Headless Bitrix cart and checkout: five things we didn't see coming
The catalog took nine days in Next.js. The cart integration took a month. Checkout took another seven weeks.
Blog
Articles on architecture, headless commerce, and practical product engineering.
Rewrite or probe: how not to burn the modernization budget
Before a large Bitrix/PHP rewrite, test the risk on a small slice: catalog, search, API, Core Web Vitals, SEO and integrations.
Risk budget before headless: what I count before a rewrite
A rewrite rarely starts with architecture. It usually starts with a sentence: "we cannot keep developing the current site anymore."
Rewrite is not a scope. It is a symptom to unpack
When someone says “we need a rewrite,” they usually aren't describing the work yet.
Should you rewrite Bitrix? Why I map scope before naming a price
When someone asks me, "How much would it cost to rewrite our Bitrix site on a normal stack?", I rarely answer with a number in the first message.
Why developers who think in business economics earn twice as much
I noticed something had changed when I stopped asking "how much does my work cost" and started asking "how much does my work cost the business."
Do not start a rewrite with a six-month estimate. Start with the first work slice
When a project already hurts, the natural request is: "Give us an estimate for the whole rewrite."
Before a Bitrix rewrite, I map the risk before I price the project
When someone comes to me with "we want to rewrite our 1C-Bitrix store on Next.js", I do not start with a price.
We Spent Three Days on AI Tooling Setup. Here's the Engineering Decision I Should Have Made First.
A colleague spent three days getting GitHub Copilot running for five developers. Everyone's VPN config differs. Billing fails through certain payment methods. The corporate account needs a foreign card. After three days: two developers work with AI, three don't. The productivity gap shows up within a week.
Why I do not give a fixed price before discovery
A fixed price before discovery sounds convenient, but in custom development it often hides the real risks: integrations, roles, data, workflows, and acceptance criteria.
TypeScript API contract for Bitrix REST: generate types, stop guessing shapes
We spent two weeks asking "what does this method actually return?" when we moved a 28,000-product catalog to a headless architecture. Open the Bitrix REST docs — they're three months behind the actual version. Open the debugger, call the method, look at the real response, infer the shape, write an interface. Next day, a teammate does the same with another method. Slightly different assumptions.
Atomic file locking in PHP: the mkdir trick that needs no Redis
PHP developers have three common approaches to preventing parallel cron execution: advisory locks in the database, Redis SETNX with TTL, or ignoring the problem and getting duplicate runs. There's a fourth option: atomic mkdir, a POSIX primitive available on any filesystem with no external dependencies.
MySQL Binlog Killed Our Cache Polling: How We Cut 2,880 Unnecessary Queries a Day
Polling the database to check for catalog changes is one of those things that works fine until it doesn't. The threshold isn't a crash. It's a number on a spreadsheet you finally decide to calculate.
When Elasticsearch is overkill for Bitrix e-commerce
I wrote about why Elasticsearch is a UX tool, not just a speed layer. Since then, three clients have asked me the same question.
I'm not tired of AI. I stopped talking to it.
I'm not tired of AI. I stopped talking to it.
One Bitrix backend, two Next.js frontends: what actually breaks
One PHP backend. Two Next.js frontends. Two domains. Two brands.
What I Check in the First 15 Minutes on a Project That's Already on Fire
People call me when things are already broken. The developer disappeared. The deadline is tomorrow. "Just a few tweaks" turned into "we have no idea what's happening anymore."
When CDN and Bitrix Composite fight each other
We added Cloudflare to a Bitrix store on Thursday evening. By Friday morning: "my cart is empty, I already added items." By Saturday: "the account page is showing someone else's data."
Vector Search for E-commerce Catalogs: When It Works, When It's Overhead
A vendor pitched vector search for our catalog. 40,000 SKUs. Elasticsearch already running — fuzzy configured, synonyms tuned, function_score boosting by margin and stock.
Why I Pay for My AI Tools Myself — While Corporates Cancel Them
Microsoft revoked enterprise Claude Code licenses for thousands of developers in a single procurement decision. One IT ticket, and the tool people had built their workflows around stopped working Monday morning.
Constraint decay in AI coding agents: why your rules vanish mid-session and how to fix it
I gave Claude Code a clear brief: refactor a PHP sync module in a Bitrix project. Type everything strictly. No mixed. No global state. All event handlers through explicit classes implementing a defined interface.
