Best Tech Stack to Build a SaaS in 2026: The Opinionated Guide

PostgreSQL just became the #1 database, used by 55.6% of professional developers (Stack Overflow Developer Survey 2025, 2025). TypeScript overtook both Python and JavaScript on GitHub, reaching 2.63 million monthly contributors (Java Code Geeks, 2026). And 84% of developers now use AI coding tools (index.dev, 2026) — though a METR study found experienced devs are actually 19% slower with them. Something doesn't add up.

Meanwhile, 65% of founders spend less than $50/month on infrastructure during the MVP phase (wearefounders.uk, 2026). The tools are free or nearly free. The ecosystem is mature. The excuses are gone.

This guide isn't a "10 options for every layer" comparison. It's one stack, one recommendation, backed by data and first-hand experience building on it. The "best" tech stack in 2026 isn't about what's trending on Hacker News — it's about what lets a solo founder or small team ship fast, stay cheap, and scale without rewriting everything at $10K MRR. If you already know what to build, keep reading. If you don't, start with our 20 micro-SaaS ideas for 2026 and come back here when you're ready.

TL;DR: The recommended 2026 SaaS stack is TypeScript + Next.js + Tailwind + Supabase + Vercel + Stripe + Resend. PostgreSQL is the #1 database (55.6% adoption), React the #1 framework (44.7%), and TypeScript the #1 language on GitHub (2.63M contributors) (Stack Overflow 2025, 2025). You can run the entire stack for $0/month at MVP and under $200/month at $1K MRR. AI coding tools are standard now — but use them wisely.

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The 2026 SaaS Stack at a Glance

The entire stack recommended in this guide uses 7 tools, all with free tiers, covering every layer a SaaS needs from database to payments. React dominates the frontend at 44.7% developer adoption (Stack Overflow 2025, 2025), PostgreSQL dominates the database layer at 55.6%, and TypeScript dominates GitHub with 2.63M monthly contributors (Java Code Geeks, 2026). Every piece of this stack was chosen because it's the most popular, best-documented, and most cost-effective option in its category.

Here's what we're building with:

Why this specific combination? Three reasons. First, everything is TypeScript end-to-end — your frontend, backend, API routes, database types, and email templates all share the same language. Second, every tool has a free tier generous enough to get you to first revenue. Third, this stack has the largest community, which means the most tutorials, the most Stack Overflow answers, and the best AI code generation quality (models are trained on what's popular).

Citation capsule: The recommended 2026 SaaS stack spans 7 tools all with free tiers: TypeScript, Next.js + React (44.7% adoption), Tailwind CSS (51% adoption), PostgreSQL via Supabase (55.6% — the #1 database), Vercel, Stripe ($1.9T volume), and Resend (Stack Overflow 2025, 2025).

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Why Is TypeScript the Only Serious Choice?

TypeScript is used by 43.6% of professional developers (Stack Overflow Developer Survey 2025, 2025) and reached 2.63 million monthly contributors on GitHub in 2025, overtaking both Python and JavaScript for the first time (Java Code Geeks, 2026). Among JavaScript developers specifically, 40% now write exclusively in TypeScript, up from 34% the year before (InfoQ / State of JS 2025, 2026).

The shift isn't surprising if you've shipped production code in both languages. TypeScript catches entire categories of bugs at compile time that JavaScript lets slip to production. Undefined is not a function? Type errors in API responses? Wrong prop types crashing a component? Gone.

But the real advantage for SaaS builders is full-stack type sharing. When your Next.js frontend, your API routes, your Supabase database types, and your Zod validation schemas all share a single type system, refactoring stops being scary. Change a database column, and TypeScript tells you every file that needs updating. That feedback loop is worth more than any framework feature.

There's another angle people miss. AI coding tools generate significantly better TypeScript than JavaScript. Why? Because type annotations give the model more context about your intent. When Cursor or Copilot sees a typed function signature, it can infer what the body should do with higher accuracy. Types are documentation that both humans and AI can read.

TypeScript isn't just a preference — it's a multiplier. When your frontend, backend, API routes, and database types all share a single source of truth, you eliminate an entire class of bugs. For a solo founder shipping fast, that's the difference between deploying with confidence and deploying with crossed fingers.

