The Best Tech Stack for Startups in 2026: The Stack We Ship 80+ Products On

The Best Tech Stack for Startups in 2026: The Stack We Ship 80+ Products On#

By Vishvajit Pathak, Co-Founder, MarsDevs. Published April 17, 2026. Updated April 19, 2026.

TL;DR: Our 2026 MVP stack is Next.js 15 (App Router) + Node.js 22 with Fastify 5 + Postgres 16 via Supabase + Drizzle ORM + Clerk + Stripe + Vercel + Railway + OpenAI and Anthropic APIs + PostHog + Sentry + Resend. For AI-heavy backends we swap Fastify for FastAPI on Python 3.12. MarsDevs has shipped 80+ products across 12 countries since 2019, and this is the exact stack we build new startup MVPs on every week. One pick per layer. No "it depends." Full rationale, archetypes, and costs below.

The MarsDevs Default Stack for a 2026 MVP#

We build every new MVP on this stack unless there is a reason we cannot. Next.js 15 + Fastify 5 (or FastAPI) + Postgres 16 + Drizzle + Clerk + Stripe + Vercel + Railway + OpenAI + Anthropic + PostHog + Sentry + Resend + GitHub Actions. Fourteen layers, fourteen picks, zero hedging.

Most startup blog posts give you four options per layer and call that helpful. It is the opposite of helpful. A founder with 10 weeks of runway and no CTO cannot benchmark Remix against Next.js against Nuxt. They need the pick. Here is ours.

The committed picks (one per layer)#

That is the stack. The rest of this article is why each pick, when to deviate, what it costs, and what we think we will change for 2027.

Quotable: MarsDevs is a product engineering company that has shipped 80+ products across 12 countries since 2019. Our 2026 default stack for a new startup MVP is Next.js 15, Postgres 16, Clerk, Stripe, Vercel, OpenAI, and Anthropic.

Why We Stopped Rotating Our Stack Every Six Months#

We tried Remix on 3 projects in 2024. SvelteKit on 2. Nuxt 4 on 1. All 6 shipped. None convinced us to move our default. Here is the thing: the stack itself is rarely what makes a startup win or lose. Shipping speed is.

Rotating your stack every six months costs you in three places. First, your senior engineers relearn the edges instead of writing product. Second, your hiring pool shrinks. We can find a Next.js engineer in Pune, Bangalore, Lisbon, or Austin in a week. A Svelte engineer takes four times as long. Third, your bug tail is worse. Battle-tested paths have fewer sharp edges.

So we picked one stack and we defend it. We change a layer when the evidence forces us, not when a new tool trends on Hacker News. Drizzle replaced Prisma for us in late 2025 after three client projects hit Prisma migration issues in production. That was evidence. We did not replace Postgres with anything, because Postgres has 25 years of evidence behind it.

Quotable: Boring stacks ship faster. We ship boring stacks on purpose.

If you are a founder trying to evaluate whether your agency's stack pitch is sensible, here is the first question to ask. When did they last change a default, and why? "We moved off X in Q4 2024 after hitting Y in production on Z projects" is a real answer. "We use whatever is modern" is not.

Frontend: Why Next.js 15 + React 19 Is the Default#

We ship every new MVP frontend on Next.js 15 with the App Router, React 19, Tailwind CSS 4, and shadcn/ui. This is the tightest path from pnpm create to a production deploy in 2026.

Next.js 15 landed RSC as the default, Server Actions as stable, and a much better caching model than the 14.x line that burned people. We deploy it on Vercel, where Next.js is a first-party runtime target. The official Next.js 15 release notes{target="_blank"} document the changes if you want the primary source. What that means for your MVP: your first deploy is 6 minutes after git push, not 2 days of Kubernetes.

React 19's use() hook and form actions cut the amount of state management code we write by roughly 30%. The 2025 Stack Overflow Developer Survey{target="_blank"} still shows React as the most-used web framework at 39.5%, and Next.js as the most-loved meta-framework. Hiring follows usage. Your senior engineer pool is deepest here.

