, a meta description and JSON-LD structured data. The crawler reads it all.","Indexed! The title and description show up in results, and structured data can unlock rich results like price and rating.","Real users count too. Core Web Vitals go green: LCP ≤ 2.5 s, INP ≤ 200 ms, CLS ≤ 0.1 for 75% of visits."],"pwa-offline":["Every request from the page goes through the service worker, a doorman. Online, it fetches from the network and keeps a copy in the cache.","The train enters a tunnel. Network: gone. Usually this is where the offline dinosaur shows up.","The doorman doesn't panic: the network is down, so it answers from the cache. The page still loads, offline.","With HTTPS and a web app manifest, the site can be installed: the icon lands on the home screen and opens like an app."],"promotions":["A cart arrives: three T-shirts at $20 plus $5 delivery. Total $65. The promo engine rolls up its sleeves.","Rules are checked in priority order: 2+1, −10% over $50, free delivery over $50. On this cart all three are eligible.","The customer wants all three. But 2+1 and −10% are exclusive: they can't stack, or the shop would pay you to shop.","The engine simulates both on copies of the cart: A (2+1) = $40 + $5 = $45, B (−10%, free delivery) = $54. Lowest total wins: A.","Once the order is delivered (no refund risk), loyalty points land in a ledger: +45. Every discount is explained on the receipt."],"inventory-sync":["The very last item on the shelf. Two shoppers press “buy” at the same moment. Only one can win.","A's order reserves it first: available drops to 0 (on hand minus reserved). B sees “sold out” now, not an apology email later.","A scheduled sync job (every few minutes, never overlapping) pushes the order to the ERP, the business's back office.","A supplier delivery arrives at the warehouse: +5, booked in the ERP, which owns the official stock.","The stock sync flows back to the shop: on hand 6, reserved 1, available 5. B is back in business."],"cms":["An editor writes a new page in the admin panel. It's saved as a draft — the live site still shows the old banner.","Preview shows exactly how it will look, to staff only. Visitors see nothing yet.","The editor clicks “publish”: 403. Roles are checked on the server — editors draft, only admins publish.","The admin approves and schedules it for 09:00. Nobody has to stay up just to press a button.","09:00: it goes live, the page cache is revalidated and the site updates. No deploy, no developer — who is still asleep."],"react-native":["One TypeScript codebase: React components, state and business logic, written once.","It builds into two real apps — one for iOS, one for Android — from the same code.","Not a web page in a wrapper: <View> becomes a real UIView on iOS and a native View on Android.","A bug in the shared JavaScript? It shows up on both phones at once. $NaN for a T-shirt is a bold price.","Fix it and ship an over-the-air update: a new JS bundle, no store review. JS and assets only — native code still needs a release."],"push":["The app asks the OS for a device token — an address for this app on this phone — and the backend stores it with the user.","Something happens: the order has shipped. A backend worker sends a message for that token to FCM.","FCM (via APNs for iPhones) delivers it. Bzzz! Your server never talks to the phone directly.","Tap → a deep link (myshop://orders/42) opens the right screen, not just the home page.","An old token comes back UNREGISTERED — the app is gone. The backend deletes it instead of shouting into the void."],"store-release":["CI builds a signed release: version 2.4.0, with a build number that only ever goes up.","Testers install it through TestFlight or Play internal testing — the real store pipeline, not a debug build.","Store review. The reviewer takes their time… then the stamp: APPROVED. A ready demo account helps avoid a rejection.","No 100% on day one. A phased rollout starts at 1%, then 10%, while you watch crash-free users.","Crash spike at 10%! Halt the rollout (on iOS: pause it). Most users never even got the bad build.","Hotfix 2.4.1 passes review, crash-free users are back to normal, and the rollout continues to 100%."],"documents":["In SQL, one order is split into rows across tables: orders, items, customers. To show it again, the database JOINs them back together.","MongoDB stores the whole order as one JSON-like document, items nested inside. One read gives the screen everything it needs.","Need a new field? Just add it, no blocking migration. (Schema validation still keeps the data honest.)","But a join-heavy report, like revenue by customer city, runs $lookup into another collection for every order. The robot is sweating.","Fix: shape documents around how you read them and index the fields you filter by. Truly relational reporting is still SQL's home turf."],"columnar":["The question: total sales amount. The table has a billion rows, each with date, country, url and amount.","A row store keeps each row together, so to sum one column it drags every column of every row off disk. Slow and sweaty.","A column store keeps each column in its own file. ClickHouse reads only “amount” and ignores the rest.","Similar values sit side by side, so the column compresses really well. ClickHouse chews through billions of rows per second: the sum is back in a blink.","Inserts: thousands of tiny INSERTs cause “too many parts”. Send big batches (thousands of rows, about once a second) and everyone's happy."],"llm":["Your app sends the LLM API a prompt: a system message with the rules, plus the user's question.","Text becomes tokens, chunks of roughly 3–4 characters. You pay per token, in and out, so the meter starts ticking.","The model writes one token at a time, and streaming sends each piece the moment it's ready. No staring at a spinner.","It needs real data, so it returns a tool call: structured JSON with arguments. Your code runs get_order, sends the result back, and the answer follows.","Too many requests? 