The SaaS hackathon stack in one line
Next.js on Vercel + Supabase + Clerk + Stripe sandbox + Resend + PostHog, with Tough Tongue AI if your product needs a voice agent. All have free tiers, and together they give judges what a real SaaS shows: sign-up, the core workflow, a checkout and a welcome email.
Last updated: November 3, 2026 · 9-minute read · Free tiers checked on official pricing pages on November 3, 2026
A SaaS hackathon asks for more than a clever demo: judges want to see a product someone could sign up for and pay for. That means auth, a database, payments and email, which is a lot of plumbing for one weekend. The tools below remove most of it, so your team can spend its hours on the workflow that makes the product worth paying for.
New to hackathons? Start with our complete guide to hackathon tools. If your SaaS is AI-first, also read the best AI hackathon tools.
The SaaS hackathon stack at a glance
| Job | Tool | Free tier (checked Nov 2026) |
|---|---|---|
| Front end + host | Next.js on Vercel | Vercel Hobby: $0, personal and non-commercial use |
| UI generation | v0 | Free plan with a 7 message/day limit |
| Database | Supabase (or Neon) | Supabase: 500 MB DB, 50,000 MAUs, 2 active projects |
| Auth | Clerk (or Supabase Auth) | Clerk: 50,000 monthly retained users per app, no card |
| Payments | Stripe sandbox | Test payments that move no money |
| Resend | 3,000 emails/month, 100/day | |
| Analytics | PostHog | 1M events and 5K session recordings/month, no card |
| Voice agent | Tough Tongue AI | 25 free browser minutes |
| Demo video | Loom | 5-minute videos, 25 per person |
Front end and hosting: Next.js on Vercel
Deploy an empty Next.js app to Vercel in the first hour, then build on a live URL. Every push redeploys, so the judges' link is always current.
- Vercel Hobby is free for personal, non-commercial projects, with 1M function invocations and 100 GB of fast data transfer a month. Usage is capped on Hobby, which is fine for a prototype.
- v0 generates React and Tailwind UI from a prompt; the free plan allows 7 messages a day, so use it for the landing page and the main dashboard, then edit by hand.
Database: Supabase or Neon
Pick Supabase if you want database, auth and file storage in one project; pick Neon if you only need Postgres.
- Supabase Free includes a 500 MB database per project, 50,000 monthly active users and 2 active projects. Free projects pause after a week of inactivity, so open the dashboard before judging.
- Neon Free allows 100 projects with 1 GB of storage each; compute pauses after 5 minutes idle and wakes on the next query, which adds a short delay to the first request.
Model only the tables your demo touches: users, the core object (projects, invoices, bookings) and subscriptions.
Auth: Clerk or Supabase Auth
Clerk is the fastest way to get polished sign-in screens; Supabase Auth is the simplest if your data is already in Supabase.
- Clerk's free plan covers up to 50,000 monthly retained users per app, with no credit card required, and ships prebuilt sign-in and user-profile components.
- Supabase Auth comes with the Supabase project above, so users and data share one database and one set of access rules.
Turn on one social login (Google or GitHub) so judges can sign up in one click during the demo.
Payments: Stripe sandbox
Show a working checkout with Stripe test payments; it is the moment that makes a prototype look like a business.
A Stripe sandbox is an isolated test environment, and transactions in it do not move funds. Pay with the test card 4242 4242 4242 4242, any future expiry such as 12/34 and any three-digit CVC (Stripe testing docs). Stripe recommends using test PaymentMethods such as pm_card_visa in code rather than raw card numbers.
Keep it to one plan and one price. Use Stripe's hosted Checkout page rather than building a payment form, and listen for the checkout-completed webhook to mark the user as paid. Students also get $25 in Stripe fee credits through the GitHub Student Developer Pack.
Email: Resend
Send one transactional email (the welcome or receipt) so the product feels real. Resend's free plan allows 3,000 emails a month and 100 a day across 3 domains, which is plenty for a demo. Verify your sending domain early, because DNS changes can take time to propagate.
