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.

Background Jobs & WorkflowsFree tier

River: Pricing, Features & Alternatives

Name: App Stack Builder
Availability: InStock

River is an open-source (MPL-2.0) background job queue that stores jobs in Postgres or SQLite, enabling transactional enqueue alongside your application data. It started in Go and its site lists Go, Java, Ruby, Rust and TypeScript. The core is free; River Pro ($125/month) adds workflows, sequences, batching and concurrency limits.

Who it’s for: Go teams on PostgreSQL who want jobs enqueued in the same transaction as their data.

River at a Glance

What it is: Open-source job queue library
Languages: Go, Java, Ruby, Rust, TypeScript
What it runs on: Your Postgres or SQLite
How you pay: Free (MPL-2.0); optional Pro subscription
Free access: Full open-source library

Checked November 2026 against River, River Pro.

Visit River official site

River Pricing Plans (2026)

Plan	Price	Highlights
Open SourcePopular	$0 (self-hosted)	MPL-2.0 licensed · Runs on Postgres or SQLite · Transactional enqueue
River Pro	$125 / month	Workflows & sequences · Batching · Global concurrency limits

Pricing summary: Free · paid from $125/mo. Always confirm current pricing on the official site.

Key River Features

Open source under the MPL-2.0 license
Enqueues jobs transactionally in your existing database
Runs on Postgres and SQLite
Background jobs for Go, Java, Ruby, Rust and TypeScript, per the project site
River Pro: $125 a month; annual billing saves $300
Pro adds workflows, sequences, batching, global concurrency limits, a dead letter queue and encrypted jobs

Pros

+Idiomatic Go with strong typing
+Transactional enqueue on Postgres
+No separate broker needed
+Active development

Cons

−Go-first; other languages are newer
−Newer than incumbents
−Needs Postgres or SQLite

Best River Alternatives

Compare all

Temporal

Free · then usage-based

Inngest

Free · paid from $99/mo

Sidekiq

Free · paid from $99/mo

Trigger.dev

Free · paid from $10/mo

BullMQ

Free · paid from $139/mo

Graphile Worker

Free

River Compared

River vs Inngest River vs Sidekiq River vs Trigger.dev River vs BullMQ River vs Temporal River vs Graphile Worker

River FAQ

What is River used for?⌄

River is a background jobs & workflows tool. Fast, robust background job queue built on Postgres or SQLite with transactional enqueueing, Go-first with clients in other languages.

Is River free?⌄

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

How much does River cost?⌄

River offers a free tier, with paid plans starting at $125/month.

What are the best River alternatives?⌄

Popular River alternatives include Temporal, Inngest, Sidekiq, Trigger.dev, BullMQ. Compare pricing and features on our River alternatives page.