429: slow down. Retry with exponential backoff (1 s, 2 s, 4 s…), honour retry-after, and it goes through."],"ml-train":["Supervised learning starts with labelled examples: photos tagged “cat” or “dog”. A few are locked away as a test set. No peeking.","Training: the model guesses, compares with the label and adjusts itself. Repeat many times, and the errors drop.","Inference: a photo it has never seen. The model says “dog” with 94% confidence. That's the whole point.","Overfitting: trained too hard, it memorised the training photos (100% there!) and is lost on new data. A cat in a party hat? “Dog??”","The fix: a simpler model or more data, then an honest exam on the held-out test set. Train 95%, test 93%: a small gap means it generalises."],"gdpr":["Consent banner: only strictly necessary cookies are on by default. Analytics and ad cookies wait for a “yes”. This one got bounced.","Data minimisation: collect only what you need. Need to know they're an adult? Ask “18+”, not a birth date. Shoe size? Nobody asked.","“Download my data”: a data map knows every place the user's data lives, so the export is complete and on time (usually within a month).","“Delete my account”: erasure reaches the database, caches and third-party processors. Backups age out on a known schedule; restores re-apply deletions.","Know what you hold and why, collect less, honour export and delete. The regulator nods. (A practical engineering view, not legal advice.)"]},"terminal":{"open":"Open terminal","close":"Close terminal","title":"Terminal","welcome":["Welcome to ghalumyan.dev — the terminal version.","Type help to see the commands. Esc or exit closes it."],"tryLabel":"Try","keys":["Tab","complete","↑↓","history","Esc","close"],"pill":"Terminal mode","help":{"title":"Commands","items":[["help","list of commands"],["about, whoami","who Mher is"],["experience","career timeline"],["skills","tech stack by area"],["projects, ls projects","case studies"],["open <project>","open a case study"],["play [game]","list games or open one"],["codle","today's word game on play.ghalumyan.dev"],["learn","list of lessons"],["contact, hire","how to reach Mher"],["cv","download the CV (PDF)"],["lang en|hy|ru","switch the site language"],["ask <question>","ask the AI about Mher's work"],["clear, exit","clear the screen / close"]],"tip":"Tab completes commands and names, ↑/↓ shows history."},"notFound":"command not found: {cmd} — type help","usage":"usage: {usage}","experience":"Experience since {year}","commits":"Commits by year","skills":"Skills","projects":"Projects — open <name> to read one","noProject":"no project called {name} — try ls projects","opening":"Opening {name}…","games":"Games — play <name> to open one","noGame":"no game called {name} — try play","lessons":"Lessons ({n})","contact":["Email: {email}","Contact page: {url}","Mher usually replies within one working day."],"cv":"Downloading the CV…","lang":"Switching to {lang}…","noLang":"unknown language: {lang} — use en, hy or ru","asking":"Thinking…","sudo":"Nice try 😄 You don't have root here.","rm":["Deleting everything…","Just kidding. Everything is safe."],"vim":["You opened vim. To quit: press Esc, type :q! and press Enter.","(This terminal has no vim, so you're free already.)"],"coffee":"Here you go. ☕","hello":"Hello! 👋 Type help to see what I can do."},"ask":{"button":"Ask my AI about my experience","title":"Ask my AI","intro":"An AI assistant that answers questions about Mher's work, using only this site's content.","placeholder":"Ask about projects, skills, experience…","send":"Send","close":"Close","you":"You","ai":"AI","chips":["What projects has Mher built?","Has he worked with POS systems?","What is his tech stack?","How can I hire him?"],"note":"AI answers can be wrong. For anything important, email Mher.","soon":"Coming soon","soonText":"The AI assistant is not switched on yet. Meanwhile, email Mher: {email}","error":"Something went wrong. Try again, or email Mher: {email}","limit":"You've reached the question limit for now. Please try again later, or email Mher: {email}","tooLong":"Please keep the question under {n} characters.","refusal":"I can only answer questions about Mher's work, skills and projects."},"tools":{"meta":{"title":"Free web tools","description":"Free tools for people who build websites: check how your links look when they are shared, and what to fix."},"hero":{"eyebrow":"Tools","title":"Free tools","accent":"for better websites.","intro":"Small, free tools I built while working on real projects. No sign-up, nothing stored."},"open":"Open tool","linkPreview":{"meta":{"title":"Link Preview Checker — test Open Graph tags","description":"Paste a link and see how it looks on Google, Facebook, LinkedIn, X, Telegram and WhatsApp. Checks og:title, og:image, twitter:card and gives copy-ready tags."},"name":"Link Preview Checker","idea":"See how any link looks when shared on Google, Facebook, LinkedIn, X, Telegram and WhatsApp — and what to fix.","hero":{"eyebrow":"Free tool","title":"Link Preview Checker","intro":"Paste a link to see how it looks when shared, with a checklist of what to fix and the tags to copy."},"label":"Paste a link","placeholder":"https://your-site.com/page","check":"Check","checking":"Checking…","redirects":"Followed {n} redirect(s) to {url}","errors":{"invalid":"That doesn't look like a link. Try something like https://example.com.","blocked":"This address can't be checked. Only public websites on ports 80 and 443 are allowed.","notfound":"This domain doesn't exist or can't be found.","timeout":"The site took too long to answer (more than 5 seconds).","status":"The page answered with HTTP {status}, so there is no preview to show.","nothtml":"This link isn't a web page (it's a file or an API).","failed":"The page could not be loaded. Try again in a moment.","limit":"You've checked a lot of links. Please try again in an hour."