal is (e.g., "Lock in $29/month forever — price goes to $49 in 14 days")
One link to the product

Day 70–75: Public launch channels

Post in order of expected conversion:

Reddit communities where you conducted research (personal post, not spam)
Relevant Slack/Discord communities (follow their rules for self-promotion)
LinkedIn (your personal network — personal story posts outperform company posts 10:1)
Hacker News "Show HN" post (Tuesday–Thursday morning for best visibility)
Product Hunt (if your audience is developers or early adopters)
Twitter/X thread telling the building story

Days 68–75: Personal outreach to 50 targeted prospects

This is the highest-leverage activity of the entire 90 days. Most founders skip it because it feels uncomfortable.

Send a personal message to 50 people who fit your ideal customer profile. Not a mass email. A personal message that references something specific about them.

Template:

"Hi [Name], I saw your post in [community] about struggling with [specific problem]. I built something that addresses exactly this — [product name] [one-sentence description]. Would you be willing to try it for free for two weeks and give me honest feedback? No strings attached."

Convert 10–20% of these to free trials. Convert 20–30% of free trials to paid. That math gets you to 1–4 paying customers from this channel alone.

Week 10 Checklist:

[ ] Waitlist email sent
[ ] Public launch posts live on at least 3 channels
[ ] 50 personal outreach messages sent
[ ] Stripe switched to live mode
[ ] First payment received (goal: at least 1 paying customer by Day 75)

Week 11–13: Iterate to 10 Paying Customers

Days 76–90: Talk to every single customer

You have paying customers now. Talk to all of them. Schedule a 20-minute call with each one within 3 days of their first payment.

Ask:

"What made you decide to pay?" (understanding your true value prop)
"What almost stopped you from signing up?" (understanding friction)
"What would make you recommend this to a colleague?" (understanding the referral trigger)
"What is the one thing that, if we added it, would make this a no-brainer to keep?" (roadmap signal)

Days 76–90: The 10-customer acquisition tracker

| Customer | Source | Acquisition Method | Days to Convert | Monthly Value | |----------|---------|--------------------|-----------------|---------------| | 1 | | | | | | 2 | | | | | | ... | | | | | | 10 | | | | |

Fill this in as customers come in. By Day 90, you will know exactly which acquisition channels work for your specific product. This data is worth more than any market research report.

Days 76–90: The retention check

At Day 90, look at your cohort:

How many customers signed up in Week 10?
How many of them are still active in Week 13?
What is your Day-30 retention rate?

If retention is below 60%, you have a product-market fit problem that more acquisition will not fix. Fix the product before scaling acquisition.

Final Phase 3 Checklist:

[ ] 10 paying customers achieved
[ ] Customer call conducted with every paying customer
[ ] 10-customer acquisition tracker complete
[ ] Day-30 retention rate measured
[ ] Top 2 acquisition channels identified
[ ] Go/No-Go Gate for scaling: Is Day-30 retention above 60%? Is NPS above 30? Are customers referring others? If all three are yes, you are ready to invest in growth. If not, extend Phase 3 by 30 days and fix the product.

The Master 90-Day Checklist (Summary)

Phase 1: Validate (Days 1–30)

[ ] Problem statement written (specific customer, specific problem, specific cost)
[ ] Competitive landscape mapped (5+ alternatives)
[ ] 20 prospective customers identified
[ ] 10 customer discovery interviews conducted
[ ] Signal strength scorecard: 7+ strong signals
[ ] Solution hypothesis written (3 core features only)
[ ] Smoke test landing page live
[ ] 100+ targeted visitors driven
[ ] Email capture rate above 10%
[ ] One-page product spec written and locked
[ ] Full technical infrastructure configured

Phase 2: Build (Days 31–60)

[ ] All three core features built
[ ] Authentication working
[ ] Core use case completable end-to-end
[ ] Stripe payment flow working in test mode
[ ] Onboarding with empty states and first-run wizard
[ ] 10 beta users invited and active
[ ] 3+ screen-share sessions completed
[ ] Critical bugs fixed before launch

Phase 3: Launch (Days 61–90)

[ ] 3–5 testimonials collected from beta users
[ ] Landing page updated with social proof
[ ] Waitlist email sent
[ ] Public launch on 3+ channels
[ ] 50 personal outreach messages sent
[ ] Stripe switched to live mode
[ ] First payment received
[ ] Customer calls with all paying customers
[ ] 10 paying customers achieved
[ ] Day-30 retention measured

Common Failure Modes (And How to Avoid Them)

Failure Mode 1: Building before validating The symptom: You have a product but no customers. You keep adding features hoping one will be the thing that makes people pay. The fix: Stop building. Book 10 customer calls this week. Go back to Week 2.