Analytics: PostHog
Add analytics on day one, and you can show judges real usage from other hackers testing your app. PostHog's free tier includes 1M analytics events and 5K session recordings a month, with no credit card required. A simple funnel (visited, signed up, completed core action, paid) makes a strong final slide.
Voice agent: Tough Tongue AI for onboarding, sales or support
A voice agent can be the feature that separates your SaaS from every other dashboard in the room. Instead of a help page, a new user talks to an agent that explains the product, qualifies the lead or walks them through setup.
Tough Tongue AI builds live voice agents for sales, onboarding, support and training, and you can embed them in your app as an iframe with microphone access.
- Build without wiring a pipeline. Describe the agent in ChatGPT or Claude through Tough Tongue AI's connector, then test it in the browser (Tough Tongue hackathon guide).
- Pass user context. The embed can take the user's name and custom variables, so the agent greets each signed-in user by name and knows their plan.
- Score every conversation. Sessions can be scored against a rubric, which gives your SaaS a built-in analytics story.
- Pricing. 25 free minutes in the browser; phone and meeting agents start on Starter at $20 a month, with 50% off for students with a .edu email (Tough Tongue pricing). Teams can apply for hackathon credits through a form, though there is no standard program.
SaaS ideas with a voice agent at the core: an AI sales-call trainer for small teams, an interview-practice tool for a niche role, an onboarding concierge for a B2B app, or an appointment-booking receptionist. You can see an embedded agent working on our free AI mock interview page.
What to cut in a 48-hour SaaS build
Judges score the core value and the demo, not feature completeness. Cut these without guilt:
- Admin panels and settings pages
- Team accounts, roles and invitations
- Multiple pricing tiers, coupons and real billing logic (keep one test checkout)
- Password reset flows (use social login)
- Mobile apps (a responsive web app is enough)
A 48-hour SaaS hackathon plan
This is the schedule we recommend; compress it for a 24-hour event.
| Hours | Deliverable |
|---|---|
| 0–3 | Problem, one-sentence pitch, demo flow sketch, repo |
| 3–8 | Next.js on Vercel, Supabase tables, Clerk sign-in |
| 8–28 | The core workflow, end to end, on the live URL |
| 28–34 | Stripe test checkout, welcome email via Resend |
| 34–40 | Voice agent or AI feature, PostHog funnel, landing page |
| 40–45 | Seed demo data, fix bugs, record a backup video |
| 45–48 | Final 2-minute demo video and submission |
Your SaaS hackathon is also a product-thinking interview
A SaaS hackathon project shows product sense, not just coding, which is exactly what product manager, GTM engineer and forward deployed engineer interviews probe. Be ready to explain who the customer is, why they would pay, what you cut and why, and what your analytics showed.
Practise that story with a free AI mock interview, add the project to an ATS-friendly resume with our resume builder, and review product manager interview questions if you are aiming for PM roles.
FAQ
What is the best tech stack for a SaaS hackathon?
Next.js on Vercel, Supabase, Clerk or Supabase Auth, Stripe sandbox, Resend and PostHog, plus Tough Tongue AI if the product needs a voice agent.
How do I demo payments in a hackathon without real money?
Use a Stripe sandbox with test keys: transactions do not move funds, and the test card 4242 4242 4242 4242 works with any future expiry and any three-digit CVC.
Which auth provider is best for a hackathon?
Clerk for the fastest prebuilt sign-in (free up to 50,000 monthly retained users per app), or Supabase Auth if your data is already in Supabase.
Can I build a SaaS product in a 48-hour hackathon?
You can build a convincing prototype with sign-in, one core workflow, a test checkout and a landing page. Cut admin panels, team accounts and real billing.
Is Vercel free for a hackathon project?
Yes. Vercel Hobby is free for personal, non-commercial projects. A product that starts taking real payments needs a paid plan.
Sources
Pricing and docs checked November 3, 2026: Vercel, v0, Supabase, Neon, Clerk, Stripe testing, Resend, PostHog, Loom, Tough Tongue AI pricing, Tough Tongue AI hackathon guide, GitHub Student Developer Pack.
Give your SaaS a voice
Build an onboarding, sales or support voice agent and embed it in your app. 25 free minutes to start.