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.

AI Coding AssistantFree tier

OpenAI Codex: Pricing, Features & Alternatives

OpenAI Codex is an agentic coding system that can read, edit, and run code across your project. It ships as an open-source CLI, IDE extensions, and a cloud agent in ChatGPT, powered by GPT-5-Codex models. The CLI is free (bring your own API key); higher usage comes with ChatGPT Plus, Pro, and Business plans or API billing.

OpenAI Codex Pricing Plans (2026)

Plan	Price	Highlights
Codex CLIPopular	Free (open source, BYO API key)	Open-source terminal agent · Reads, edits & runs code · Bring your own OpenAI API key
ChatGPT Plus	$20 / month	Codex cloud agent in ChatGPT · GPT-5-Codex access · Generous usage limits
ChatGPT Pro	$200 / month	Highest Codex usage limits · Priority access · Best for heavy agentic workflows

Pricing summary: Free · paid from $20/mo. Always confirm current pricing on the official site.

Key OpenAI Codex Features

Open-source terminal agent
Reads, edits & runs code
Bring your own OpenAI API key
Works locally

Pros

+Powerful agentic, multi-file coding
+Open-source CLI is free
+Backed by GPT-5-Codex models
+CLI, IDE, and cloud options

Cons

−Best limits require ChatGPT Pro ($200/mo)
−API usage costs add up
−Less editor-integrated than Cursor

Best OpenAI Codex Alternatives

Compare all

Cursor

Free · paid from $20/mo

GitHub Copilot

Free · paid from $10/mo

Google Antigravity

Free

Windsurf

Free · paid from $15/mo

Gemini Code Assist

Free · paid from $22.8/mo

Claude Code

From $17/mo

OpenAI Codex Compared

OpenAI Codex vs Cursor OpenAI Codex vs Claude Code OpenAI Codex vs GitHub Copilot OpenAI Codex vs Google Antigravity OpenAI Codex vs Windsurf OpenAI Codex vs Gemini Code Assist

OpenAI Codex FAQ

What is OpenAI Codex used for?⌄

OpenAI Codex is a ai coding assistant tool. OpenAI’s agentic coding tool — a terminal CLI, IDE extension, and cloud agent powered by GPT-5-Codex models.

Is OpenAI Codex free?⌄

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

How much does OpenAI Codex cost?⌄

OpenAI Codex offers a free tier, with paid plans starting at $20/month.

What are the best OpenAI Codex alternatives?⌄

Popular OpenAI Codex alternatives include Cursor, GitHub Copilot, Google Antigravity, Windsurf, Gemini Code Assist. Compare pricing and features on our OpenAI Codex alternatives page.

Not sure if OpenAI Codex fits your stack?

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