Is there any serious argument for plain JavaScript in 2026? Not really. The initial setup cost of TypeScript is negligible with modern tooling. Next.js scaffolds a TypeScript project by default. The "learning curve" argument made sense in 2020. In 2026, not knowing TypeScript is the liability.

Citation capsule: TypeScript is used by 43.6% of professional developers and reached 2.63 million monthly contributors on GitHub, overtaking Python and JavaScript as the most active language (Java Code Geeks, 2026). With 40% of JS developers writing exclusively in TypeScript, it's now the default for any new SaaS project.

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Why Next.js + React + Tailwind for the Frontend?

React is used by 44.7% of professional developers, making it the most popular web framework by a wide margin (Stack Overflow 2025, 2025). Next.js, the leading React meta-framework, sits at 20.8% adoption and powers 2.4% of all websites worldwide (W3Techs, 2026). Tailwind CSS has hit 51% adoption among developers, with 31.1 million weekly npm downloads — that's 12.5x Bootstrap's numbers (BuiltWith, 2026).

Why React Over Everything Else?

The honest answer: ecosystem size. React has more component libraries, more tutorials, more open-source projects, and more developers than any alternative. When you hit a weird edge case at 2 AM, someone on the internet has already solved it in React. That matters more than any benchmark.

React Server Components (RSC) in Next.js changed the game for SaaS. Your marketing pages, documentation, and dashboards can render on the server — shipping zero JavaScript to the client for static content. Interactive components like editors and forms still run client-side. You get the SEO benefits of server rendering and the UX benefits of a single-page app. No compromise required.

Why Next.js Specifically?

Next.js gives you routing, server-side rendering, API routes, middleware, and image optimization out of the box. The App Router with React Server Components means less client-side JavaScript by default. That translates to faster page loads and better Core Web Vitals — both of which matter for SEO and user retention.

Node.js (the runtime underneath) is used by 48.7% of developers (Stack Overflow 2025, 2025). Your backend and frontend run the same language, same runtime, same package manager. One mental model for everything.

What About the Alternatives?

Remix has great developer experience and strong data loading patterns. But its ecosystem is smaller, and hosting options are less optimized compared to Next.js on Vercel. If you're already comfortable with Remix, it's fine. But for a new project, Next.js gives you more out of the box.

SvelteKit is genuinely loved by developers who use it. The syntax is cleaner, the bundle sizes are smaller. But React's ecosystem is roughly 10x larger. When you need a date picker, a rich text editor, a charting library, or an auth component — React has ten options. Svelte might have one or two.

Vue/Nuxt is solid technology with a loyal community. But the job market is smaller, component library selection is narrower, and AI tools generate worse Vue code because there's less training data.

Why Tailwind CSS?

Tailwind killed the "should I use CSS modules or styled-components?" debate. Utility classes directly in your JSX mean no context-switching between files, no naming conventions to argue about, and no dead CSS accumulating over time. At 31.1M weekly downloads, it has critical mass. Every component library worth using supports it.

We built StartuPage on Next.js + React + Tailwind. The combination of server components for SEO-critical pages and client components for interactive editors gives us the best of both worlds — fast initial loads and rich interactivity where it matters.

Citation capsule: React leads frontend frameworks at 44.7% developer adoption, with Next.js at 20.8% and Tailwind CSS at 51% adoption with 31.1 million weekly npm downloads, 12.5x Bootstrap's install rate (Stack Overflow 2025, 2025; BuiltWith, 2026).

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Why PostgreSQL + Supabase for the Database?

PostgreSQL is the #1 database among professional developers at 55.6% adoption, followed by MySQL at 40.5% and MongoDB at 24.8% (Stack Overflow 2025, 2025). Supabase — the open-source Firebase alternative built on PostgreSQL — reached $70M ARR with 250% year-over-year growth and over 4 million developers (Sacra Research, 2025). Its valuation climbed to roughly $5B, up from $765M (Sacra, 2025).

Why PostgreSQL Over MySQL or MongoDB?

PostgreSQL won the database war. It's not even close anymore. PostgreSQL handles relational data, JSON data, full-text search, vector embeddings (for AI features), and geospatial queries — all in one database. MySQL can't touch that feature set. MongoDB forces you into document-based modeling that creates headaches the moment your SaaS has complex relationships between users, teams, subscriptions, and resources.

For SaaS specifically, relational data modeling is almost always the right choice. Users belong to organizations. Organizations have subscriptions. Subscriptions have invoices. These are relationships. PostgreSQL was literally built for this.