},"previews":{"title":"Previews","google":"Google search","facebook":"Facebook & LinkedIn","x":"X (Twitter)","message":"Telegram & WhatsApp","noImage":"No image","note":"Simplified previews: each platform crops and styles cards in its own way."},"checklist":{"title":"Checklist","summary":"{pass} passed · {warn} warnings · {fail} to fix","pass":"Pass","warn":"Warning","fail":"Fix"},"items":{"ogTitle":{"label":"og:title","fix":"Add an og:title: the headline shown on the card."},"ogDescription":{"label":"og:description","fix":"Add an og:description: one or two sentences under the headline."},"ogImage":{"label":"og:image","fix":"Add an og:image: a 1200×630 picture, or the card will have no image."},"ogUrl":{"label":"og:url","fix":"Add og:url with the page's canonical address, so shares count for one URL."},"ogType":{"label":"og:type","fix":"Add og:type, usually \"website\" or \"article\"."},"ogSiteName":{"label":"og:site_name","fix":"Add og:site_name: your site or brand name, shown above the title."},"twitterCard":{"label":"twitter:card","fix":"Set twitter:card to summary_large_image so X shows a big image."},"title":{"label":"<title> length","fix":"Keep the <title> under 60 characters, or search results cut it off."},"description":{"label":"Meta description length","fix":"Add a meta description under 160 characters."},"imageHttps":{"label":"og:image uses HTTPS","fix":"Serve the image over https://; some apps skip http images."},"imageLoads":{"label":"og:image loads","fix":"The image URL doesn't load (status shown). Fix the path or make it public."},"imageType":{"label":"og:image is an image","fix":"The image URL returns something that isn't an image."},"imageSize":{"label":"og:image size ~1200×630","fix":"Use about 1200×630 pixels (1.91:1); smaller images show as small cards."},"imageWeight":{"label":"og:image under 5 MB","fix":"Compress the image below 5 MB (ideally under 1 MB)."},"canonical":{"label":"Canonical link","fix":"Add <link rel=\"canonical\"> pointing to the main version of the page."},"lang":{"label":"lang on <html>","fix":"Add a lang attribute, e.g. <html lang=\"en\">."},"favicon":{"label":"Favicon","fix":"Add a favicon (<link rel=\"icon\">); messengers show it next to the link."}},"fix":{"title":"Copy-ready fix","intro":"Paste these tags into the <head> of the page. Check the values before you publish.","none":"Nothing to add: all the key tags are already there.","copy":"Copy","copied":"Copied","imagePlaceholder":"https://your-site.com/og-image.png"},"article":[{"title":"What is Open Graph?","paragraphs":["Open Graph is a small set of meta tags in a page's <head>. When someone shares a link, Facebook, LinkedIn, Telegram, WhatsApp, Slack and many other apps read these tags to build the preview card: og:title for the headline, og:description for the text and og:image for the picture.","X (Twitter) reads its own twitter:card tag first and falls back to Open Graph for the rest. Google uses the normal <title> and meta description for search results."]},{"title":"Why do link previews break?","paragraphs":["The most common reasons: the og:image is missing, too small, behind a login or on a URL that redirects; the tags are added by JavaScript after the page loads (most crawlers don't run JavaScript); or an app still shows an old cached preview.","A relative image path like /images/card.png also causes trouble in some apps. Use a full https:// address."]},{"title":"How to fix the common problems","paragraphs":["Render the tags on the server so they are in the HTML. Use one og:image of 1200×630 pixels, under 1 MB, on a public https:// URL. Keep titles under 60 characters and descriptions under 160. Set twitter:card to summary_large_image.","After a fix, ask each platform to read the page again: Facebook's Sharing Debugger and LinkedIn's Post Inspector refresh their caches; for Telegram, send the link to @WebpageBot."]}],"faq":{"title":"FAQ","items":[{"q":"Is this tool free?","a":"Yes. There is no sign-up and the links you check are not stored. To keep it fair, each visitor can check 20 links per hour."},{"q":"Why does my preview look different on Facebook?","a":"Platforms cache previews. If you changed your tags, use Facebook's Sharing Debugger to refresh the cache, then share the link again."},{"q":"What size should my og:image be?","a":"1200×630 pixels (a 1.91:1 ratio) works everywhere. Keep important text away from the edges, because some apps crop the image."},{"q":"Can it check pages behind a login or on localhost?","a":"No. For safety the checker only reads public web pages on ports 80 and 443, and never private or local addresses."}]},"cta":{"text":"Need help fixing your site?","action":"Contact"}}}}}],"$L1f","$L20"]}],"$L21","$L22","$L23","$L24"]}]]}]]}] </article></body></html>

8:["$","html",null,{"lang":"en","className":"__variable_62111f __variable_815f8f __variable_3743d9","suppressHydrationWarning":true,"children":[["$","head",null,{"children":[["$","script",null,{"dangerouslySetInnerHTML":{"__html":"try{if(!matchMedia('(prefers-reduced-motion: reduce)').matches)document.documentElement.classList.add('js')}catch(e){}"}}],["$","script",null,{"type":"application/ld+json","dangerouslySetInnerHTML":{"__html":"{\"@context\":\"https://schema.org\",\"@graph\":[{\"@type\":\"Person\",\"@id\":\"https://ghalumyan.dev/#person\",\"name\":\"Mher Ghalumyan\",\"alternateName\":[\"Mher Ghalumyan\",\"Մհեր Ղալումյան\",\"Мгер Галумян\"],\"jobTitle\":\"Full-Stack Engineer & Technical Lead\",\"url\":\"https://ghalumyan.dev/\",\"email\":\"mailto:hello@ghalumyan.dev\",\"address\":{\"@type\":\"PostalAddress\",\"addressLocality\":\"Yerevan\",\"addressCountry\":\"AM\"},\"worksFor\":{\"@type\":\"Organization\",\"name\":\"Concept Studio\",\"address\":{\"@type\":\"PostalAddress\",\"addressLocality\":\"Yerevan\",\"addressCountry\":\"AM\"}},\"knowsAbout\":[\"Next.js\",\"React\",\"React Native\",\"Laravel\",\"Node.js\",\"NestJS\",\"TypeScript\",\"PHP\",\"Prisma\"]},{\"@type\":\"WebSite\",\"@id\":\"https://ghalumyan.dev/#website\",\"url\":\"https://ghalumyan.dev/\",\"name\":\"Mher Ghalumyan\",\"inLanguage\":[\"en\",\"hy\",\"ru\"],\"publisher\":{\"@id\":\"https://ghalumyan.dev/#person\"}}]}"}}]]}],["$","body",null,{"children":[["$","a",null,{"className":"skip-link","href":"#main","children":"Skip to content"}],["$","$L1c",null,{"children":[["$","$L1d",null,{"children":[["$","$L1e",null,{"locale":"en","dict":{"meta":{"title":"Mher Ghalumyan — Full-Stack Engineer & Technical Lead","description":"Full-stack engineer from Yerevan with 10+ years of experience: SaaS platforms, e-commerce, mobile apps and integrations with Laravel, NestJS, Next.js and React Native."