Zero-Downtime Elasticsearch Reindex: How to Update Mapping Without Stopping Your Store
We needed to add a Russian morphology analyzer to an index with 80,000 products. I had no plan for how to do it live.
Google Is Eating Your Traffic. What an E-Commerce Owner Should Actually Do
Last month I opened Google Analytics for three e-commerce projects I work with regularly. Google organic traffic: down 23% year over year. Not one project — all three. Different niches, different catalog sizes, different site ages. Same pattern.
AI context is a resource. How I stopped wasting it blindly
I spent an hour on an AI session only to discover at the end that the agent had rewritten a file we'd already fixed at the start. Not because it's broken — the context window filled up, and the model lost track of what happened early in the conversation. Since then I treat the context window like RAM: when it's full, you get swaps. So I built a session hygiene around that.
How I pitch headless to a Bitrix client: it's not about technology, it's about money
Every failed headless pitch I've seen used the same line.
Three contract clauses I added after AI changed how I deliver code
At the last project handoff, the client asked: "Can you show me where you wrote the code yourself and where the AI did it?"
Four PHP behaviors we only caught in Bitrix production
PHP has four language-level behaviors that cause production performance problems in Bitrix: session file locking, OPcache stale entries on deploy, array copy-on-write memory doubling, and non-deterministic destructor order. These aren't bugs — they're documented behavior — but they only become visible under production load.
Parallel AI agents look great in demos. Here's why I went back to one.
The demo looked convincing. Eight agents, each closing its own ticket, the Kanban board moving like something out of a pitch deck. I'd been wanting to try something like it.
Redirects Died on Deploy Day. Bitrix Didn't Warn Us.
We went headless in February. In April, our SEO consultant sent a spreadsheet: 340 broken links. Three years of redirect rules, gone the day we deployed Next.js. No errors in the logs. Next.js had no idea these rules were supposed to exist in the first place.
Elasticsearch Mapping Is Architecture, Not Configuration
For three weeks we couldn't figure out why the price filter wasn't working. Elasticsearch was up. Queries were coming in. Results were returning. But the price range — say, $15 to $50 — was being ignored completely. Products at $180 and $3 showed up side by side.
AI Agents Don't Replace Senior Engineers. They Expose Who the Seniors Actually Are.
When people tell me "AI is going to replace developers," I think about one specific bug.
Claude Code in a PHP Studio: The Honest Assessment
A year ago I wrote about what I don't delegate to AI. The list: architecture, cross-layer contracts, database schema decisions. That list still holds. But the year added something I didn't expect — a clearer picture of where Claude Code is genuinely useful.
Headless Bitrix Image Pipeline: What Breaks First in Next.js
We launched headless Bitrix + Next.js. LCP got worse.
Owning the Outcome, Not Just the Code: Three Moments That Changed How I Work
For years I thought being a good developer meant doing what you were asked — and doing it well. Task comes in, I implement it. Client accepts, I move on. That's how most people work. That's how I worked. Then three things happened.
PHP 8.4 and Bitrix in Production: What Actually Breaks
The Bitrix release notes say "PHP 8.4 supported." Our first client to upgrade staging got 47 deprecated notices on a single homepage request and a broken payment module. None of it was in Bitrix core.
Relevance isn't revenue: teaching Elasticsearch to rank by business metrics
We ran an A/B test. The control group ranked search results by text relevance. The test group used a scoring function that factored in margin, stock levels, and sell-through rate. Click-through was nearly identical. Revenue per search session was 12% higher in the business-ranked variant.
I Pay $1,800/Year for AI Tools. Here's the Exact ROI.
I added up my AI tool expenses for the year. $1,800. Did I save more than that? Honestly — I didn't know. So I sat down and calculated it.
The Non-Vibecoder's Workbench: How I Structured AI Assistance Without Losing Engineering Control
Vibecoding is when you describe a task, the AI generates code, you check that it looks right, and you deploy. I don't work that way. Not because I'm afraid of AI — Claude Code is open on my screen every working day. It's because without structure, AI in a legacy PHP project isn't acceleration. It's debt with a nice interface.
Have you actually hit the Bitrix ceiling, or are you just tired of it?
A client messaged me last year. 30,000 SKU store on Bitrix, "everything's slow," ready to migrate to headless. I asked three questions: what percentage of requests take more than two seconds? Is composite mode enabled? When did you last check slow_query_log?
Why I Keep a 'Never Again' List Between Projects
After every project I open the same note and add one line. Not "what went well" — that goes in the team retro. Just one thing: what I won't do on the next project.