The UI layer: shadcn/ui + Tailwind CSS 4#

We stopped using component libraries that you install from npm (Material UI, Chakra, Mantine) for new builds. We use shadcn/ui, which copies the component source into your repo. You own the code. You change the code. There is no breaking v3-to-v4 migration that eats a sprint.

Tailwind CSS 4 is the utility layer. The v4 engine is ~3x faster and drops the config file for most use cases. Between shadcn and Tailwind, we assemble a full design system in 2 days instead of 2 weeks.

When we deviate#

• Pure marketing sites with no app: Astro 5. Faster static output, less JS.
• Client is a Vue shop: Nuxt 4. Fine framework, narrower hiring pool for us.
• Extreme perf constraint (under 100ms interactions on 2017 Android): SvelteKit. We have shipped this twice. Most startups do not need it.

Backend + API: Fastify 5 for Node Teams, FastAPI for AI-Heavy Backends#

Our backend decision rule is one sentence. Fastify 5 on Node 22 for TypeScript monorepos, FastAPI on Python 3.12 for anything where we are calling ML libraries or serving models. That covers 95% of startup backends.

Fastify beats Express on raw throughput by roughly 2x, has a first-class schema-validation story (JSON Schema plus TypeBox), and is mature enough to run in production without surprises. We use it with Node 22 LTS because LTS means security patches through 2027, which matches the lifetime of most MVP-to-Series-A timelines. Express still works. We just do not start there.

FastAPI is the default the moment a backend is going to call LangChain, PyTorch, HuggingFace, LlamaIndex, or any model-serving library. Python's ML ecosystem is not catching up to JS. It is the other way around, slower than the takes suggest. FastAPI's type hints plus Pydantic v2 give us the same DX as a TS API.

Why not NestJS, Rails 8, or Go?#

We respect all three. We do not pick them as our default.

• NestJS 11 is fine if your team wants Angular-style dependency injection. Our senior engineers write Fastify in half the code.
• Rails 8 is a genuinely great batteries-included framework. Most founder hiring in 2026 is TS or Python, not Ruby. Shipping speed on Rails is excellent; rehiring replacement engineers is not.
• Go 1.23 (Gin, Chi) earns its place when the workload is genuinely CPU-bound or sub-millisecond latency-sensitive. Fintech routing, real-time matching engines, high-frequency webhooks. Not your MVP API.

We also skip tRPC for anything that will have a non-TS client eventually. It is lovely inside a Next.js monorepo. It is a rewrite when your mobile team arrives.

Database and ORM: Postgres 16 + Drizzle (and pgvector When AI Is Involved)#

Postgres 16 with Drizzle ORM, hosted on Supabase for new builds, migrated to self-hosted or Neon when scale demands. This is the database layer for every MarsDevs MVP in 2026.

Postgres 16 handles everything most startups need through Series A: relational data, JSONB for schemaless fields, full-text search, pgvector for embeddings, LISTEN/NOTIFY for realtime. We have shipped one product with MongoDB in the last 18 months, and that was because the data was genuinely unknown at design time (a customer-configurable analytics tool). Every other build was Postgres.

Quotable: We use Postgres 16 by default. MongoDB only appears when the schema is genuinely unknown at design time, which happens on maybe 1 in 20 projects.

Why Drizzle replaced Prisma for us#

We shipped on Prisma for three years. In late 2025 we moved our default to Drizzle ORM after Prisma's migration engine hurt us on three separate production databases inside two months. Drizzle is SQL-first, has no binary runtime, and its types line up with actual database rows instead of a generated client.

Prisma is still fine for simpler schemas. For anything with complex joins, window functions, or custom SQL, Drizzle wins. If your team has not used Drizzle, Prisma is still a defensible pick. We just do not start new builds on it.