Why Supabase Over Raw PostgreSQL?

You could host PostgreSQL yourself on AWS RDS or DigitalOcean. But then you're managing backups, connection pooling, auth, storage, and realtime subscriptions separately. Supabase bundles all of that into one platform with a generous free tier: 500MB database, 50K monthly active users for auth, 1GB file storage, and 500MB bandwidth.

The serverless PostgreSQL market is projected to reach $1.71B-$2.19B by 2026 with a 28.1% CAGR (Research and Markets, 2026). Supabase is riding this wave harder than anyone.

Why Not Firebase?

Firebase uses Firestore (NoSQL), which means no joins, no foreign keys, and no relational integrity. For a simple app, that's fine. For a SaaS with multi-tenancy, role-based access, and complex billing relationships, it becomes a nightmare. Firebase is also used by only 13.1% of developers (Stack Overflow 2025, 2025) and locks you into Google's ecosystem. Supabase is open-source — if you ever need to leave, you can export your PostgreSQL database and host it anywhere.

Why Not PlanetScale or Neon?

PlanetScale killed its free tier, which eliminated it from the MVP conversation. It also runs MySQL, not PostgreSQL. Neon is excellent serverless PostgreSQL, but it gives you just the database. Supabase gives you the database plus auth, realtime, storage, edge functions, and a dashboard — all integrated. For a solo founder or small team, fewer vendors means fewer things to manage.

The Killer Feature: Row Level Security

Row Level Security (RLS) is PostgreSQL's built-in mechanism for multi-tenancy. You write policies at the database level that enforce "users can only see their own data." This means even if your API has a bug that exposes the wrong data, the database itself blocks unauthorized access. For SaaS, this is a massive security advantage that no NoSQL database offers natively.

Citation capsule: PostgreSQL dominates at 55.6% developer adoption as the #1 database, while Supabase — the open-source Firebase alternative built on PostgreSQL — reached $70M ARR growing 250% YoY with 4M+ developers (Stack Overflow 2025, 2025; Sacra, 2025).

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What About Authentication? Use Supabase Auth

Since Supabase is already your database, using its built-in auth is the obvious choice. Zero additional vendors, zero additional cost, and deep integration with Row Level Security policies. OAuth providers like Google, GitHub, and LinkedIn are configured directly in the Supabase dashboard — no code changes needed to add a new provider.

Session management works through @supabase/ssr, which handles cookies in Next.js server components and API routes. Your auth state is available everywhere: server components, client components, middleware, and API routes. And because auth is tied to RLS, your database policies can reference the authenticated user directly. "Select rows where user_id = auth.uid()" is a one-line policy that enforces data isolation across your entire application.

How Do Alternatives Compare?

Clerk has better pre-built UI components (sign-in modals, user profiles, organization management). If design polish is a priority and you don't mind adding another vendor, Clerk is worth considering. But it starts at $25/month after the free tier, and it doesn't integrate with your database's access control layer.

Auth0 is enterprise-grade authentication with every feature you could want. It's also overkill for an early-stage SaaS and gets expensive fast. The free tier is limited to 25,000 monthly active users, which sounds generous until you realize the paid plans start at $240/year.

NextAuth (Auth.js) is free and open-source. The trade-off is DIY session management, no built-in user management dashboard, and no integration with database-level security policies. It works, but you're assembling pieces that Supabase gives you as a complete system.

The right call for most founders: start with Supabase Auth. If you outgrow it or need enterprise features, migrate to Clerk or Auth0 later. But don't add complexity before you need it.

Citation capsule: Supabase Auth provides built-in authentication with OAuth providers, session management via @supabase/ssr, and deep integration with PostgreSQL Row Level Security — all at zero additional cost when using Supabase as your database, eliminating the need for separate auth vendors like Clerk ($25+/mo) or Auth0.

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Why Vercel for Hosting?

Vercel is used by 10.6% of professional developers (Stack Overflow 2025, 2025) and was literally built by the same company that created Next.js. That relationship matters. Every Next.js feature — server components, middleware, ISR, image optimization, edge functions — works perfectly on Vercel with zero configuration. Deploy by pushing to git. That's it.

Preview deployments are an underrated feature. Every pull request gets its own URL, so you (or your team, or your beta testers) can review changes before they hit production. Analytics are built into the dashboard. Edge functions run your middleware globally, close to your users.

