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.

LLM Observability & EvalsFree tier

OpenTelemetry: Pricing, Features & Alternatives

OpenTelemetry is not a dashboard. It is the CNCF standard, SDKs and Collector that decide what a trace looks like and where it gets sent. Its GenAI semantic conventions now live in their own repository and cover spans, metrics and events for model clients, MCP and provider-specific calls (OpenAI, Anthropic, Bedrock, Azure AI). Instrument once with OTel and the traces can go to Langfuse, LangSmith, Braintrust or a Grafana stack you run yourself. That is why it belongs on this list: it is how you avoid getting locked into any of them.

OpenTelemetry Pricing Plans (2026)

Plan	Price	Highlights
Open sourcePopular	$0 (you run or choose the backend)	SDKs for every major language · OpenTelemetry Collector for routing and sampling · GenAI semantic conventions for LLM, agent and MCP spans

Pricing summary: Free. Always confirm current pricing on the official site.

Key OpenTelemetry Features

SDKs for every major language
OpenTelemetry Collector for routing and sampling
GenAI semantic conventions for LLM, agent and MCP spans
Export to any OTLP-compatible backend

Pros

+No vendor lock-in: switch backends without re-instrumenting
+One trace spans your API, database and model calls
+Every serious observability vendor accepts OTLP
+Apache 2.0 licensed, CNCF governed

Cons

−No UI, evals or prompt management of its own
−You still have to pick and pay for (or run) a backend
−GenAI conventions are still evolving, so attribute names can shift

Best OpenTelemetry Alternatives

Compare all

Langfuse

Free · paid from $29/mo

Braintrust

Free · paid from $249/mo

LangSmith

Free · paid from $39/seat/mo

OpenTelemetry Compared

OpenTelemetry vs Langfuse OpenTelemetry vs Braintrust OpenTelemetry vs LangSmith

OpenTelemetry FAQ

What is OpenTelemetry used for?⌄

OpenTelemetry is a llm observability & evals tool. The vendor-neutral standard for traces, metrics and logs, with GenAI conventions that describe LLM calls, agents and MCP in one shared schema.

Is OpenTelemetry free?⌄

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

How much does OpenTelemetry cost?⌄

OpenTelemetry is free to use.

What are the best OpenTelemetry alternatives?⌄

Popular OpenTelemetry alternatives include Langfuse, Braintrust, LangSmith. Compare pricing and features on our OpenTelemetry alternatives page.