Iurii Uses: #Architecture

pikkuna.fi – AI-Powered Localization Pipeline

A production localization pipeline built entirely on the OpenAI API, with one English source of truth and SEO-aware translation prompts.

pi-pi.ee – B2B Deal & Document Portal

Internal sales portal that turns a wholesale deal into its full trade paperwork from one form: pro forma, contract, commercial invoice, packing list, CMR.

HTPBE.TECH – Internal Admin Dashboard

Role-gated admin dashboard for the HTPBE? SaaS platform – real-time KPIs, per-user quota tracking, and a zero-dependency bar chart.

pi-pi.ee – B2B E-commerce for Waterless Urinal Systems

i18n B2B e-commerce platform for waterless urinal products across 32 European countries with automated VAT handling, PDF invoicing, and CRM integration.

pikkuna.fi – E-commerce for Vinyl Curtains & PVC Products

E-commerce platform with 30 locales, product configurators, AI chatbot, and fully automated order flow: Stripe → Zoho CRM → Airtable → Mailgun → PDF.

Prevent double booking in PostgreSQL without UNIQUE or EXCLUDE: advisory locks, an overlap check, and when EXCLUDE is the right choice.

Booking slots across daylight saving time: why isValid misses skipped times and why a pinned version cannot resolve autumn ambiguity.

A decision framework for multi-region Next.js hosting: when single-region is genuinely fine and what managed platforms charge per region.

Why a Node worker writes every confirmed order to Airtable alongside the primary database, and what belongs in that snapshot and what doesn’t.

polytypo’s typography engine is a nine-rule pipeline that locates and rewrites text without ever building or reprinting an AST.

Why a Next.js e-commerce project fetches EUR/VAT reference data once per build instead of once per request or never.

How to call a logistics provider’s API from an order-processing worker, and why some booking APIs answer immediately and others don’t.

Off-the-shelf platforms like Shopify and HubSpot are the right call for most businesses – until they block the way you actually work.

How to wire an external accounting or bookkeeping API into a payment flow, and why the call belongs in the queued worker, not the webhook handler.

Build a type-safe content layer with Velite: Zod schemas for MDX and JSON, computed fields, one typed import, and a related-posts codegen step.

Batch PDF generation in Node.js without OOM: concurrency limits, back-pressure, releasing renderers between docs, and why Promise.all(map) fails at scale.

B2B quote-to-order flow in Next.js: RFQ → quote → order state machine, per-deal line items, guarded transitions, and quote conversion without data drift.

Prevent overselling under concurrent checkouts: reservations vs hard decrements, SELECT FOR UPDATE, deadlock-safe multi-line carts, and the payment window.

Gated B2B pricing in Next.js: per-account price lists and server-side access control so prices never leak to crawlers.

Build an internal CRM on Supabase: schema, RLS policies, Next.js App Router frontend, realtime subscriptions, and an honest look at where the weekend ends.

Rewrite or stabilise a legacy codebase? A practical decision framework: when stabilisation wins, when rewrite is justified, and the Strangler Fig middle path.

Multi-tenant SaaS database design: shared schema with RLS, schema-per-tenant, and database-per-tenant – trade-offs, real pitfalls, and when to use each.

Migrating from HubSpot to a custom CRM: pre-migration sampling, data export gaps, integration cutover, and what breaks in week two. Practical guide.

OpenAI API cost optimization: where the money goes in production, prompt caching, model routing, budget controls, and observability that shows overspend.

Headless CRM comparison 2026: Twenty vs EspoCRM vs DIY on Postgres. Real trade-offs on schema flexibility, integration, cost, and ecosystem risk.

AI coding widens the gap between senior and junior developers – it amplifies existing skill.

Vibe-coded codebase problems: duplicate auth flows, tests that assert nothing, unused dependencies, security shortcuts, schema drift.

Production healthcheck endpoints: liveness vs readiness probes, dependency checks with timeouts, 200 vs 503 logic, Docker and Kubernetes config, and security.

PostgreSQL production patterns: UUID v7, soft deletes, RLS for multi-tenant SaaS, partial and covering indexes, PgBouncer pooling and migration discipline.

BullMQ vs pg-boss vs node-cron for Node.js background jobs. Trade-offs between Redis and Postgres queues, retries, deduplication, and production monitoring.

JWT vs sessions vs OAuth for SaaS: token invalidation, mobile clients, refresh token rotation, and a decision matrix to pick the right auth pattern.

MVP features that kill products before launch: roles, notifications, dashboards, multi-tenancy, onboarding. What to cut and what matters at launch.

AI document processing in production: full PDF pipeline – OCR fallbacks, structured output, validation, cost at scale. Beyond naive GPT calls.

Add AI to an existing product without a rebuild. Three integration patterns, how to pick the right one, and what production-ready AI actually demands.

Agency codebase handover checklist: first 48 hours, security triage, architecture mapping, and how to write a takeover assessment. Practical guide.

llms.txt: what it is, how AI systems actually read your site (training crawls vs. runtime vs. agents), and why adding it now costs almost nothing.

Real-time Next.js admin dashboard: TanStack Query polling, Zustand for filter state, Sentry error boundaries per panel, and a zero-dependency bar chart.

IndexNow implementation for Next.js: key generation, TypeScript client with retries, GitHub Actions workflow, and pitfalls that break submissions silently.

Migrate middleware.ts to proxy.ts in Next.js 16 without breaking auth.

React masonry layout that keeps left-to-right card order with variable heights – where the popular CSS column-count trick silently breaks.

UUID v7 vs v4 in PostgreSQL: why random UUIDs fragment B-tree indexes, how UUID v7 fixes it, benchmarks at 5M rows, and Drizzle ORM migration steps.

40+ point production SaaS checklist: auth, Stripe billing, PostgreSQL, rate limiting, email, monitoring, and security – with honest 8-week build estimates.

Stripe webhook production architecture: idempotency keys in PostgreSQL and Redis, a BullMQ queue, and signature verification in Next.js App Router.

Technical SEO built into Next.js: server-side rendering, dynamic meta tags, JSON-LD structured data, and automatic sitemap generation – no plugins, just code.

Next.js i18n for 30 languages in production, not a 2-locale demo: next-intl routing, type-safe translations and hreflang at scale.

Redis rate limiting for APIs: sliding window ZADD with Lua atomicity, in-memory fallback, multi-tier limits by IP and API key, and clear response headers.

Turborepo monorepo with Next.js and Hono, sharing one set of TypeScript types across frontend and backend.