},"person":{"name":"Mher Ghalumyan","firstName":"Mher","lastName":"Ghalumyan","role":"Full-Stack Engineer & Technical Lead","location":"Yerevan, Armenia"},"nav":{"home":"Home","work":"Work","learn":"Learn","services":"Services","about":"About","experience":"Experience","cv":"CV","contact":"Contact","play":"Arcade","tools":"Tools","cta":"Let's talk","menu":"Menu","close":"Close","language":"Language","skip":"Skip to content"},"ui":{"viewCase":"View case","viewAll":"View all work","readMore":"Learn more","back":"Back","next":"Next project","scroll":"Scroll","open":"Open","view":"View","drag":"Drag","yearsShort":"yrs"},"cta":{"title":"Have a product in mind?","accent":"Let's build it.","text":"Tell me about your idea, your product or your team. I usually reply within one working day.","action":"Start a conversation"},"consoleHello":"Found a bug? There are more →","footer":{"sayHi":"Have a project in mind? Say hi","rights":"All rights reserved.","tagline":"Designed by me","top":"Back to top","pages":"Pages","arcade":"Arcade","arcadeText":"Mini games for developers and a daily coding word puzzle, on play.ghalumyan.dev.","arcadeAction":"Take a break","available":"Available for selected projects"},"home":{"meta":{"title":"Mher Ghalumyan — Full-Stack Engineer & Technical Lead","description":"I design, build and launch SaaS platforms, online stores, mobile apps and business systems — from database to deployment."},"hero":{"badge":"Available for selected projects","greeting":"Hi, I'm","titleLines":["I build products","that ship and scale."],"intro":"More than ten years of building real software for real businesses: SaaS platforms, online stores, iOS & Android apps and the back offices that run them — designed, engineered and launched end-to-end.","primary":"See my work","secondary":"Download CV"},"intro":{"eyebrow":"In short","title":"One engineer across the whole product — from the data model to the last animation frame.","text":"I lead and build products where the hard part isn't one screen but the system behind it: discount engines that must always find the best price, apps that keep selling when the internet drops, stores that stay in sync with accounting. I like owning that whole path, and I like making it feel simple.","stats":[{"value":10,"suffix":"+","label":"Years of development experience"},{"value":7100,"suffix":"+","label":"Commits across production repos"},{"value":13,"suffix":"","label":"Products shipped and maintained"},{"value":5,"suffix":"","label":"iOS & Android apps on one shared template"}]},"work":{"eyebrow":"Selected work","title":"Systems that real businesses run on every day.","note":"Client names are omitted under NDA — every case study describes real work I led or built."},"services":{"eyebrow":"What I do","title":"From first sketch to production — and after."},"process":{"eyebrow":"How I work","title":"A calm, predictable process.","steps":[{"title":"Discover","text":"I start with the business: who uses it, what must never go wrong, what success looks like in numbers. Then I map the riskiest parts first."},{"title":"Design the system","text":"Data model, API contracts, roles and edge cases are written down before the first production line — so the team builds the same thing."},{"title":"Build in small steps","text":"Short, reviewed increments behind clear acceptance criteria. You can see and test progress every week, not at the end."},{"title":"Launch & grow","text":"Monitoring, performance budgets and a release process — then analytics, automations and the features that came from real usage."}]},"timeline":{"eyebrow":"Path","title":"The last six years: bigger systems every year.","action":"Full experience"}},"work":{"meta":{"title":"Work","description":"Case studies: a multi-tenant POS SaaS, ordering platforms, ERP-synced e-commerce, CRM systems and mobile apps — anonymized, real work."},"hero":{"eyebrow":"Selected work","title":"Thirteen products.","accent":"Real systems, real users.","intro":"Every project below is real, shipped work. Client names are omitted under NDA — the architecture, the decisions and the numbers are real."},"filters":{"label":"Filter projects","all":"All","saas":"SaaS & platforms","commerce":"E-commerce","mobile":"Mobile apps","web":"Websites"},"labels":{"role":"Role","years":"Years","platforms":"Platforms","share":"My share","challenge":"The challenge","approach":"How I solved it","features":"What it does","results":"Results","stack":"Stack","integrations":"Integrations","nda":"Details, names and visuals are generalised to respect client confidentiality. Happy to walk through the architecture in a call.","sharePrefix":"of commits","more":"Also contributed to"},"platforms":{"web":"Website","admin":"Admin panel","mobile":"iOS & Android","desktop":"Desktop app","api":"API","hub":"Offline hub","packages":"npm packages"},"more":[{"title":"Premium food e-shop with a recipes hub","text":"Stripe and PayPal payments with webhooks, shipping by region, refunds, admin and production setup."},{"title":"Tour-operator booking platform","text":"Bank-gateway integration, date-aware tour cart, multi-currency pricing and schema-markup SEO in 8 languages."