What is App Stack Builder?

App Stack Builder is a free AI-powered tool that helps founders and developers choose the right tech stack for their projects based on budget, app type, team size, and skill level.

What is the best tech stack for SaaS in 2026?

The best tech stack for SaaS in 2026 typically includes Next.js 16 for frontend, Supabase for database and auth, Vercel for hosting, Stripe for payments, and PostHog for analytics. App Stack Builder can generate a personalized recommendation based on your specific budget and requirements.

Is App Stack Builder free to use?

Yes, App Stack Builder is completely free to use. You can generate unlimited tech stack recommendations without any cost.

What types of apps can I build with the recommended stacks?

App Stack Builder supports various app types including SaaS applications, web apps, mobile apps, e-commerce stores, internal tools, and AI/ML products.

How much does a SaaS tech stack cost per month?

A modern SaaS tech stack can cost anywhere from $0-50/month for bootstrapped startups using free tiers, $100-300/month for growth-stage startups, to $500+/month for enterprise-ready infrastructure. App Stack Builder helps you find the best tools within your specific budget.

What is the best tech stack for solo founders?

For solo founders, we recommend Next.js + Vercel (free), Supabase (free tier), Supabase Auth (free), Stripe (pay as you go), and Plausible or PostHog for analytics. This stack can run your entire SaaS for under $50/month.

Can I export my tech stack recommendations?

Yes, you can export your tech stack recommendations as a PDF document or copy them to your clipboard. You can also share a link to your stack with others.

Notifications & RealtimeFree tier

Knock: Pricing, Features & Alternatives

Knock is the polished commercial take on the same problem Novu solves in the open. Its strengths are the workflow editor non-engineers can actually use, genuinely good batching and digest logic, and a preference centre that handles the per-user, per-channel matrix properly. The jump from a free developer tier to $250 is steep and is the main reason teams weigh it against self-hosting.

Knock Pricing Plans (2026)

Plan	Price	Highlights
Developer	$0	10,000 messages / month · 500 guide active users · Unlimited workflows
StarterPopular	$250 / month	50,000 messages / month · 2,500 guide active users · $0.005 per extra message
Enterprise	Custom	Volume or notified-user pricing · Unlimited environments

Pricing summary: Free · paid from $250/mo. Always confirm current pricing on the official site.

Key Knock Features

50,000 messages / month
2,500 guide active users
$0.005 per extra message

Pros

+Best-in-class batching and digests
+Preference centre handles the hard cases
+Workflow editor non-engineers can use
+Unlimited team members on every tier

Cons

−$0 to $250 is a very big step
−No self-hosted option
−Message overages add up quickly

Best Knock Alternatives

Compare all

Novu

Free · paid from $30/mo

Courier

Free

MagicBell

Free · paid from $249/mo

Knock Compared

Knock vs Novu Knock vs Ably Knock vs Courier Knock vs OneSignal Knock vs MagicBell Knock vs Pusher Channels

Knock FAQ

What is Knock used for?⌄

Knock is a notifications & realtime tool. Notification infrastructure as a service: cross-channel workflows, batching, user preferences and an in-app feed, without running any of it.

Is Knock free?⌄

Yes — Knock has a free tier you can start with, and paid plans for more usage and features.

How much does Knock cost?⌄

Knock offers a free tier, with paid plans starting at $250/month. Some plans are usage-based (pay-as-you-go).

What are the best Knock alternatives?⌄

Popular Knock alternatives include Novu, Courier, MagicBell. Compare pricing and features on our Knock alternatives page.

Not sure if Knock fits your stack?

Get a free, AI-powered tech stack tailored to your budget, app type, and team size — including the best notifications & realtime pick for you.

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