Why I Ban LLMs from Client-Facing Features
I run 13 autonomous Claude tasks in my studio. They write LinkedIn posts, draft blog articles, run monitoring, send Telegram alerts. I trust them — and I sleep fine. Because if Claude writes something wrong in my name, I see it before it matters. But if it wrote that in response to a customer's question about a return policy on my client's e-commerce site? Different story. That's why I have a rule: no LLMs on client-facing features. Not yet.
The authorized user sees the login form. Bitrix is up. Next.js is up. They just can't agree on who you are.
We moved a 28,000-product catalog to Next.js. The first two days after deploy were about CSS and performance. On day three, a ticket arrived: "Authenticated users see the login form instead of their account."
Nginx in Front of Bitrix: Five Config Lines That Cut TTFB by 600ms
Most Bitrix deployments have TTFB above 700ms. Not because PHP is slow. Because the Nginx config is the one the hosting provider dropped in place years ago and nobody's touched since.
Your Search Logs Are the Best Product Doc You're Not Reading
A client asked: "What are our customers actually searching for?" I pulled up Elasticsearch and exported the top 40 zero-results queries from the past week. Three of them were exact product names. In stock. Just written differently than the catalog.
Your Client Knows You Use AI. Now They Want a Discount.
A client asked me directly, three months ago: "You use Cursor and Claude Code — why should I pay your full rate?"
I automated my blog's full production pipeline with Claude Code. Here's what actually happened.
I set up Claude Code to write and publish posts on my blog. Every 20 minutes. No approval. Fully autonomous.
Stock Sync in Headless Bitrix: Three Patterns and Why Boring Polling Wins
Three warehouses. 28,000 SKUs. A promise to the client: real-time stock data.
Three Conversations Before the Project Starts That Saved Me Six Months of Pain
My most expensive project didn't cost me money.
We plan the next Bitrix upgrade before the project launches. Here's the playbook
Bitrix upgrade lifecycle planning isn't something most teams think about at project kickoff. They think about it when a security advisory lands in their inbox on a Friday afternoon.
We rebuilt search three times. Autocomplete outperformed the first two combined.
We rebuilt search three times on one project.
AI doesn't multiply your skills. It multiplies your habits.
Last year I wrote roughly three times more code than the year before. That's true. AI tools genuinely accelerate. But a significant chunk of that code I later deleted.
What 28,000 SKUs taught me about Bitrix
I walked into the project with a bias.
If it runs without you, it's production
The first thing I wrote in my new automation system wasn't a task. It was a STOP file and an Inbox/ folder.
Why I keep human approval gates even when I could remove them
I run 15 automated tasks. Five of them will never get auto-publish — even though I could technically remove the approval gate in an afternoon.
How I write task specs for autonomous AI agents running without human oversight
When I write a task for an agent that runs on a cron at 3am, I think about the wording differently.
What we kept on Bitrix when going headless: the honest list with reasoning
When a client says "we're going headless," the first question isn't "which framework." It's: what actually stays on Bitrix?
Bitrix on Dedicated CPU: What the Production Graphs Showed After Leaving Shared Hosting
A client message: "We followed all your recommendations. OPcache is on, Redis sessions are running. We even fixed the SQL queries. But the site still goes down during evening traffic spikes."
3,000 Results Is Also Broken Search
Zero results is a red flag in the dashboard. Obvious. Gets filed as a bug.
AI Doesn't Level the Playing Field. It Multiplies What You Already Have.
When ChatGPT launched, the take I kept hearing was: juniors will code like midlevels, midlevels like seniors. The gap closes. Everyone levels up.
What I Never Give AI: A Framework From 13 Production Tasks
Seven of my thirteen production tasks run through me. Five run without me. One I'll never hand to an algorithm — not even in "show me a draft first" mode.
Local Dev for Headless Bitrix: Three Setups, One That Actually Works
The first question I get about headless Bitrix is about architecture. The second is about deployment. The third nobody asks out loud — but everyone runs into it in the first week: how do you actually develop when you don't have Bitrix on your machine?
How I spot a difficult client before the project starts
Two years ago I took a project where the first call had three signals I already knew how to read. I took it anyway — the money was good and I told myself I'd manage. Four months later I was walking out of that project. Professionally, no drama. But I'd spent months on work I shouldn't have started.