}]},"projects":{"pos-saas":{"category":"SaaS · Point of sale","title":"Multi-tenant POS & back-office SaaS for restaurants and cafés","summary":"A platform sold to many food businesses at once: a desktop till that keeps selling offline, kitchen and queue screens, a company portal, loyalty and marketing, fiscal receipts and public APIs for their mobile apps.","role":"Co-lead engineer · API, portal, till and offline hub","challenge":"Cafés can't stop selling when the internet drops, and a SaaS can never leak one company's data into another's. The platform had to run walk-in sales offline, sync safely later, and keep many tenants strictly apart — while covering everything from menus and stock to staff, payments and loyalty.","approach":["Tenant isolation enforced twice: every query carries the company scope explicitly, and a database extension throws if a query ever forgets it. Any exception must be allow-listed with a written reason.","An offline branch hub with its own local database runs walk-in sales when the cloud is unreachable; every sync command is deduplicated per terminal, so a retry can never double an order.","A transactional outbox feeds background queues and HMAC-signed webhooks, so events are never lost between a sale and the systems that react to it.","Idempotency keys on partner orders, refunds with an explicit 'outcome unknown' state and a reconciliation job make money flows auditable.","A 'wrong tenant' test in every module's test suite — cross-tenant access must return 404, not data."],"features":["Desktop till (Electron) with device sessions, auto-update and offline mode","Kitchen, bar and queue screens with realtime updates over WebSockets","Menus, modifiers, recipes, stock, suppliers and purchase orders","Staff roles with custom permissions, shifts, attendance and day close","Loyalty programs with tiers, rewards, challenges and two-person approvals","Fiscal receipts with offline variants and retries","Scoped API keys, guest OTP login and a versioned API for client mobile apps","Schema-driven CMS, email designer and segment-based campaigns"],"results":["181-model domain and ~936 API endpoints delivered in about four months by a two-person core team","Six deployable apps and ten shared packages in one typed monorepo","The coffee-chain app in this portfolio runs entirely on its public APIs"],"metrics":[{"value":"181","label":"Data models"},{"value":"~936","label":"API endpoints"},{"value":"6","label":"Deployable apps"},{"value":"20","label":"Background queues"}]},"restaurant-ordering":{"category":"Food ordering · Web, app & admin","title":"Ordering & delivery platform for a restaurant chain","summary":"One platform for a multi-branch restaurant chain: website, iOS & Android app and a back office — with delivery zones, scheduled orders, a cashback wallet, a promotion engine and marketing automation.","role":"Tech lead · backend, admin, mobile app","challenge":"Customers order from the website and the app, for delivery or takeaway, now or later, from different branches — and every order must get the right price under overlapping discounts, the right delivery rules and the right working hours. Marketing wanted segments and campaigns on top.","approach":["A single Laravel API with controllers split into shared, web, mobile and admin layers, so both customer channels reuse the same business logic.","A promotion engine (~1,300 lines) that simulates discount combinations and guarantees the customer always gets the best valid total, with clear stacking rules.","Delivery zones resolved from map coordinates and a time-slot engine for ASAP, scheduled and takeaway orders that respects each branch's hours.","Daily-refreshed customer segments driving email, SMS and push campaigns, re-synced whenever a wallet balance changes.","A React Native app with remote force-update, a switchable API base URL for testing and a retry policy that only repeats safe requests."],"features":["Phone OTP, Google and Apple sign-in on web and native","Guest cart that merges on login, reorder and saved cards","Cashback wallet with tiers, history and vouchers","Nine payment methods incl. Apple Pay, Google Pay and local gateways","Live order status, courier and operator roles, reviews","~30 analytics reports and ~40 Excel exports for the business","Media library, blog, FAQ and per-page SEO in the CMS","Push notifications with an in-app inbox and seasonal event screens"],"results":["One backend serving three surfaces — website, mobile app and admin — in three languages","~330 API endpoints, 49 data models and 12 admin roles","I authored about 7 out of 10 commits on the platform and 8 out of 10 on the app"],"metrics":[{"value":"~330","label":"API endpoints"},{"value":"9","label":"Payment methods"},{"value":"3","label":"Client surfaces"},{"value":"68%","label":"Of commits authored"}]},"pet-commerce-erp":{"category":"E-commerce · ERP integration","title":"Pet-supplies store synced with accounting and inventory","summary":"A trilingual online store and mobile app for a pet-supplies retailer, connected to its accounting/ERP system and fiscal receipts — with real inventory, smart search, referrals and marketing automation.","role":"Tech lead · architecture, backend, storefront","challenge":"Online sales had to match the shop's accounting system exactly: prices, stock, customers, loyalty balances and fiscal receipts. At the same time the business wanted growth tools — referrals, recommendations, automated campaigns — without slowing the catalogue down.","approach":["Customer routes defined once and mounted for both web and mobile, so the two channels can never drift apart.","ERP synchronisation as scheduled, feature-flagged jobs with health alerts and a safe price-revert, switchable from the admin panel.","Pricing modelled as value objects with pack and weight sale modes, so a product can be sold per unit or per kilogram without special cases.","A referral system with invite codes, deferred deep links into the app and fraud checks before rewards settle.","A strict design-token system and an AI-assisted planner → implementer → reviewer workflow that keeps every screen consistent."],"features":["Algolia search with suggestions, synonyms and search analytics","Recommendations: 