Viprasol Blog

SaaS Email Verification: Double Opt-In, Token Expiry, Resend Cooldown, and Email Change Flow

Build a complete email verification system for SaaS. Covers double opt-in flow, secure token generation with SHA-256 hashing, 24-hour expiry, resend cooldown, email change verification with old address confirmation, and React email templates.

PostgreSQL Logical Decoding: Change Data Capture, Debezium, and Real-Time Data Pipelines

Implement Change Data Capture with PostgreSQL logical decoding. Covers wal2json and pgoutput plugins, Debezium connector setup, consuming WAL events in Node.js, replication slot management, lag monitoring, and building real-time sync pipelines.

React Data Tables: TanStack Table v8, Server-Side Sorting, Filtering, and Pagination

Build production data tables in React with TanStack Table v8. Covers server-side sorting, filtering, and cursor pagination, column visibility, row selection with bulk actions, column pinning, and virtualized rows with TanStack Virtual.

AWS ElastiCache Redis: Caching Strategies, Session Storage, Rate Limiting, and Pub/Sub

Use AWS ElastiCache Redis for production caching, session storage, rate limiting, and pub/sub in Node.js applications. Covers cache-aside pattern, write-through, Redis Cluster vs Replication Group, Terraform setup, and ioredis TypeScript patterns.

Next.js Error Handling: error.tsx, not-found.tsx, Global Errors, and Structured Logging

Implement comprehensive error handling in Next.js App Router. Covers error.tsx reset boundaries, not-found.tsx with notFound(), global-error.tsx for root layout errors, structured error logging with Pino, Sentry integration, and error classification.

SaaS Usage Analytics: Event Tracking, Retention Cohorts, Feature Adoption, and Dashboards

Build a production SaaS usage analytics system. Covers server-side event tracking, retention cohort queries, feature adoption funnels, DAU/WAU/MAU calculations, and building an internal analytics dashboard with PostgreSQL window functions.

PostgreSQL Row Versioning: Optimistic Locking, Lost Update Prevention, and Version Columns

Implement optimistic locking in PostgreSQL with version columns to prevent lost updates. Covers version integer patterns, xmin system column, Prisma optimistic locking, conflict detection in TypeScript, and when to choose optimistic vs pessimistic locking.

React Toast Notifications: Queue System, Variants, Auto-Dismiss, and Action Buttons

Build a production toast notification system in React without a library. Covers useToast hook, notification queue with deduplication, multiple variants (success/error/warning/info), auto-dismiss with progress bar, action buttons, and accessibility.

AWS ECR Image Scanning: Vulnerability Detection, Trivy CI, SBOM, and Image Signing with Cosign

Secure your container images with AWS ECR enhanced scanning, Trivy in CI/CD pipelines, Software Bill of Materials (SBOM) generation, and Cosign image signing. Covers Inspector integration, CVE reporting, and Terraform setup.

Next.js Streaming Responses: Server-Sent Events, AI Response Streaming, and Route Handlers

Stream responses from Next.js route handlers using Server-Sent Events. Covers ReadableStream setup, AI completion streaming with the Vercel AI SDK, chunked transfer encoding, client-side EventSource, and abort handling.

SaaS User Impersonation: Admin Session Takeover, Audit Logging, and Safe Exit

Build a secure user impersonation system for SaaS admin dashboards. Covers admin session takeover without exposing passwords, impersonation audit trail, exit impersonation button, and permission guards to prevent privilege escalation.

PostgreSQL Generated Columns: STORED Computed Values, Search Vectors, and Automated Denormalization

Use PostgreSQL generated columns for automated computed values. Covers GENERATED ALWAYS AS STORED syntax, tsvector search vectors, full name concatenation, data validation expressions, comparison with triggers, and Prisma integration.