Failure Mode 2: Validating with the wrong question The symptom: Everyone in your interviews says "yes, that sounds useful" but nobody converts when you launch. The fix: You asked "would you use this?" instead of observing what they actually do. Re-run interviews using the Mom Test. Only count votes that come with a wallet.

Failure Mode 3: The feature creep death spiral The symptom: You are on Day 75 and still "almost done" with the MVP. The fix: Reread your one-page spec. Delete anything that is not one of the three required features. Ship a version that only does those three things.

Failure Mode 4: Launching to no one The symptom: You launch and get zero response. The fix: You skipped the personal outreach. 50 personal messages sent this week, no exceptions.

Failure Mode 5: Winning vanity metrics The symptom: You have 500 waitlist signups and zero paying customers. The fix: The goal was never signups. The goal is 10 paying customers. Switch all energy to conversion. Charge your waitlist.

What "Done" Looks Like at Day 90

At the end of 90 days, you should have:

Ten paying customers
A clear understanding of which 1–2 acquisition channels brought those customers
A Day-30 retention rate above 60%
A list of the top 3 features your customers want next (from your customer calls)
A product that delivers the core use case reliably, without you manually intervening
A number: your MRR. Even if it is $290 or $490, it is a real number that proves a real business.

The first 90 days are not about building the perfect product. They are about proving that someone will pay you to solve a specific problem. Everything after Day 90 is about doing that at scale.

Build the checklist. Work the checklist. Ship.

This is not a motivational poster. It is a working document. Print it. Tape it to your wall. Check off lines.

Phase 1 (Days 1–30): Validate the Problem

Objective: Prove that a specific group of people has a painful, recurring problem they are actively trying to solve — and that your proposed solution fits how they think about it.

You ship zero code in Phase 1. If you are writing code in the first 30 days, you are ahead of the checklist and behind on validation.

Week 1: Define the Niche and the Problem

Day 1–2: Write a one-sentence problem statement

Before you open a browser, write this sentence by hand:

"[Target customer] struggles with [specific problem] because [root cause], which costs them [time/money/frustration]."

Examples of bad problem statements:

"Developers need better deployment tools." (Too broad)
"People lose time on email." (Too vague)

Examples of good problem statements:

"Freelance bookkeepers lose 4–6 hours per week manually reconciling QuickBooks entries for clients who pay late, because QuickBooks has no native late-payment workflow."
"Small gym owners lose 15–20% of monthly revenue to no-shows because their scheduling software sends generic reminders instead of personalized re-engagement messages."

The specificity of your problem statement determines the quality of every decision you make for the next 89 days.

Day 3–4: Map the existing solution landscape

Search for how your target customer currently solves the problem. Look for:

Direct competitors (products doing exactly what you plan to do)
Adjacent tools (products solving the problem partially or differently)
Manual workarounds (spreadsheets, Zapier automations, VA-assisted processes)
Forum threads where people ask "how do you handle X?"

Document what you find in a simple table: tool name, price, what it does, what it does not do. This becomes your competitive landscape document.

Day 5–7: Identify 20 people who have this problem right now

Not people who might have it someday. People who have it today.

Where to find them:

Reddit communities related to your niche (look for complaint threads)
LinkedIn searches for people with relevant job titles
Facebook Groups in your target vertical
Your own professional network
Slack communities and Discord servers in the space
Replies to relevant Twitter/X threads

Week 1 Checklist:

[ ] One-sentence problem statement written
[ ] Competitive landscape table built (at least 5 tools/methods)
[ ] 20 prospective customers identified with contact methods
[ ] Go/No-Go Gate: Can you name 20 specific people who have this problem? If no, redefine the problem.

Week 2: Run Customer Discovery Conversations

Day 8–14: Conduct 10 customer discovery interviews

Your goal is not to pitch your idea. Your goal is to understand the problem from the inside.

A good 30-minute customer discovery script:

"Walk me through how you currently handle [problem area]." (5 min)
"What part of that process is most frustrating?" (3 min)
"How often does that frustration come up?" (2 min)
"What have you tried to fix it?" (5 min)
"What happened when you tried [their answer]?" (5 min)
"If you could wave a magic wand, what would the ideal outcome look like?" (5 min)
"Who else on your team or in your network deals with this same thing?" (referral ask, 5 min)

After each call, write three things in a document:

What they said verbatim (the most powerful quotes)
What they actually do (behavior, not intent)
What surprised you

Day 8–14: Track signal strength

After 10 interviews, grade your problem hypothesis:

If 7 of your 10 interviews show "weak" signals across the board, you do not have a problem worth building a business around. Pivot your problem statement before proceeding.