The Pricing Reality

Here's the part most "best stack" articles skip. Vercel's free tier is hobby-only — you can't use it for commercial projects. The Pro plan costs $20 per seat per month (TheSoftwareScout, 2026). A team of three is $60/month before you serve a single user.

At scale, bandwidth and serverless function invocation costs can surprise you. We've seen stories of $500+ bills from traffic spikes. Monitor your usage carefully and set spending limits.

That said, $20/month for a solo founder is reasonable. You're getting world-class infrastructure, automatic HTTPS, global CDN, and zero DevOps overhead. The time you save is worth far more than $20.

What Are the Alternatives?

Cloudflare Pages is cheaper at scale and has an incredible edge network. Cloudflare is used by 20.1% of developers (Stack Overflow 2025, 2025) — nearly double Vercel. But Next.js support on Cloudflare is still catching up. Some features (like certain RSC patterns) may not work perfectly. If you're building a more static site or using a different framework, Cloudflare is hard to beat on price.

Railway is great for backend services and has transparent, usage-based pricing. It's less optimized for Next.js specifically but works well if you're deploying a Node.js server or need background workers alongside your frontend.

Fly.io excels at global deployment with containers running close to users. But it requires more DevOps knowledge — Dockerfiles, health checks, scaling configuration. If you want zero-config deploys, Vercel is the answer.

Citation capsule: Vercel, used by 10.6% of developers, is built by the creators of Next.js and offers zero-config deployments with preview URLs, edge functions, and built-in analytics, though its Pro tier costs $20/seat/month and bandwidth costs can spike at scale (Stack Overflow 2025, 2025; TheSoftwareScout, 2026).

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Why Stripe for Payments?

Stripe processed $1.9 trillion in payment volume in 2025, controlling 68% of the US eCommerce payment market (Backlinko, 2025). Revenue hit $19.4 billion — up 17% year-over-year — with a valuation of $159 billion (Capital One Shopping, 2026). When two-thirds of US eCommerce runs through one platform, the "which payment processor?" question answers itself.

The developer experience is what sets Stripe apart. The documentation is the best in fintech. The API is consistent and well-designed. Stripe Billing handles subscriptions with proration, trials, coupons, and dunning (failed payment recovery) out of the box. Stripe Connect lets you build marketplace payments. The Billing Portal gives your customers a self-service page to manage their subscription without you building anything.

The Lemon Squeezy Acquisition Changes Everything

In 2025, Stripe acquired Lemon Squeezy and launched Stripe Managed Payments — a Merchant of Record (MoR) service (Lemon Squeezy Blog, 2025). This is significant. Previously, if you wanted someone else to handle global sales tax collection and remittance, you had to use Paddle or Lemon Squeezy instead of Stripe. Now Stripe offers that natively.

For SaaS selling globally, the MoR model means you don't have to register for VAT in the EU, collect GST in Australia, or figure out sales tax in 12,000+ US tax jurisdictions. Stripe handles it. This removes the biggest reason founders used to choose alternatives over Stripe.

What about subscription vs. usage-based pricing? That's a product decision, not a tech decision. Stripe supports both models well. For a deeper breakdown of which pricing model fits your SaaS, check out our guide to SaaS pricing models.

Is There a Real Alternative?

Paddle is the main competitor. It's been a native Merchant of Record from the start, meaning it has more experience with global tax compliance. If you're selling exclusively to consumers in complex tax jurisdictions and don't need Stripe Connect or marketplace features, Paddle is worth evaluating. But with Stripe now offering MoR via the Lemon Squeezy acquisition, Paddle's moat is shrinking.

Citation capsule: Stripe processed $1.9 trillion in payment volume in 2025, commands 68% of US eCommerce, and now offers Merchant of Record capabilities through its Lemon Squeezy acquisition, handling global sales tax collection so SaaS founders don't have to register for VAT or GST individually (Backlinko, 2025; Lemon Squeezy, 2025).

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Why Resend for Email?

SendGrid retired its permanent free plan in May 2025, pushing thousands of indie developers to find alternatives (Dreamlit, 2025). Resend stepped into the gap with 3,000 emails per month free (Dreamlit, 2025) and a developer experience built for the modern stack. For transactional email in 2026, it's the clear winner for small teams.