React Keyboard Shortcuts: Global Hotkeys, Command Palette, and Focus Management

Implement keyboard shortcuts in React applications. Covers useKeyboardShortcut hook, global hotkey registration, command palette with fuzzy search, modifier key detection, shortcut conflict prevention, and accessibility considerations.

Next.js Web Vitals: Measuring and Optimizing CLS, LCP, and INP

Measure and optimize Core Web Vitals in Next.js. Covers LCP optimization with priority images and preloading, CLS prevention with aspect ratios and font loading, INP improvement with useTransition and scheduler.yield, and sending vitals to analytics.

PostgreSQL Advanced Indexing: Covering Indexes, Expression Indexes, Index-Only Scans, and Bloat

Master advanced PostgreSQL indexing. Covers covering indexes with INCLUDE, expression indexes for computed values, index-only scans, partial indexes, index bloat monitoring and REINDEX CONCURRENTLY, and multi-column index column ordering.

React File Drag-and-Drop Upload: Progress Tracking, Multi-File Queuing, and Validation

Build a production file drag-and-drop upload component in React. Covers drag-over states, multi-file queue management, upload progress with XMLHttpRequest, file type and size validation, presigned S3 URLs, and accessible keyboard file input.

AWS Lambda in VPC: RDS Access, NAT Gateway vs Interface Endpoints, and Cold Start Impact

Run AWS Lambda functions inside a VPC to access RDS and private resources. Covers VPC configuration, security groups, NAT gateway vs VPC interface endpoints for internet access, cold start impact, and Terraform setup.

Next.js Environment Variables: .env Hierarchy, Runtime vs Build-Time, Secret Injection, and Vercel

Master Next.js environment variables. Covers .env file hierarchy and precedence, NEXT_PUBLIC_ prefix for client exposure, runtime vs build-time variables, secret injection in Docker and AWS ECS, Vercel environment management, and common mistakes.

SaaS Payment Failure Handling: Dunning, Retry Logic, Grace Periods, and Payment Method Updates

Build robust payment failure handling for your SaaS. Covers Stripe dunning with smart retries, grace period enforcement, in-app payment method update flow, failed charge webhooks, and account suspension logic.

PostgreSQL Backup Strategy: pg_dump, WAL Archiving, Point-in-Time Recovery, and RDS Automated Backups

Design a production PostgreSQL backup strategy. Covers pg_dump for logical backups, WAL archiving with pgBackRest for continuous backup, point-in-time recovery (PITR), RDS automated backups, backup testing, and retention policies.

React Infinite Scroll: Intersection Observer, React Query Infinite, and Cursor Pagination

Build performant infinite scroll in React with Intersection Observer and React Query useInfiniteQuery. Covers cursor pagination, loading states, error recovery, virtual scrolling for large lists, and accessibility considerations.

AWS IAM Least-Privilege Design: Policy Patterns, Condition Keys, and Terraform

Design AWS IAM policies following least-privilege principles. Covers resource-level permissions, condition keys for MFA and region locking, role chaining, service-linked roles, permission boundaries, Terraform IAM modules, and common over-permissive patterns to avoid.

Next.js API Rate Limiting with Upstash Redis: Per-User, Per-IP, and Sliding Window Algorithms

Implement API rate limiting in Next.js with Upstash Redis. Covers sliding window and fixed window algorithms, per-user and per-IP limits, rate limit headers, middleware-based limiting, and cost-per-endpoint limits for LLM APIs.

SaaS CSV Export: Streaming Large Datasets, Background Jobs, and Presigned Download URLs

Build production CSV export for your SaaS. Covers streaming CSV generation with Node.js streams, background job processing for large datasets, S3 presigned download URLs, progress tracking, and email notification on completion.

AWS CloudWatch Logs Insights: Query Patterns, Dashboards, Alarms, and Structured Logging

Master AWS CloudWatch Logs Insights for production observability. Covers structured JSON logging from Node.js, Logs Insights query syntax for errors and latency, CloudWatch dashboards, metric filters, and alarm configuration with Terraform.