Build vs. Buy in the AI Era: Which Dev Tools Can You Replace?

The calculus of "build vs. buy" has fundamentally shifted. With AI coding assistants like Claude, Cursor, and GitHub Copilot, a solo developer can now build in days what previously took teams weeks. But that does not mean you should build everything.

This guide breaks down which categories of developer tools are now realistic to build yourself, which remain solidly in "just buy it" territory, and how to think about the decision.

TL;DR

The new build vs. buy framework

Before AI assistants, the framework was simple: "How long will this take to build vs. how much does the tool cost?"

Now you need to add: "How long will this take to build with AI assistance?"

But time is only one factor. The real framework has three dimensions:

1. Initial build complexity

How hard is it to get a working v1? AI dramatically reduces this for most tools.

2. Maintenance burden

Who fixes bugs, handles edge cases, and updates dependencies? AI helps less here.

3. Liability and compliance

Are there security, legal, or regulatory implications? AI cannot help with these.

Category breakdown

Analytics: Build it

Difficulty with AI: Easy (1-2 days)

Basic analytics is now trivial to build:

• •Event tracking: A few API endpoints storing events in your database
• •Dashboards: AI can generate chart components quickly
• •Session tracking: Cookie + database, nothing complex

What makes buying still worthwhile:

• •Privacy compliance (GDPR, cookie consent)
• •Real-time dashboards at scale
• •Funnel analysis and cohort reports
• •Integration with ad platforms

Verdict: Build if you need simple pageviews and events. Buy (Plausible, PostHog) if you need product analytics, session replay, or compliance.

Email sending: Build the basics, buy deliverability

Difficulty with AI: Easy to send, hard to deliver

Sending email is trivial:

• •Use nodemailer or any SMTP library
• •Connect to AWS SES, Mailgun, or even Gmail SMTP
• •Template with React Email or plain HTML

What you cannot build:

• •Deliverability reputation (takes months/years)
• •Inbox placement optimization
• •Bounce handling at scale
• •Compliance with email regulations

Verdict: Build the sending logic and templates. Buy the infrastructure (Resend, Postmark, SendGrid) for deliverability.

CMS: Build for simple cases

Difficulty with AI: Moderate (3-7 days)

A basic CMS is very buildable:

• •Content models in your database
• •Admin UI with forms (AI generates these quickly)
• •API endpoints for fetching content
• •Markdown or rich text editing

What makes buying worthwhile:

• •Visual editing for non-technical users
• •Media management and optimization
• •Localization and versioning
• •Real-time collaboration

Verdict: Build if developers manage content. Buy (Sanity, Contentful) if non-technical users need to edit content regularly.

Monitoring and logging: Hybrid approach

Difficulty with AI: Moderate (2-5 days for basics)

Basic monitoring is achievable:

• •Structured logging to your database
• •Error tracking with stack traces
• •Simple alerting via Slack/email
• •Basic health check dashboards

What requires buying:

• •Log aggregation at scale
• •APM and distributed tracing
• •Anomaly detection
• •Incident management workflows

Verdict: Build basic error logging and health checks. Buy (Sentry, BetterStack) for production error tracking with context.

Authentication: Think twice before building

Difficulty with AI: Hard (2-4 weeks for basics, months for enterprise)

Auth seems simple until you list the requirements:

• •Password hashing and storage
• •Session management
• •OAuth integration (each provider is different)
• •Magic links and passwordless
• •MFA/2FA
• •Password reset flows
• •Account lockout and rate limiting
• •Session revocation
• •SAML/SSO for enterprise

The real costs of building:

• •Security vulnerabilities you have not thought of
• •Ongoing maintenance as OAuth providers change
• •Compliance requirements (SOC2, HIPAA)
• •Support burden when users cannot log in

What AI helps with:

• •Generating boilerplate auth code
• •Implementing standard flows
• •Writing tests for auth logic

What AI cannot help with:

• •Security review and penetration testing
• •Compliance certification
• •The 3 AM incident when auth breaks

Verdict: Buy (Clerk, Auth0, Supabase Auth) unless you have specific requirements they cannot meet or a dedicated security team.