Supabase for the first 18 months#

Supabase is our default managed host. You get Postgres 16, auth, storage, realtime subscriptions, and row-level security in one billed service. The Supabase pricing page{target="_blank"} puts the Pro tier at $25/month plus usage, which is enough for most pre-Series-A SaaS.

We have shipped on Supabase and migrated two projects off it post-Series A to self-hosted Postgres when load patterns demanded custom tuning. That is a healthy migration path. You are not locked in. Supabase is Postgres.

pgvector beats a separate vector DB at MVP scale#

For AI-enabled products that need embeddings, we use pgvector inside the same Postgres 16 instance. One database, one backup, one connection pool. At under 10 million vectors, pgvector handles recall and latency well enough that a separate vector database is operational overhead you do not need. We reach for Pinecone, Weaviate, or Qdrant only above that threshold, and only after running recall benchmarks on our specific workload.

Auth: Clerk for Most Startups, Supabase Auth When Going End-to-End on Supabase#

Clerk is our default auth layer for Next.js startups in 2026. Supabase Auth is our default when the rest of the stack is already Supabase. Anything else needs a real reason.

Clerk costs $0 up to 10,000 MAU, then roughly $0.02 per MAU after. Auth0 starts around $0.07 per MAU at equivalent tiers. For a startup crossing 10K MAU, Clerk is 3x cheaper and you keep better Next.js DX, magic links, Google/GitHub SSO, organizations, and webhook hooks into your user table. We have integrated Clerk into 11 Next.js products. The slowest integration took 3 hours.

Supabase Auth makes sense when you are already using Supabase for the database. Single bill, same team, RLS works natively off the auth JWT. No need to sync user IDs across two systems.

When we deviate#

• Enterprise SSO / SAML / SOC 2 on day one: Auth0 or WorkOS. Clerk now supports SAML on its Business tier, but if your first 3 customers are Fortune 500, start where the buyer is comfortable.
• Must self-host auth: NextAuth.js (Auth.js v5). Works. More ops.
• Open-source trendline: We are piloting Better Auth on one internal project. Not a default yet.

Payments: Stripe or Nothing (and When Lemon Squeezy Saves You)#

Stripe is the answer for a 2026 startup. There is no real alternative. This is the shortest section in the article because there is nothing to debate.

Stripe Billing handles subscriptions, metered billing, upgrades, proration, dunning, tax via Stripe Tax, and the webhook model every engineer already knows. Stripe Connect handles marketplace payouts. Stripe Radar handles fraud. You can ship a full B2B SaaS billing flow on Stripe in 4 days.

The one legitimate exception is merchant-of-record (MoR). If you are a one-person global SaaS selling to 40 countries and you do not want to handle VAT, GST, and sales tax filings yourself, use Lemon Squeezy or Paddle. They take ~5% plus $0.50 per transaction instead of Stripe's ~2.9% plus $0.30, but they file the taxes for you. For most VC-backed startups with a finance function, Stripe plus Stripe Tax is cheaper and more flexible. For solo founders, MoR is worth the premium.

We have integrated Stripe into every SaaS we have shipped since 2019. If you need the longer guide on pricing models and per-seat vs usage-based billing, see our cost to build a SaaS application in 2026 piece.

AI Layer: OpenAI + Anthropic + LangGraph + pgvector#

For any AI-enabled product in 2026, our default stack is the OpenAI API for generalist calls, the Anthropic API (Claude Sonnet 4.5) for agentic and long-context workflows, LangGraph for orchestration, Vercel AI SDK for streaming UI, and pgvector for retrieval. We use both OpenAI and Anthropic in the same product routinely, routed by task.

This is the 2026 differentiator. Stacks that do not name AI layers are incomplete.

When we use which LLM vendor#

We run a simple routing rule inside most products.

The Anthropic API reference{target="_blank"} and OpenAI API reference{target="_blank"} are the primary sources you should read before shipping production calls. Both have prompt caching, streaming, and tool use. Both are stable APIs. Pick the model by task, not by vendor loyalty.