What makes Resend different from every other email API? React Email. You build your email templates using JSX — the same syntax as your Next.js components. No more fighting with HTML table layouts from 2005. No more switching between your app's component model and some templating language. Your email templates live in your codebase, use your TypeScript types, and render with React. It's the same mental model as the rest of your stack.

For a SaaS MVP, you need transactional email: password resets, welcome emails, payment receipts, usage notifications. Resend's 3,000/month free tier covers all of that until you have serious traction.

What If You Need More?

Postmark has excellent deliverability and transparent pricing. It's a solid choice if email delivery speed is critical to your product (think: two-factor auth codes).

Amazon SES is the cheapest option at scale — $0.10 per 1,000 emails. But the setup is more complex, and you're responsible for managing bounce handling, suppression lists, and reputation monitoring yourself.

Loops is interesting if you need both transactional and marketing email in one platform. It combines product notifications with drip campaigns and newsletters, which eliminates the need for a separate tool like Mailchimp or ConvertKit.

Citation capsule: After SendGrid retired its permanent free plan in 2025, Resend emerged as the top transactional email choice for SaaS developers, offering 3,000 emails/month free and React Email for building templates in JSX — the same language as the rest of the recommended stack (Dreamlit, 2025).

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How Are AI Coding Tools Changing the Stack?

84% of developers use or plan to use AI coding tools (index.dev, 2026), and 41% of all code written in 2025 was AI-generated (index.dev, 2026). This isn't a niche trend anymore. AI is a standard layer of the development stack, whether you're a solo founder or a team of fifty.

GitHub Copilot has over 1.8 million paid subscribers and is used by 90% of Fortune 100 companies (index.dev, 2026). Cursor crossed $500M ARR and is used by half of the Fortune 500 (index.dev, 2025). The market has spoken: AI-assisted coding is the default workflow.

The Uncomfortable Truth About AI Productivity

Here's where it gets interesting — and where most articles get it wrong. A rigorous study by METR found that experienced open-source developers were actually 19% slower when using AI tools on real-world tasks (n=16 developers, 246 issues) (METR.org, 2025). The kicker? Those same developers perceived a 20% speedup despite the actual slowdown (METR.org, 2025).

How is that possible? The study suggests AI tools feel productive because they reduce the effort of typing and thinking about syntax. But they introduce a new cost: reviewing AI-generated code, debugging subtle errors, and managing context when the AI goes off-track. For complex, familiar codebases, that overhead outweighs the speed gains.

The METR study is the most important data point nobody talks about. Experienced developers were actually 19% slower with AI assistance — while believing they were 20% faster. AI tools are genuinely useful for boilerplate, documentation, and exploring unfamiliar codebases. But for complex architecture decisions and debugging, they can actively slow you down by generating plausible-looking code that's subtly wrong. Use AI as an accelerator for the boring stuff, not a replacement for thinking.

Which AI Tools Should You Actually Use?

Cursor + Claude is the best combination for agentic coding. Cursor understands your full project context — it reads your files, your types, your imports — and Claude's reasoning capabilities make it strong at multi-file refactoring, complex logic, and architectural decisions. Use it for generating boilerplate, writing tests, and exploring unfamiliar APIs.

GitHub Copilot remains the best for inline autocomplete. It's fast, unobtrusive, and handles single-line completions well. Many developers use both: Copilot for moment-to-moment autocomplete and Cursor for larger tasks.

Claude Code (CLI) is excellent for terminal-based development, automation scripts, and working with codebases too large for an IDE context window.

Where AI Helps vs. Where It Hurts

Use AI for: boilerplate generation, test writing, documentation, data transformation, exploring unfamiliar libraries, and CSS styling. These are tasks where speed matters more than depth.

Don't rely on AI for: architecture decisions, security-critical code, complex state management, database schema design, or performance optimization. These require understanding your specific business context in ways current AI tools can't replicate.

Citation capsule: While 84% of developers use AI coding tools and 41% of code is AI-generated, a METR study found experienced developers are actually 19% slower with AI assistance on complex tasks — despite perceiving a 20% speedup — suggesting AI is best used for boilerplate and exploration rather than core architecture (METR.org, 2025; index.dev, 2026).

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What Does This Entire Stack Cost?