PHP-FPM pm.max_children: The Setting That Brings Bitrix Down Under Load
pm.max_children is the PHP-FPM configuration parameter that sets the maximum number of worker processes in a pool. On a busy Bitrix installation, getting this wrong is the most reliable way to turn a promotional spike into a 504 error wave — and the most reliable way to miss it during normal traffic.
When Elasticsearch Lies: Keeping Your Search Index Fresh When the Catalog Changes Daily
A customer searched, found what they needed, clicked — and got "out of stock." They left. Later, a support ticket: "your search is broken." I opened the logs. The search wasn't broken. It returned exactly what was in the index an hour ago.
I Run 13 Automations. None Use LangGraph.
My dev studio runs 13 automations. They fire every day: collecting blog topics, generating candidates, publishing articles, sending notifications, logging everything.
PHP Earns the Money. Next.js Shows It.
In a headless Bitrix + Next.js architecture, the split is straightforward in theory: Bitrix owns the data and business logic, Next.js owns the rendering. In practice, most teams get this wrong within the first year.
Monitoring 13 Autonomous Agents in Production: What to Log, Alert, and Ignore
I run 13 Claude agents on cron, fully unattended. Last week two of them failed. I found out within 2 minutes — not because I built a monitoring stack, but because I put five lines of JSONL into every task from day one.
Five things Bitrix REST API doesn't tell you before you go headless
I've spent more time with Bitrix REST API than I expected. Not because the API is broken. Because the documentation covers syntax, not behavior.
I stopped estimating in story points. Now I ask what can break everything first.
Three years ago, every project estimate started the same way. Break it into tasks, assign story points, divide by velocity, call it a deadline.
How MySQL Slow Query Log Found the Bottleneck We'd Been Chasing for Three Months
For three months we knew something was slow. LCP on the product catalog: 4.1 seconds. Where exactly — no idea.
\"Socks\" and \"knee-highs\" are the same product. Elasticsearch didn't know.
Three weeks of Elasticsearch setup (shards, replicas, mappings, custom tokenizers) got us to where fuzziness AUTO dropped zero-results from 22% to 11%. A real improvement. But 11% of searchers were still leaving empty-handed. I pulled the logs and found the problem wasn't typos. It was synonyms.
No, I Don't Scale. That's the Point.
People keep telling me to scale up. I run a boutique software agency and I do it intentionally small. I nod, say nothing, and don't change a thing. Not because I'm lazy. Because I tried.
AI Agent ROI: How I Calculate It Before the First Line of Code
When a client says "I want an AI agent to handle order processing," I ask one question: how much does processing one order cost right now?
Cache Invalidation in Headless: How Next.js Learns When Bitrix Updates a Product
The complaint came on day three after the headless launch. A store manager updated a price in Bitrix at 10:47. A customer added the product to their cart at 11:20 — at the old price. The Next.js page was cached for one hour.
Boring stack is a brave call
Three months ago a developer messaged me: "You're still writing PHP? Isn't that a waste of your time?"
PHP File Sessions Took Down Our Server at Peak Load. Here's What We Found.
Our server went down at 23:00. Right in the middle of a marketing promotion.
I write a spec before asking AI to write code. Here's why.
I timed it. When I write a spec before opening Claude Code, an iteration takes around 40 minutes. When I skip straight to the prompt, it's closer to two and a half hours and three rollbacks.
Frontend deploys in 3 minutes, backend takes 40: managing deploy velocity in headless Bitrix
We went headless. The frontend started deploying in 3 minutes. The backend didn't.
\"Samsunk phone\" returned zero results. I found it before the client did.
One of the first queries after we launched new search on a 28,000 SKU catalog: "samsunk phone."
I stopped estimating by hours. Here's how I price projects by risk now.
When a client asks "how much will this cost?", the instinct is to estimate hours. Multiply by rate. Add a 20% buffer. Send the number.
How I trust AI agents in production: 3 patterns from 13 cron jobs
When I handed 7 of 13 cron jobs to Claude, the first thing I built wasn't a prompt. It was a STOP file and an Inbox folder.
Three checks before any headless project
The first question I ask before any proposal: "Who's editing content after we're done, and where?"
I stopped interviewing developers. Here's what I do instead.
In 2020 I hired a developer who nailed the architecture explanation in the interview, answered every PHP question correctly, and impressed two people on the team. Four months later I let him go. Not because he was incompetent in the abstract — he just couldn't work in our actual context.
How PHP OPcache Silently Degrades Bitrix in Production (and the 3-Line Fix)
For three months we chased a bottleneck in a Bitrix store. Rewrote MySQL indexes. Added Redis caching where it hadn't been. Pages got a bit faster, but the catalog still hung at 800-900ms on production with no obvious reason.