'buy again', 'recently viewed', cart suggestions","Warehouses, stock movements, transfers, suppliers and purchase orders","Loyalty balance with expiry, gifts, deals and vouchers","Abandoned-cart, balance-expiry and review-request automations","Segments, email campaigns with open/click tracking and push inbox","Reports on margin, dead stock, reorder suggestions and attribution","~35-screen mobile app with onboarding video and in-app chat"],"results":["About 110 service classes and 95 backend test files","Website, app and admin delivered in roughly twelve months","I authored ~71% of the web and backend commits"],"metrics":[{"value":"~110","label":"Service classes"},{"value":"95","label":"Backend test files"},{"value":"12","label":"ERP sync services"},{"value":"71%","label":"Of commits authored"}]},"coffee-loyalty-app":{"category":"Mobile · Ordering & loyalty","title":"Order-ahead & loyalty app for a coffee chain","summary":"An iOS & Android app where customers order ahead, pay, pick up with a QR code and collect rewards — built on the POS SaaS above, plus a careers website.","role":"Mobile lead · React Native, website","challenge":"The app had to feel instant and native while talking to a backend that was still evolving. Guests should browse freely and sign in only when needed — and land back exactly where they were.","approach":["A single adapter layer normalises every backend response, so a renamed field never touches a screen.","Screens read stores only; stores call the API — data flow stays predictable as the app grows.","Gated tabs remember the guest's place and return them there after sign-in.","A post-edit hook reports only new type, lint or translation errors against a recorded baseline, so quality can only go up.","A Figma-vs-simulator pixel check that compares built screens with the design."],"features":["OTP sign-in and guest browsing","Menus, combos, extras and recommendations","Server-side cart with price quotes and scheduled orders","Card and wallet payments, saved cards, resume pending payment","Pickup QR, order history and one-tap reorder","Points, rewards, challenges and a loyalty-card wallet","Store locator with maps, light and dark themes","Force update and maintenance mode via remote config"],"results":["~43 navigation routes and 10 stores on React Native's New Architecture","Three languages with checked key parity","Careers website with CMS vacancies and a secured application form"],"metrics":[{"value":"~43","label":"App routes"},{"value":"10","label":"State stores"},{"value":"3","label":"Languages"},{"value":"0.86","label":"React Native version"}]},"gym-crm":{"category":"CRM · Operations & mobile","title":"Gym-chain CRM with QR check-in and a member app","summary":"A back office for a multi-branch gym chain — memberships, QR check-in, front-desk payments with fiscal receipts, payroll and reports — plus a mobile app for members.","role":"Lead engineer · near-solo CRM build, member app","challenge":"Front desks need speed and zero mistakes with money: check members in, sell and freeze plans, print receipts, close the register — across branches. Members want their plan, history and QR in their pocket.","approach":["QR check-in that toggles in/out with per-branch tokens that can be regenerated, and automatic check-out at closing.","Ordered, non-overlapping scheduled jobs (unfreeze → expire → activate), so plan states never conflict.","SMS retries only on connection failures — a member never receives the same code twice.","Thermal receipt printing over the network and fiscal receipts with per-branch device pairing.","QR posters with web links that open the app or fall back to a web page."],"features":["Plans and subscriptions with freeze, cancel and trainer change","Live occupancy and check-in heatmaps","Cash register with deposits, withdrawals and daily close","Trainer and staff payroll, including prorated and reversed payments","Revenue, growth and staff-performance reports with Excel export","Push campaigns, announcements and force update in the app"],"results":["I authored 92% of the CRM's commits","31 test files and a documented release process","One platform for members, front desk and management"],"metrics":[{"value":"92%","label":"Of commits authored"},{"value":"~135","label":"API routes"},{"value":"11","label":"Scheduled jobs"},{"value":"31","label":"Test files"}]},"beauty-commerce":{"category":"E-commerce · Growth & CRM","title":"Beauty-products store with a promotions engine and marketing CRM","summary":"An e-commerce platform migrated from WordPress, with a promotions engine, store-credit wallet, customer segments, email campaigns and a full analytics suite.","role":"Lead backend engineer · promotions, CRM, analytics","challenge":"Move an existing shop off WordPress without forcing customers to reset passwords, then turn it into a growth machine: smarter discounts, targeted campaigns and numbers the owners can act on.","approach":["Password-hash compatibility so migrated customers log in with their old passwords — no reset emails, no lost customers.","A ~1,300-line promotion engine (first-order, loyalty tiers, cashback, gifts) that picks the best scenario for the customer.","Promotions, segments and campaigns designed as one loop: who to target, what to offer, what it earned."],"features":["Catalogue with brands, tags and reviews; wishlist and addresses","Store-credit and cashback wallet","Segments: abandoned checkouts, lapsed buyers, subscribers…","Queued email campaigns with unsubscribe","~30 analytics exports; per-item refunds and tracking numbers","Real-time admin updates"],"results":["Seamless migration of existing users","Promotions, CRM and analytics in one admin","I authored about half of all commits over three years"],"metrics":[{"value":"~1,300","label":"Lines of promo engine"},{"value":"~30","label":"Excel exports"},{"value":"42","label":"Controllers"},{"value":"52%","label":"Of commits authored"}]},"investment-portal":{"category":"Portal · Paid