65% of founders spend less than $50/month on their tech stack during the MVP phase, and the average bootstrapped MVP costs $2,800 to launch (wearefounders.uk, 2026). With the stack recommended in this guide, you can hit $0/month at launch and stay under $200/month well past your first $1K in revenue.

Here's the breakdown by stage:

The math works. At $1K MRR, your infrastructure costs are 10-20% of revenue. At $10K MRR, they drop to 3-5%. That's a healthy margin for a bootstrapped SaaS, and you haven't had to re-architect anything.

What's missing from this table? Your domain ($12/year), analytics (Plausible at $9/month or Vercel Analytics included in Pro), error monitoring (Sentry has a free tier), and your time. Your time is the real cost — and that's exactly why this stack prioritizes developer experience over raw performance benchmarks.

For a full breakdown of how to manage your startup's finances at each stage, including when to hire and how to calculate runway, check our burn rate guide.

At StartuPage we ran on free tiers for the first three months. Supabase's free tier (500MB database, 50K auth users, 1GB storage) and Vercel's hobby plan were enough to validate the product and get our first paying users. The entire infrastructure cost us $0 until we had revenue to cover it.

Citation capsule: The recommended SaaS stack costs $0/month at MVP and under $200/month at $1K MRR, consistent with the finding that 65% of founders spend less than $50/month on infrastructure during the MVP phase and the average bootstrapped SaaS costs $2,800 to launch (wearefounders.uk, 2026).

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Frequently Asked Questions

Is Next.js still the best framework for SaaS in 2026?

Yes. With 20.8% developer adoption and React's 44.7% market share behind it, Next.js has the largest ecosystem, best hosting support (Vercel), and the most comprehensive feature set of any React framework (Stack Overflow 2025, 2025). The App Router with React Server Components gives you SSR performance without sacrificing interactivity. Unless you have a strong reason to choose something else, Next.js is the default.

Should I use Supabase or Firebase for my SaaS?

Supabase. Firebase uses NoSQL (Firestore), which creates data modeling headaches for SaaS products with complex relationships. Supabase gives you PostgreSQL — the #1 database at 55.6% adoption (Stack Overflow 2025, 2025) — Row Level Security for multi-tenancy, built-in auth, and no vendor lock-in. You can always export your PostgreSQL database and migrate to any other host.

How much does it cost to build and run a SaaS in 2026?

$0/month at MVP using free tiers from Vercel, Supabase, Resend, and Stripe (pay-per-transaction only). Under $50/month for the first 100 users. Under $200/month at $1K MRR. 65% of founders spend less than $50/month during the MVP phase (wearefounders.uk, 2026). The average bootstrapped MVP costs $2,800 total to launch.

Do I need Docker for a SaaS in 2026?

Not if you're using Vercel + Supabase. Docker is used by 71.1% of developers overall, but serverless platforms like Vercel abstract away container management entirely. You'll only need Docker if you're self-hosting, deploying to AWS/GCP directly, or using Railway/Fly.io for custom backend services. For the recommended stack in this guide, skip Docker and save yourself the DevOps overhead.

Is AI replacing developers in 2026?

No. While 41% of code is AI-generated (index.dev, 2026), the METR study showed experienced developers are actually 19% slower with AI on complex tasks (METR.org, 2025). AI is a productivity tool for boilerplate, tests, and exploration — not a replacement for engineering judgment. The best founders use AI to ship faster on repetitive tasks and think harder on the important architectural decisions.

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The Bottom Line

The best tech stack is the one that lets you ship. In 2026, that stack is TypeScript + Next.js + Tailwind + Supabase + Vercel + Stripe + Resend. It's battle-tested by millions of developers. It costs $0 to start. And it scales to $10K+ MRR without a rewrite.

Every tool in this stack was chosen for the same reason: it's the most popular, best-documented, and most cost-effective option in its category. That might sound boring. Good. Boring technology is what lets you focus on your product instead of your infrastructure.

Now that you have the stack, you need the idea. Check out our 20 micro-SaaS ideas for 2026 — each one selected for AI-proof defensibility. And when you're ready to launch, create a free startup profile on StartuPage to get verified metrics and visibility from day one.

One more thing. Building with a clean, maintainable stack isn't just about developer happiness — it directly affects your exit valuation. Buyers pay premium multiples for SaaS built on modern, well-documented infrastructure. The stack you choose today is the stack a buyer evaluates tomorrow.