Week 2 Checklist:

[ ] 10 customer discovery calls completed
[ ] Call notes documented (verbatim quotes captured)
[ ] Signal strength scorecard completed
[ ] Go/No-Go Gate: Do at least 7 interviews show strong problem frequency AND emotional intensity? If no, revise your problem statement and repeat Week 2.

Week 3: Define the Solution and Test the Value Proposition

Day 15–18: Write the solution hypothesis

Based on your interviews, write a one-paragraph solution hypothesis:

"We will build a [type of tool] that helps [specific customer] [do specific thing] by [mechanism], which will eliminate [specific frustration] and save them [specific outcome]."

Day 19–21: Build a smoke test landing page

A smoke test landing page is not a "coming soon" page. It is a real value proposition page with a call to action that would only be clicked by someone who genuinely wants what you are describing.

Required elements:

Headline: the outcome your customer wants, not what your product does
Sub-headline: who it is for and the mechanism
3 bullet points: the three core features from your solution hypothesis
Social proof placeholder: "Join [X] founders on the waitlist" (start at 0, update as you collect)
One CTA: "Get Early Access" or "Join the Waitlist" — captures email only
One pricing hint: "Launching at $49/month" (tests price sensitivity from day one)

Tools to use: Carrd ($19/year), Typedream (free tier), or a simple Next.js page deployed to Vercel in under 2 hours.

Day 22–24: Drive 100 targeted visitors to the page

Do not run ads yet. Drive targeted traffic manually:

Post in 3 relevant subreddits (follow subreddit rules — share the page as a "I'm building this" post, not an ad)
Share in 2 relevant Slack/Discord communities
Email the 20 people from your discovery list with a personal note
Post on LinkedIn with your personal story and the problem you are solving
DM 10 people on Twitter/X who fit the profile

Day 24–25: Measure the smoke test result

Your benchmark: a 15% or higher email capture rate from targeted traffic is a strong signal. Below 5% means your headline or value proposition is not landing.

If you sent 100 targeted visitors and captured fewer than 5 emails, do not assume the traffic was wrong. Assume the message is wrong. Rewrite the headline and repeat.

Week 3 Checklist:

[ ] Solution hypothesis written (3 core features defined)
[ ] Smoke test landing page live
[ ] 100+ targeted visitors driven to the page
[ ] Email capture rate measured
[ ] Go/No-Go Gate: Is email capture rate above 10%? If no, rewrite value proposition and rerun. Do not proceed to building until this gate passes.

Week 4: Lock the Spec, Set Up Infrastructure

Day 25–28: Write the one-page product spec

Not a 40-page PRD. One page. It contains:

Problem (one sentence)
Target customer (one sentence, specific)
Core use case (the one workflow your product must nail)
Three required features (from Week 3)
Out of scope for v1 (list everything you will not build yet)
Success metric for launch (e.g., "10 paying customers within 30 days of launch")
Technical stack decision (your language, framework, database, hosting — decided, not debated)

Day 29–30: Set up your development environment and infrastructure

Set up repository (GitHub or GitLab)
Set up hosting environment (Railway, Render, Fly.io, or Vercel + PlanetScale are fast for solo founders)
Set up Stripe account and create your first product and price
Set up error monitoring (Sentry free tier)
Set up basic analytics (Plausible or PostHog free tier)
Set up a customer email tool (Resend or Postmark for transactional, ConvertKit free for marketing)
Create a private Slack channel or Notion doc for your build log

Week 4 Checklist:

[ ] One-page product spec written and locked
[ ] Technical stack decided (no more deliberating)
[ ] Repository created and initial commit made
[ ] Stripe account live with at least one product/price created
[ ] Error monitoring, analytics, and email tools configured
[ ] Go/No-Go Gate: Is your spec genuinely one page? If it is longer, cut it. If you are still debating the stack, pick one and move on.

Phase 2 (Days 31–60): Build the MVP

Objective: Build the minimum version of your product that delivers the core use case and allows you to collect payment. Nothing more.

Week 5–6: Core Feature Development

Days 31–44: Build only the three required features

Every day, start your session by re-reading your one-page spec. Every time you feel the urge to add a feature that is not on the spec, write it down in a "later" document and keep building.

