Codify SaaS Blog - Page 7
Code-first guides and deep dives on building B2B SaaS products, designing APIs, scaling web apps, and modernizing legacy software.
Resend vs SendGrid vs Postmark for SaaS Email
Your password reset email is part of your product. Here's how Resend, SendGrid, and Postmark compare on the things that actually matter for transactional email — deliverability, developer experience, and 2026 pricing (including SendGrid's retired free tier).
Prisma vs Drizzle ORM for SaaS in 2026
Drizzle is a thin type-safe SQL wrapper; Prisma is a schema-driven ORM with the best DX in the ecosystem. The cold-start gap that defined this debate just narrowed in Prisma 7. Here's the honest 2026 comparison and which one to pick for your SaaS.
Monolith vs Microservices for a SaaS Startup: Why Monolith First
Microservices solve an organizational problem you don't have yet. Here's why a modular monolith ships faster for an early SaaS, the real cost of going distributed too early, and the actual signals that justify splitting.
BullMQ vs Agenda: Node.js Job Queues for SaaS
BullMQ, Agenda, or Bee-Queue? The choice comes down to your data store and your throughput. Here's how Redis atomic queues compare to MongoDB polling, why retries and backoff matter more than raw speed, and which queue to pick for a NestJS SaaS.
8 SaaS Authentication Mistakes (and How to Do It Right)
Stolen credentials kick off about a quarter of all breaches. Here are eight SaaS authentication mistakes we see in real codebases — static refresh tokens, secrets in JWTs, trusting client-supplied tenant IDs — and exactly how to fix each one.
Google Workspace SSO for SaaS in NestJS
Enterprise procurement gates on SSO, and the one control that makes it real is the hosted-domain claim — skip it and your 'enterprise SSO' lets any Gmail account in. Here's Google Workspace SSO in NestJS: OIDC, the hd check, JIT provisioning, group-to-role mapping, and instant offboarding.
Cursor-Based Pagination in NestJS (Goodbye OFFSET)
OFFSET pagination quietly dies on page 500 — the database reads and throws away every row it skips. Here's cursor-based (keyset) pagination in NestJS: how it stays fast at any depth, opaque token serialization, a Prisma query, and a Next.js infinite-scroll feed.
SaaS Production Logging: Structured Logs, Centralized Guide
How to set up structured logging for a NestJS SaaS with Winston, correlation IDs, Loki or CloudWatch aggregation, alerting on error spikes, and log retention cost management.
How We Load Tested a SaaS API Before Launch — Tools, Results and What We Fixed
We load tested our NestJS SaaS API before launch using k6 — simulated user journeys, ramp-up and spike scenarios, connection pool bottlenecks, N+1 query fixes, missing indexes, and before/after throughput numbers.
Node.js Memory Leak Debugging — How We Found and Fixed a Leak in Production
Node.js memory leak debugging in production NestJS apps — a 6-hour server restart cycle, heap snapshots taken under load, Chrome DevTools analysis, unremoved event listeners found and fixed, and ongoing prevention patterns.
Horizontal Scaling for NestJS — Moving From Single Server to Multiple Instances
NestJS horizontal scaling with Redis — what breaks when you add a second instance, how to fix each problem: sessions, caches, WebSocket state, job queues, and health checks for load balancers.
Spring Boot to NestJS Migration: 12 Essential Comparisons
Spring Boot to NestJS migration guide with concept-by-concept comparisons — DI, controllers, TypeORM, testing, middleware, exception handling, and more with side-by-side code examples.