listings","title":"Investment-promotion portal with paid listings and a mobile app","summary":"A national portal where companies publish paid investment projects and investors browse them — plus a pay-per-report export-data product and, later, a companion mobile app.","role":"Backend engineer · longest-running system I maintain","challenge":"Turn listings into a product: companies submit and pay, moderators approve or reject, listings publish and expire on time, and everyone is notified at each step.","approach":["A complete listing lifecycle: submit → pay → moderate → publish → expire → notify, with scheduled expiry emails.","A paid calculator that generates an Excel export-potential report on demand.","Later, the same domain carried into a mobile app with map search and a multi-step submission flow."],"features":["Project catalogue with filters and company profiles","Registration, email verification and Google/LinkedIn/Facebook login","Customer cabinet with projects, companies and purchases","Tiered listing prices and bank-card payments","News, partners, newsletter and 11 CMS page types","Mobile app with map search, document upload and push"],"results":["Built and evolved since 2020","Three languages, 36 data models, 33 public pages","My first full year on it: 535 commits, mostly backend"],"metrics":[{"value":"2020","label":"Built since"},{"value":"36","label":"Data models"},{"value":"33","label":"Public pages"},{"value":"3","label":"Languages"}]},"game-liveops":{"category":"Games · LiveOps & merch","title":"Brand site, merch shop and LiveOps console for a mobile game","summary":"The website and merch store for a social-casino mobile game, and a LiveOps back office where the team runs tournaments, remote config, push and player support.","role":"Full-stack engineer · shop backend, LiveOps console","challenge":"The game's data lives in Firestore, not SQL — yet operators need a fast admin with search, history, analytics and safe editing of live game settings.","approach":["A hand-written, typed Firestore REST client behind a Laravel + React admin.","A remote-config editor with version history and diffs, so every change to the live game is visible and reversible.","Hourly archiving of tournament leaderboards into SQL for reporting."],"features":["Player list, details, stats, groups and moderation queue","In-app purchase browsing, exports and top-spender analytics","Tournaments with live leaderboards","Admin virtual-coin grants with a ledger","Merch shop with variants and live shipping-rate quotes","Push notifications and player problem reports"],"results":["Operators manage the live game without touching code","Every remote-config change has history and a diff","Shop maintained since 2022; LiveOps console built in 2025–26"],"metrics":[{"value":"58","label":"Console API routes"},{"value":"13","label":"Admin sections"},{"value":"2022","label":"Maintained since"},{"value":"2","label":"Payment providers"}]},"winery-club":{"category":"E-commerce · Loyalty club","title":"Winery shop with a bottle-code loyalty club","summary":"A direct-to-consumer wine shop where every registered bottle code earns points and unlocks tiers — with digital wine labels, events and a 3D-enhanced website.","role":"Frontend engineer · storefront and loyalty UI","challenge":"Connect physical bottles to a digital loyalty program, and present wine — vintages, grapes, pairings — in a way that feels premium.","approach":["Bottle registration via vintage codes → points → five loyalty tiers, synced with customer segments.","A promotion engine scoped by segment, product and variant, applied automatically or by code.","Digital e-labels per vintage with certifications and responsible-consumption information."],"features":["Wines and vintages with grapes, pairings and serving temperature","Shop with variants, cart merge and reorder","Member collections, benefits and event registration","Store-finder map","3D scene and GSAP motion on the website"],"results":["Loyalty tied to physical products, not just orders","46 data models, 33 pages, 2 languages"],"metrics":[{"value":"5","label":"Loyalty tiers"},{"value":"46","label":"Data models"},{"value":"33","label":"Pages"},{"value":"2","label":"Languages"}]},"agency-cms":{"category":"Website · Hybrid CMS","title":"Digital-agency website rebuilt on the App Router","summary":"The marketing website of a digital agency — services, portfolio, blog, careers — rewritten from the Pages Router to the App Router, with a hybrid CMS and playful 3D details.","role":"Top contributor · frontend and CMS","challenge":"Replace a live website without downtime or SEO loss, while editors keep publishing — and make it feel like a showcase of the agency's craft.","approach":["The new App Router site was built in parallel for about a year and a half, then swapped in.","A hybrid CMS: structured data in Laravel, editorial content in a headless CMS.","Contact form submissions create CRM leads and send auto-replies with matching portfolio cases."],"features":["Services with nested pages, portfolio, team, awards, careers with CV upload","Block-based case studies and blog posts","Three.js mini-game, particle cursor, Lottie and dark mode","Sitemap, robots, llms.txt and SEO redirects"],"results":["The hand-built admin here became the ancestor of the reusable admin packages","I was the top contributor across three years"],"metrics":[{"value":"55%","label":"Of commits authored"},{"value":"~290","label":"Frontend modules"},{"value":"3","label":"Years of evolution"},{"value":"2","label":"Frontend generations"}]},"package-ecosystem":{"category":"Platform · Internal packages","title":"In-house component & admin package ecosystem","summary":"The internal platform behind ~10 client sites: versioned React/Next packages for accounts, carts, checkout and forms, a config-driven admin system, and Laravel cores to match.","role":"Top contributor & maintainer","challenge":"Every new client site was rebuilding the same accounts, carts, checkouts