Daily development ritual:

Write one failing test for what you are about to build (even if it is just a manual test scenario)
Build the feature
Confirm the test passes
Commit to your repository with a clear commit message
Write one sentence in your build log about what you built and what is next

Days 31–44: The "5-minute rule" for architecture decisions

Core functionality checklist by Day 44:

[ ] User can sign up and log in
[ ] User can complete the core use case (the one workflow your product must nail)
[ ] User can see the outcome of the core use case
[ ] Basic error handling in place (no raw stack traces shown to users)
[ ] Data is persisted correctly (nothing lost on page refresh)

Week 7: Payments and Onboarding

Days 45–51: Build the payment flow

Stripe integration checklist:

[ ] Stripe Checkout session creation working in test mode
[ ] Webhook handler for checkout.session.completed event
[ ] Subscription status stored in your database
[ ] Feature gating: free users see the product but cannot complete core use case without subscribing (or offer a time-limited free trial)
[ ] Billing portal enabled (so customers can manage their own subscription)
[ ] Test the full flow: sign up → start trial → subscribe → access features → cancel → lose access

Days 48–51: Build the onboarding flow

Your onboarding has one job: get new users to their first "aha moment" in under 5 minutes.

Onboarding checklist:

[ ] Welcome screen: one sentence on what to do first
[ ] Empty states: when a user has no data yet, show them exactly what to do (not a blank screen)
[ ] First-run wizard: 2–3 steps maximum to configure the minimum required setup
[ ] Success state: clear visual confirmation when the core use case is completed
[ ] Follow-up email: triggered within 5 minutes of sign-up, contains one link to the most important thing they should do

Week 8: Testing and Invite List

Days 52–60: Invite 10 people from your waitlist to use the product

These are "beta users," but do not call them that. Call them "founding members" or "early access users." Language matters.

The invitation message:

"I've been building [product name] based partly on our conversation a few weeks ago. It's ready for a small group to try. I'd love your honest feedback — the brutal kind. Here's your personal access link: [link]. I'll check in with you in 3 days."

During this week:

Watch 2–3 users use the product via a screen share (use Loom's async feature or a live Zoom call)
Read every error in Sentry every morning
Read every session replay in PostHog or Hotjar every evening
Send a personal follow-up to every beta user after 48 hours: "Did you get to try it? What broke?"

Week 8 Checklist:

[ ] Payment flow tested end-to-end in Stripe test mode
[ ] Onboarding flow complete with empty states and first-run wizard
[ ] 10 beta users invited and using the product
[ ] At least 3 screen-share sessions conducted
[ ] Sentry errors reviewed daily
[ ] Go/No-Go Gate: Are beta users completing the core use case without asking for help? If more than half need hand-holding, fix the onboarding before proceeding to launch.

Phase 3 (Days 61–90): Launch and First Revenue

Objective: Get to 10 paying customers. Not 1,000 users. Not $10,000 MRR. Ten people who paid real money for your product.

Week 9: Pre-Launch Prep

Days 61–67: Collect feedback and fix the critical issues

After 7 days of beta access, you should have a clear list of:

Bugs that prevent users from completing the core use case (fix these immediately)
Confusion points in onboarding (fix these before launch)
Feature requests (log these, do not build them yet)
Positive reactions ("I love this because..." — capture these as testimonials with permission)

Days 61–67: Prepare launch assets

[ ] 3–5 testimonial quotes from beta users (real names, real companies)
[ ] 2–3 screenshots showing the product delivering the core value
[ ] Updated landing page with social proof section
[ ] Launch email drafted for your waitlist
[ ] Product Hunt draft page created (if relevant to your audience)
[ ] 5 Reddit posts drafted for relevant communities (personal story + product reveal)
[ ] 3 LinkedIn posts drafted (problem story, solution reveal, launch day post)

Week 10: Launch Week

Day 68: Soft launch to your waitlist

Email everyone on your waitlist. Personalize the first line based on anything you know about them. Subject line: "You asked for early access — it's ready."

The email:

One sentence reminding them why they signed up
What the product does (one sentence)
What you built specifically (3 bullets — the three core features)
One real testimonial from a beta user
The price and what the launch deal is (e.g., "Lock in $29/month forever — price goes to $49 in 14 days")
One link to the product

Day 70–75: Public launch channels

Post in order of expected conversion:

Reddit communities where you conducted research (personal post, not spam)
Relevant Slack/Discord communities (follow their rules for self-promotion)
LinkedIn (your personal network — personal story posts outperform company posts 10:1)
Hacker News "Show HN" post (Tuesday–Thursday morning for best visibility)
Product Hunt (if your audience is developers or early adopters)
Twitter/X thread telling the building story

Days 68–75: Personal outreach to 50 targeted prospects

This is the highest-leverage activity of the entire 90 days. Most founders skip it because it feels uncomfortable.