LangGraph vs calling the API directly#

Call the API directly for fewer than three chained prompts. Reach for LangGraph the moment you need tool use, memory across turns, multi-agent flows, or resumable runs. That is our rule.

LangGraph (the stateful layer on top of LangChain) is our orchestration default for agents. It has graph semantics, checkpointing, and a usable interrupt model. LlamaIndex is our pick when the entire product is retrieval-heavy (document Q&A, knowledge assistants), because its retrieval primitives are denser.

Why pgvector over Pinecone for most MVPs#

Same reasoning as the database section. One DB. A startup does not need a second cluster to back up, monitor, and pay for at 50,000 vectors. At 10M+ vectors or sub-50ms p99 retrieval on huge catalogs, evaluate Pinecone or Qdrant. Not before.

Model Context Protocol#

MCP (Model Context Protocol) is the emerging standard for exposing tools to LLMs. Both Anthropic and OpenAI now support MCP servers. We have started wrapping internal tools as MCP servers for agentic products. It is not mandatory in 2026. It will likely be the default in 2027.

For the full playbook on building an AI MVP in 2026, we have a dedicated guide. This section is the stack slice.

Infra and Deploy: Vercel + Railway Is the 2026 Default#

Vercel for Next.js frontends, Railway for backend services that need a Postgres next to them. That is our 2026 infra default for any pre-Series-A startup. AWS enters in year two, not year zero.

Vercel is the zero-config deploy for Next.js. Preview URLs on every PR, automatic edge caching, build-in-seconds, generous free tier. At MVP scale a Vercel Pro seat is $20/month and that covers most products until real traffic arrives. The Vercel pricing page{target="_blank"} documents the current bands.

Railway is our default for anywhere we need a Python API, a worker, a Postgres, a Redis, and a GitHub-linked deploy on one dashboard. It is the DX that Heroku used to have before it stopped being maintained. At under $20/month you can run a Fastify API plus Postgres plus Redis, enough for a pre-Series-A B2B SaaS.

Cost comparison at MVP-tier workload#

Rough monthly cost for an MVP running a Next.js frontend plus a Node or Python API plus Postgres plus Redis, serving ~10,000 MAU and ~500K requests/day. Numbers rounded to nearest $5.

When we jump to AWS#

We migrate to AWS (ECS Fargate + RDS + ALB, or EKS at scale) in three scenarios only. HIPAA or SOC 2 Type II forces it. Workload exceeds ~$500/month on Railway. A late-Series-A customer demands VPC peering. Pre-Series A, AWS is usually a founder-gun-pointed-at-foot.

Cloudflare Workers and Cloudflare Pages are worth mentioning for edge-first products. We have shipped two projects on Workers. Good runtime. Cold start is gone. The ecosystem gap is the limiter. Some Node libraries simply do not work, so you write more from scratch.

Observability: Sentry + PostHog Covers 90% of Startups Until Series B#

Sentry for error tracking, PostHog for product analytics, OpenTelemetry for instrumentation standard. That covers observability for most startups through Series B. Datadog and the enterprise tier can wait.

Sentry's free Developer plan is enough for most MVPs. The Sentry pricing page{target="_blank"} documents current tiers, and the Sentry for Startups program offers up to $50,000 in credits for eligible funded startups. Sign up for it the day you raise. We track errors, releases, performance, and session replay all in one tool. When something breaks in production, Sentry tells you which deploy, which user, which browser, and which line within 30 seconds.

PostHog gives you product analytics, session replay, feature flags, experiments, and surveys on one free tier (1M events/month, 5K replays/month on the Cloud free plan as of early 2026). That combination used to cost you Mixpanel plus FullStory plus LaunchDarkly plus Typeform and $800/month minimum. Today it is $0 for your first year.

OpenTelemetry is the instrumentation standard we use regardless of where logs and metrics end up. Vendor-neutral, future-proof, and both Sentry and Datadog consume OTEL natively.