Payments: Almost always buy

Difficulty with AI: Very Hard (months for basics, years for enterprise)

Payments is the clearest "buy" category:

What you would need to build:

• •PCI compliance (expensive annual audits)
• •Fraud detection and prevention
• •Chargeback handling
• •Tax calculation and remittance
• •Subscription lifecycle management
• •Payment method storage
• •Multi-currency support
• •Regulatory compliance per country

The liability:

• •PCI non-compliance fines: up to $100K/month
• •Fraud losses come from your revenue
• •Tax errors create legal liability
• •Chargebacks can freeze your accounts

Verdict: Always buy (Stripe, Paddle, LemonSqueezy). The liability alone makes building impossible for most companies.

Hosting and infrastructure: Never build

Difficulty with AI: Very Hard (this is an entire business)

"Building your own hosting" means:

• •Provisioning and managing servers
• •Networking, load balancing, DDoS protection
• •SSL certificates and DNS
• •CI/CD pipelines
• •Monitoring and alerting
• •Disaster recovery
• •24/7 on-call support

AI can help you write deployment scripts. AI cannot run your infrastructure at 3 AM when things break.

Verdict: Always buy (Vercel, Railway, Render). Hosting is their core business, not yours.

Decision framework

Ask these questions in order:

1. Is there liability or compliance involved?

If yes (payments, auth for sensitive data, healthcare, finance), buy.

2. Is this your core product differentiator?

If no, strongly consider buying. Spend your AI-assisted development time on what makes your product unique.

3. How much ongoing maintenance will this require?

• •One-time build: Consider building
• •Ongoing updates and edge cases: Consider buying

4. What happens when it breaks at 3 AM?

If the answer is "our users cannot use the product," strongly consider buying from a vendor with 24/7 support.

5. Does a good solution cost less than a week of your time?

At $100-200/hour for developer time, a $50/month tool pays for itself quickly.

The hybrid approach

The best answer is often hybrid:

• •Build the integration layer and custom logic
• •Buy the core infrastructure
• •Use AI to build everything around it faster

Example: Auth

• •Buy Clerk or Auth0 for the auth infrastructure
• •Build custom onboarding flows with AI assistance
• •Build role-based UI logic with AI assistance
• •Let the vendor handle the security-critical parts

Example: Email

• •Buy Resend or Postmark for deliverability
• •Build email templates with React Email + AI
• •Build sending logic and queues yourself
• •Let the vendor handle inbox placement

Tools most likely to be displaced by AI

Based on our analysis, these tool categories are most vulnerable to "just build it":

1. Simple analytics - Plausible-style pageview tracking
2. Feature flags - Basic boolean flags are trivial
3. Status pages - Static page with health checks
4. Internal tools - Admin dashboards, CRUD interfaces
5. Documentation sites - Static site generators + AI writing
6. Landing pages - AI + Tailwind + Vercel
7. Form builders - React Hook Form + AI-generated validation

Tools that remain solidly "buy"

These categories have moats that AI cannot cross:

1. Payments - Compliance and liability
2. Auth - Security expertise and ongoing maintenance
3. Hosting - Infrastructure is a full-time job
4. Email deliverability - Reputation takes years to build
5. Error tracking at scale - Aggregation and analysis is complex
6. Enterprise SSO - SAML/OIDC complexity and support

Conclusion

AI has shifted the build vs. buy curve, but it has not eliminated it. The new rule of thumb:

• •Build what AI makes trivial and has low ongoing maintenance
• •Buy what has liability, compliance, or requires 24/7 reliability
• •Hybrid for everything in between

The goal is not to build everything yourself. The goal is to spend your time—AI-assisted or not—on what actually differentiates your product.

Last updated: January 2026