Send a personal message to 50 people who fit your ideal customer profile. Not a mass email. A personal message that references something specific about them.

Template:

"Hi [Name], I saw your post in [community] about struggling with [specific problem]. I built something that addresses exactly this — [product name] [one-sentence description]. Would you be willing to try it for free for two weeks and give me honest feedback? No strings attached."

Convert 10–20% of these to free trials. Convert 20–30% of free trials to paid. That math gets you to 1–4 paying customers from this channel alone.

Week 10 Checklist:

[ ] Waitlist email sent
[ ] Public launch posts live on at least 3 channels
[ ] 50 personal outreach messages sent
[ ] Stripe switched to live mode
[ ] First payment received (goal: at least 1 paying customer by Day 75)

Week 11–13: Iterate to 10 Paying Customers

Days 76–90: Talk to every single customer

You have paying customers now. Talk to all of them. Schedule a 20-minute call with each one within 3 days of their first payment.

Ask:

"What made you decide to pay?" (understanding your true value prop)
"What almost stopped you from signing up?" (understanding friction)
"What would make you recommend this to a colleague?" (understanding the referral trigger)
"What is the one thing that, if we added it, would make this a no-brainer to keep?" (roadmap signal)

Days 76–90: The 10-customer acquisition tracker

Fill this in as customers come in. By Day 90, you will know exactly which acquisition channels work for your specific product. This data is worth more than any market research report.

Days 76–90: The retention check

At Day 90, look at your cohort:

How many customers signed up in Week 10?
How many of them are still active in Week 13?
What is your Day-30 retention rate?

If retention is below 60%, you have a product-market fit problem that more acquisition will not fix. Fix the product before scaling acquisition.

Final Phase 3 Checklist:

[ ] 10 paying customers achieved
[ ] Customer call conducted with every paying customer
[ ] 10-customer acquisition tracker complete
[ ] Day-30 retention rate measured
[ ] Top 2 acquisition channels identified
[ ] Go/No-Go Gate for scaling: Is Day-30 retention above 60%? Is NPS above 30? Are customers referring others? If all three are yes, you are ready to invest in growth. If not, extend Phase 3 by 30 days and fix the product.

The Master 90-Day Checklist (Summary)

Phase 1: Validate (Days 1–30)

[ ] Problem statement written (specific customer, specific problem, specific cost)
[ ] Competitive landscape mapped (5+ alternatives)
[ ] 20 prospective customers identified
[ ] 10 customer discovery interviews conducted
[ ] Signal strength scorecard: 7+ strong signals
[ ] Solution hypothesis written (3 core features only)
[ ] Smoke test landing page live
[ ] 100+ targeted visitors driven
[ ] Email capture rate above 10%
[ ] One-page product spec written and locked
[ ] Full technical infrastructure configured

Phase 2: Build (Days 31–60)

[ ] All three core features built
[ ] Authentication working
[ ] Core use case completable end-to-end
[ ] Stripe payment flow working in test mode
[ ] Onboarding with empty states and first-run wizard
[ ] 10 beta users invited and active
[ ] 3+ screen-share sessions completed
[ ] Critical bugs fixed before launch

Phase 3: Launch (Days 61–90)

[ ] 3–5 testimonials collected from beta users
[ ] Landing page updated with social proof
[ ] Waitlist email sent
[ ] Public launch on 3+ channels
[ ] 50 personal outreach messages sent
[ ] Stripe switched to live mode
[ ] First payment received
[ ] Customer calls with all paying customers
[ ] 10 paying customers achieved
[ ] Day-30 retention measured

Common Failure Modes (And How to Avoid Them)

Failure Mode 4: Launching to no one The symptom: You launch and get zero response. The fix: You skipped the personal outreach. 50 personal messages sent this week, no exceptions.

What "Done" Looks Like at Day 90

At the end of 90 days, you should have:

Ten paying customers
A clear understanding of which 1–2 acquisition channels brought those customers
A Day-30 retention rate above 60%
A list of the top 3 features your customers want next (from your customer calls)
A product that delivers the core use case reliably, without you manually intervening
A number: your MRR. Even if it is $290 or $490, it is a real number that proves a real business.

The first 90 days are not about building the perfect product. They are about proving that someone will pay you to solve a specific problem. Everything after Day 90 is about doing that at scale.

Build the checklist. Work the checklist. Ship.