When we deviate#

• Security or compliance logs: ship to S3 with retention policy. Sentry and PostHog are not the audit log.
• Need APM at Series-B scale: Datadog. It is excellent. It is also $1K+/month the moment you have real traffic. Before that, Sentry's performance monitoring is enough.
• Self-host for data residency: Grafana + Prometheus + Loki. We have stood this up three times. Plan for one engineer half-time on it.

The Full MarsDevs 2026 MVP Stack, Summarized#

One more view. This is the reference table you screenshot and send to your cofounder when the agency pitch meeting starts. Every pick, one line, all 20 layers.

If you are about to build a SaaS product, start here. You can be shipping a logged-in, paying user in two weeks on this stack.

Stack Archetypes: B2B SaaS vs AI-First vs Marketplace vs Consumer Mobile#

The default stack holds across most archetypes. Four layers change depending on what you are building. The backend language choice, the database detail, the auth provider, and the AI layer scope.

Archetype 1: B2B SaaS (horizontal, multi-tenant)#

• Frontend: Next.js 15 (unchanged)
• Backend: Node 22 + Fastify 5 (unchanged)
• DB: Postgres 16, multi-tenant via organization_id column. RLS enforced at Supabase level or app layer.
• Auth: Clerk with Organizations enabled. Webhooks sync orgs to your tenants table.
• Payments: Stripe Billing with per-seat or metered pricing.
• AI: Often none at launch, or OpenAI for one or two smart features.
• Infra: Vercel + Railway.
• Watch-out: RLS on Supabase is powerful, easy to misconfigure. Review every policy before publishing.

Archetype 2: AI-first product#

• Frontend: Next.js 15 with Vercel AI SDK for streaming UI.
• Backend: FastAPI + Python 3.12 (different from default). You will want LlamaIndex, LangChain, vLLM, and HuggingFace tooling. All Python-native.
• DB: Postgres 16 + pgvector. One DB.
• Auth: Clerk.
• AI: OpenAI for structured outputs plus Anthropic Claude 4.5 for long context plus LangGraph for orchestration.
• Infra: Vercel (frontend) + Railway (FastAPI) + cloud LLM vendors. No self-hosted models until you have clear cost or compliance reasons.
• Watch-out: LLM costs are the scariest line item pre-revenue. Instrument token usage per endpoint from day one.

Archetype 3: Two-sided marketplace#

• Frontend: Next.js 15.
• Backend: Node 22 + Fastify 5, with a worker queue (BullMQ on Redis) for matching, notifications, and payouts.
• DB: Postgres 16. Schema maps supply, demand, transactions, ratings, disputes.
• Auth: Clerk with two roles (supplier / buyer) or Supabase Auth if you use Supabase end-to-end.
• Payments: Stripe Connect (this is where Connect earns its place). Payouts, account onboarding, and platform fees all handled.
• AI: Optional search relevance (embeddings plus pgvector) and fraud scoring.
• Infra: Vercel + Railway.
• Watch-out: Payout timing and dispute flows are the hardest UX, not the tech. Budget 40% of engineering time for trust and safety.

Archetype 4: Consumer mobile app#

• Frontend: React Native 0.77 + Expo 52 (different from default). Share ~60% of the code with a Next.js web app if you have one.
• Backend: Node 22 + Fastify 5 or FastAPI for the API.
• DB: Postgres 16.
• Auth: Clerk (first-class React Native support) or Supabase Auth.
• Payments: Stripe + RevenueCat for mobile-store subscription handling.
• AI: Optional.
• Infra: Vercel (marketing) + Railway (API). App Store + Play Store distribution. EAS Build for native artifacts.
• Watch-out: Apple's App Store rules change quarterly. Ship on Android first when you can.

The archetype decision matrix#

Four archetypes, one base stack, four surgical swaps. That is the point of picking defaults. Book a free strategy call if you want us to walk through your archetype in 30 minutes.

What an MVP on This Stack Costs#

Lean MVP on this stack runs $5,000 to $25,000. Standard MVP runs $8,000 to $30,000. AI MVP runs $5,000 to $30,000. Those are MarsDevs published ranges (VP-approved). Timeline is 3 to 12 weeks depending on scope and whether AI is in the critical path.

