For React and Node.js engineers
Where state lives, where the server boundary goes, what to test, what to log. I'll show you how senior engineers make these calls, with the code to avoid and the code to prefer. Start with two free playbooks.
Production-Grade React Architecture Playbook (6 pages). Where state lives, how to test it, when to memoize.
Production-Grade Node.js Architecture Playbook (7 pages). Where data lives, query builder or ORM, what never to log.
export function OrderSummary({ id }) { const [order, setOrder] = useState(null); const [total, setTotal] = useState(0); useEffect(() => { fetch(`/api/orders/${id}`) .then((r) => r.json()) .then((o) => { setOrder(o); setTotal(sum(o.items)); }); }, [id]); return <Summary order={order} total={total} />;}// Server Component: runs on the serverexport async function OrderSummary({ id }) { const order = await getOrder(id); const total = sum(order.items); return <Summary order={order} total={total} />;}// loading.tsx and error.tsx handle the restSpoke at GitNation, Geekle, React Day Berlin and DevTalks Romania
The problems
These four come up again and again in React and Node codebases. All four have a fix you can learn.
Agents copy the patterns already in your codebase, good ones and bad ones. Reviewing their code is now the job, and it takes judgment about structure.
The Conscious React and The Conscious Node, with AI rules files for Claude Code, Cursor and Copilot
Components grow a prop for every design tweak. The components/ folder turns into a junk drawer. Nobody can say where new state should go.
The Conscious React, chapters 1 and 2
You ship features every week. When the talk turns to trade-offs (where data lives, query builder or ORM, when to split a service), you don't have the words yet.
The free React and Node.js playbooks
No timeout on the outbound call, a retry that charges the customer twice, logs nobody can search. Production problems start as design decisions.
The Conscious Node, plus the weekly issue
Drag the slider to ship more features. Flip the switch to see the same app built with the book's rules. Hover or tap a component to trace its wires.
15 wires; the cart lives in 3 places
The path
Start free and go deeper when you're ready, with real production code at each step.
Decision trees for the calls you make every week, and the 10 rules senior engineers follow. Free, 6 or 7 pages.
The T-Shaped Dev covers one real problem per issue, with the code to avoid, the code to prefer and why.
The Conscious React has 100+ tips and The Conscious Node has 157. Every tip shows what to avoid, what to prefer and the reason.
The Complete Packages ship CLAUDE.md, AGENTS.md and .cursorrules in every repo, so Claude Code, Cursor and Copilot write code that follows the book.
A real sample
Tip 2.23 · The Conscious React · Component Design
When a component grows a prop for every label, callback and visible-or-not flag, you're configuring it instead of composing it. Each design tweak adds another prop, the type signature swells, and the internals fill with conditional logic for every combination. The cure is composition, with named slots in place of a growing props list.
<Modal title="Confirm" showHeader showFooter confirmText="OK" cancelText="Cancel" onConfirm={handleConfirm} onCancel={handleCancel}/><Modal> <Modal.Header>Confirm</Modal.Header> <Modal.Body>Are you sure?</Modal.Body> <Modal.Footer> <button onClick={handleCancel}>Cancel</button> <button onClick={handleConfirm}>OK</button> </Modal.Footer></Modal>Expose slots and let the consumer compose. The modal stops growing props as the design grows, and each slot is independently controllable.
That's 1 of 100+ tips in The Conscious React. The Conscious Node has 157 more in the same format.
Get 3 more tips freeThe ladder
Each step builds on the one before, and you pay only when you want to go deeper.
The decision trees for state, data, testing and logging, plus the 10 rules of senior React and of senior Node.
The book alone, in PDF, EPUB and MOBI. The Conscious React has 100+ tips across 6 chapters for React 19, Server Components and the Compiler. The Conscious Node has 157 tips across 10 chapters on architecture, APIs, data, errors, security, testing and performance.
Runnable Avoid and Prefer examples, case studies, production-ready starters and AI rules files in every repo. React has 4 repos, Node has 3.
The JavaScript Architect Bundle
Both books, all 7 companion repos and the AI rules files. Save $29 on the two Complete Packages.
Every purchase comes with a 30-day money-back guarantee and lifetime updates.
Proof
"It is a fantastic and easy read with simple to follow guidelines illustrated with examples. The book has been really beneficial and practical for me from day one."
"Petar's book is excellent for React developers at all skill levels and deserves a spot on every React shop's shelf. Each page offers short, simple, and applicable advice."
"Great newsletter to help you level up as an engineer! Petar shares very practical insights in a very detailed and understandable way."
"By following the best practices mentioned, I now better know how to transform my code from being bloated, unoptimised and messy to being organised, structured and more easily scalable. And thanks to the included explanations I can understand the “why” part of the learning process."
About
I've spent 8+ years building production systems at Fortune 500 companies in cloud, finance and travel, and I've been the CEO and CTO of startups. I've mentored developers from junior to senior to architect, and I wrote two books about that road: The Conscious React and The Conscious Node.
Every promotion I got came down to one shift. I stopped writing code and started solving problems. That's what I write about every week in The T-Shaped Dev, which 30K+ engineers read.
My talk at DevTalks Romania 2026 grew out of the two books and made one argument. "AI did not kill software design. It made it more important."
Spoke at GitNation, Geekle, React Day Berlin and DevTalks Romania
React and Node.js engineers who already ship to production and want to make the architecture calls with confidence. Complete beginners will get more from the official React docs first, then this a few months later.
Start with the stack you work in every day. The free playbooks cover both. Working across the client and the server? The JavaScript Architect Bundle has both books for $89.
If you review that code, yes. Coding agents copy the patterns already in your codebase, so those patterns need to be worth copying. The books cover the decisions an agent won't make for you, and the Complete Packages include CLAUDE.md, AGENTS.md and .cursorrules files so your agents follow them too.
New deep dives as I publish them, plus an email when there's a new book, course or sale. Unsubscribe in one click.
Yes. Stripe emails a receipt right after checkout, and I send an invoice with your company details when you reply to the purchase email. For a team, write to info@petarivanov.tech for team pricing.
Use it on your real codebase for 30 days. Still no change in how you write React or Node? Reply to your receipt for a full refund.
Free, 13 pages
Get the two playbooks free, 13 pages in all. Try one decision tree on the code you're working on today.
Ready for the full set? Get both books in the Architect Bundle for $89