Zero results as a product backlog: what your search logs are telling you
We added Elasticsearch to a 28,000 SKU catalog and assumed the hard part was done. Search works, products show up, response times are fine. A month later I opened the no-results query logs.
What 'project done' means for a senior engineer (not a PM)
A project is done when the last commit hits prod. That's how juniors think about it.
I let AI review our code for 3 months. Here's what it consistently misses.
AI code review tools are good at what they can see — syntax, patterns, obvious errors. They consistently miss what requires system context: cache dependencies, business logic hidden in refactors, and technical debt that only shows at scale.
Five questions I ask before proposing headless to a client
In the past two years I've turned down headless three times. Not because I don't believe in it — I've built it, I know what it delivers. But each time, five questions made the answer obvious before we touched a wireframe. The fourth client got the full Next.js + Bitrix split. It's one of the best ecommerce projects I've worked on.
Tech debt in plain money: how I talk refactoring to non-technical clients
Three times I explained refactoring by saying "architecture" — and three times I got a polite "sure, but let's ship features first." Then I changed one thing: instead of "architectural debt," I said "this component adds about 6 hours to every new delivery type we add. Last quarter that was 18 hours we didn't have to spend." The client said: "Okay, take a week."
3 Months With MCP: What Actually Changed in My Engineering Workflow
I set up four MCP servers in one evening. Then removed two. Added one different one. Three months later I know what Model Context Protocol is: not a smarter AI. Less friction at specific handoff points.
When headless is the wrong answer
I build headless sites on Next.js + Bitrix. I've migrated a catalog of 28,000 SKUs. I turned down a $40K contract because rewriting a working monolith made no sense. And when a client walks in asking for headless, my first question is always: "Why headless, exactly?"
Cache warming via Cron: boring, cheap, production-proven
Every night at 02:00, our cache resets.
Filters that sell: what we changed and what it did to conversion
The color filter was there. It sat at position 22 in the sidebar.
My server is 8 years old and I won't rewrite it. Here's why.
A client came to me with a request: "We need to rewrite the backend. It's old." I asked: "What specifically is broken?" Pause. "Well... it's old."
The bug Claude wrote. Seven days in production.
The code looked correct. Tests passed. CI was green.
Headless isn't about speed. It's about deploy independence.
Three years ago a client messaged me: we found a critical vulnerability in the payment module. How soon can we update Bitrix?
I publish a blog, but I build my audience on LinkedIn. Here's why.
Three weeks after launching ivanpin.com, I checked the traffic sources. LinkedIn sent orders of magnitude more visits than organic search. The site was three weeks old — that's normal. Young domains don't rank. But I kept thinking: what happens when indexing stabilizes?
Bitrix doesn't slow down. The way teams use it does.
Every third conversation about Bitrix starts with "it's slow." I stopped arguing. I ask to see the profiler instead.
I let Claude write tests. I don't let it choose architecture.
Claude wrote 340 lines of tests for me in eight minutes. Good tests. I'd have spent two hours on them. But when I asked it to suggest a module structure for a new Bitrix project, it produced something symmetric, logical, and completely wrong for our context. That gap became my working definition: where Claude's job ends and mine begins.
I turned down a $40K rewrite contract. The logs told me why.
The call was straightforward. A client wanted their Bitrix shop rewritten from scratch.
I stopped closing tickets. I started closing risks.
Three years ago I could proudly show 40 closed tickets in a sprint. The client was still unhappy.
Elasticsearch is not a fast database. It's a UX tool.
We spent three weeks on Elasticsearch. Two of those weeks were infrastructure: mapping, shards, replication, Russian morphology analyzers. Everything worked.
SSI automation. How I built 13 cron jobs without getting banned from LinkedIn.
In one week my LinkedIn SSI dropped from 38 to 37. I'm fine with that. I just finished building a system of 13 cron jobs, and the first things I put in were a STOP file and an approval folder.
Claude Code + Obsidian. How I stopped losing project documentation between projects.
I run seven projects in parallel across four stacks. The docs for each one are current. Not because I'm tidy. Because I no longer write them.
Modernizing a 1C-Bitrix Monolith Without a Risky Rewrite
How do you modernize a 28,000-product 1C-Bitrix store without a risky rewrite? In this case study, I break down a Headless migration using Next.js + Elasticsearch that improved performance, preserved SEO, and kept the business running.