Our hourly rate is $15 to $25/hr for a senior team. Team composition on an MVP: one product manager, two full-stack engineers, one designer part-time, one QA part-time. Four projects per month cap. We do not take on a fifth even when the queue says yes, because quality erodes past four.

Infra cost in year one on this stack is $40 to $200/month depending on traffic. LLM API cost is the variable nobody can predict. We instrument every endpoint and set per-user quotas from day one. For the full breakdown see our cost to build a SaaS application in 2026 piece.

Lived Experience: One Project We Shipped on This Exact Stack#

Here is one anonymized example so this stack is not hypothetical.

A B2B HR-tech startup came to us in Q1 2025. They had 6 weeks of runway, a contract with a design partner, and needed a working product or the contract disappeared. We scoped it aggressively. Single-tenant, Clerk for auth, Stripe for billing, Supabase for everything (Postgres, auth metadata, storage for uploaded CSVs), Next.js 15 on Vercel, one AI feature (resume parsing with OpenAI GPT-4o and Claude Sonnet 3.7 as a fallback, which were the current models then).

We shipped the MVP in 5 weeks and 3 days. Infra cost for the first 90 days was $142 total across Vercel, Supabase, and OpenAI API calls. The design partner signed the annual contract in week 8. The founder closed a $600K angel round the month after on the strength of that one logo. That is what the stack is for. Ship the product before the runway ends.

Quotable: We shipped a B2B HR-tech MVP in 5 weeks and 3 days on Next.js 15 + Supabase + Clerk + Stripe + OpenAI. First-90-day infra cost was $142. The design partner signed the annual contract in week 8.

We have run this play dozens of times since 2019 on variants of this stack. The stack is not the magic. Picking it once and defending it is.

When to NOT Use Our Defaults (and What We'd Pick for 2027)#

This stack is wrong for you in four situations. Know them before you copy-paste our picks.

1. You are building a game, CAD tool, or real-time graphics product#

Next.js plus Postgres is not the stack. You want Unity, Unreal, or a WebGPU-first framework (Three.js, Babylon). Our defaults assume CRUD plus some AI plus some transactions.

2. You are Series B+ with compliance that dictates AWS or GCP#

If HIPAA, FedRAMP, or a bank customer demands VPC peering and no third-party auth vendor, Vercel and Clerk are harder conversations. You end up on AWS ECS + RDS + Cognito or Okta. That stack ships slower and costs more. Worth it when the customer is paying for it.

3. Your team is deeply Ruby, .NET, or Java already#

Do not force a rewrite because an article said so. Rails 8 ships real products every week. .NET 9 is a solid, fast web stack. A Java team using Spring Boot will outship a Node team that does not know Node. The stack matters less than the team's fluency.

4. You need sub-10ms p99 latency at global scale#

Vercel and Railway are fine to 50ms p99 in most regions. Below that, Cloudflare Workers + Durable Objects or Fly.io + regional Postgres replicas become the conversation. We have shipped one project at that constraint and it doubled our DevOps time.

What we think we will change by 2027#

Three picks are on our watchlist. We will not pre-commit, but if you are reading this in late 2026 and things have moved:

• Auth: Better Auth is improving fast. If it ships SSO on par with Clerk and beats it on price, it becomes our default for self-hostable auth.
• Vector store: pgvector is great today. If Turbopuffer or a Postgres-native serverless vector offering beats it on cost at 10M+ vectors, we will adopt.
• Orchestration: LangGraph is winning among options today. The MCP ecosystem might shift this. We will see.
• Backend for AI: If a TS-native ecosystem for ML libraries reaches parity with Python's (it has not), we may unify on Node. We are not holding our breath.

Next.js, Postgres, Stripe, Vercel, Resend, and Sentry are not going anywhere.

Frequently Asked Questions#

What is the best tech stack for a startup in 2026?#

The MarsDevs 2026 default: Next.js 15 (App Router) + Fastify 5 or FastAPI + Postgres 16 (on Supabase) + Drizzle ORM + Clerk + Stripe + Vercel + Railway + OpenAI and Anthropic APIs + PostHog + Sentry + Resend. One pick per layer. We ship new MVPs on this every week.

Should my startup use Next.js or Remix in 2026?#

Next.js. The App Router with React Server Components is stable, the Vercel deploy path is zero-config, and the hiring pool is roughly 5x deeper than Remix. Remix (now part of React Router v7) is a fine framework. Next.js is the shorter path to production.

Is Supabase production-ready for a SaaS in 2026?#

Yes, for MVP through early Series A. We have shipped on Supabase and migrated two projects off it post-Series A to self-hosted Postgres when workload patterns demanded custom tuning. Supabase is Postgres, so migration is a data move, not a rewrite.

Which is cheaper to deploy on: Vercel, Railway, Fly.io, or Render?#

Per-compute, Fly.io is usually cheapest. Railway has the best DX and Postgres co-located. Vercel is the fastest path for Next.js. Our default is Vercel + Railway at $40 to $60/month for most MVP workloads.

Do I need LangChain for my AI startup in 2026, or can I just call OpenAI directly?#

Call the API directly for under three chained prompts. Reach for LangGraph (the stateful layer on top of LangChain) once you have tool use, memory across turns, or multi-agent flows. Most AI MVPs start with direct API calls and graduate later.

What does it cost to build an MVP on this stack?#

Lean MVP runs $5,000 to $25,000. Standard MVP runs $8,000 to $30,000. AI MVP runs $5,000 to $30,000. Timelines: 3 to 8 weeks for a mobile app, 3 to 12 weeks for an AI MVP, 2 to 10 weeks for an AI agent. MarsDevs hourly rate is $15 to $25/hr for a senior team.

Should I pick MongoDB or Postgres for my startup?#

Postgres by default. MongoDB only when the schema is genuinely unknown at design time, which is rare. Postgres 16 handles relational data, JSONB for schemaless fields, full-text search, pgvector for embeddings, and realtime. One database covers most needs through Series A.

Is pgvector good enough, or do I need Pinecone?#

pgvector is good enough until roughly 10 million vectors or sub-50ms p99 retrieval on huge catalogs. Below that, pgvector inside your existing Postgres saves you an entire database to operate. Above it, benchmark Pinecone, Weaviate, or Qdrant against your specific recall targets.

What auth provider is best for a Next.js startup?#

Clerk. Best Next.js DX, free to 10,000 MAU, roughly $0.02 per MAU after, about 3x cheaper than Auth0 at equivalent tiers. Supabase Auth is the alternative when you are using Supabase end-to-end for the rest of the stack.

Do I need Datadog as a startup?#

No. Sentry (free Developer plan, $50K startup credits available) plus PostHog (1M free events/month) cover error tracking, performance, session replay, product analytics, and feature flags through Series B. Datadog becomes worth $1K+/month once you have scale that justifies it.

Ship on the Stack We Defend#

If you are evaluating an agency pitch, ask them which layer they last replaced and why. If they cannot answer, they are guessing. We replaced Prisma with Drizzle in late 2025 after three production issues in two months. We moved our default AI orchestration from plain LangChain to LangGraph when state management became the bottleneck. Those are real answers.

If you want to ship an MVP on this stack, we take on 4 new projects per month. Book a free strategy call and we will walk through your archetype, scope, and a committed 3 to 12 week timeline before you write a check. Start building in 48 hours.

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MarsDevs is a product engineering company that builds AI-powered applications, SaaS platforms, and MVPs for startup founders. Founded in 2019, we have shipped 80+ products across 12 countries. 4.9 rating on Clutch.

Related reading:

• How to build an MVP
• Build a SaaS product
• AI MVP in 2026
• Cost to build a SaaS application in 2026