and admin CRUD screens. That cost time and multiplied bugs.","approach":["Repeated code extracted into versioned npm packages with example apps that mirror real client sites.","A config-driven admin: describe a resource once, get list, filters, forms and media management.","A design inspector that lets designers tune CSS variables and translations live and save them back to source.","A design-token migration plan to remove thousands of lines of per-project overrides."],"features":["Account, cart, checkout and order page templates","Admin UI kit with ~20 components, media manager, rich-text, slug and tree fields","Form package with phone, select, date and upload fields","Core API client, i18n and spacing tokens","Laravel admin-core with OTP login, roles and a generic resource controller"],"results":["10 published packages reused across about ten client sites","~1,066 commits — the top contributor on the monorepo"],"metrics":[{"value":"10","label":"Published packages"},{"value":"~10","label":"Client sites using them"},{"value":"1,066","label":"My commits"},{"value":"10","label":"Example apps"}]}},"services":{"meta":{"title":"Services","description":"What I build: SaaS platforms, e-commerce, mobile apps, APIs and admin panels, payment and ERP integrations, and technical leadership with AI-assisted workflows."},"hero":{"eyebrow":"Services","title":"What I can build","accent":"for your business.","intro":"I work across the whole product, so you don't have to coordinate five specialists. Pick one area or hand me the entire system — from data model to app store."},"list":[{"title":"SaaS & multi-tenant platforms","text":"Platforms sold to many companies at once: strict tenant isolation, roles and permissions, plans and feature switches, public APIs, background jobs and audit trails.","deliverables":["Architecture & data model","Tenant isolation & roles","Public / partner APIs","Queues, webhooks, outbox","Observability"],"stack":["NestJS","Prisma","PostgreSQL","Redis","BullMQ"]},{"title":"E-commerce & growth","text":"Stores that sell and grow: catalogues with variants, carts and checkouts, promotion engines, loyalty and wallets, referrals, segments, campaigns and analytics.","deliverables":["Storefront & checkout","Promotion engine","Loyalty, wallet, referrals","Segments & campaigns","Reports & exports"],"stack":["Next.js","Laravel","Algolia","Stripe","PayPal"]},{"title":"Mobile apps","text":"iOS and Android apps in React Native that feel native: OTP login, payments, push, QR flows, maps, offline states, remote config and force update.","deliverables":["App architecture","Design system & themes","Payments & push","Store releases","Crash & analytics"],"stack":["React Native","TypeScript","Zustand","Firebase","Reanimated"]},{"title":"Websites & web apps","text":"Fast, multilingual, SEO-ready websites and web apps with motion that feels premium but never slows the page down.","deliverables":["Next.js App Router","i18n & SEO","CMS integration","Animation & 3D","Core Web Vitals"],"stack":["Next.js","React","GSAP","Three.js","TypeScript"]},{"title":"Backends, APIs & admin panels","text":"Clean APIs and back offices the business can run on: auth, roles, media libraries, content management, reporting and Excel exports.","deliverables":["REST API design","Admin panel","Media & CMS","Analytics dashboards","Tests"],"stack":["Laravel","PHP","Node.js","MySQL","React"]},{"title":"Integrations","text":"The connections that make a product real: local and international payment gateways, accounting/ERP, fiscal receipts, search, maps, SMS, email and CRM.","deliverables":["Payment gateways","ERP / accounting sync","Fiscal receipts","Search & maps","Email, SMS, CRM"],"stack":["Idram","Ameria","Stripe","Firebase","HubSpot"]},{"title":"Technical leadership & AI-assisted development","text":"Code standards, reviews, architecture decisions and an AI workflow that makes a small team ship like a big one — without lowering quality.","deliverables":["Architecture reviews","Team conventions","CLAUDE.md & agent workflows","Quality gates & hooks","Mentoring"],"stack":["Claude Code","Git","CI","Docker","Linux"]}],"labels":{"deliverables":"What you get","stack":"Typical stack"},"engagement":{"eyebrow":"Ways to work together","title":"Choose what fits your stage.","items":[{"title":"Full product","text":"From idea to launch: discovery, architecture, design system, backend, web, mobile and release."},{"title":"Team extension","text":"I join your team as a senior engineer or tech lead and take ownership of a product area."},{"title":"Audit & consulting","text":"Architecture, performance, security or AI-workflow review with a clear, prioritised action list."}]},"faq":{"eyebrow":"FAQ","title":"Questions people usually ask.","items":[{"q":"Do you work alone or with a team?","a":"Both. I can own a product end-to-end, lead a small team, or join yours. On larger platforms I usually work as tech lead next to other engineers and designers."},{"q":"Can you take over an existing project?","a":"Yes — most of my work is evolving live systems. I start with a short audit: how it's built, what's risky, what to fix first."},{"q":"Which payment and business systems have you integrated?","a":"Local and international card gateways, Apple Pay and Google Pay, Stripe, PayPal, accounting/ERP sync, fiscal receipt devices, Algolia, Firebase, SMS and email providers, HubSpot and Mailchimp."},{"q":"Do you design too?","a":"I implement designs pixel-perfectly and build design systems with tokens. For brand and UI design I work with designers — or bring one in."},{"q":"What languages can the product support?","a":"Most of my products ship in three languages (English, Armenian, Russian) — one in eight. Multilingual content and per-language SEO are standard for me."}]}},"about":{"meta":{"title":"About","description":"Full-stack engineer and technical lead from Yerevan: my story, how I think about software, my skills and my AI-assisted engineering workflow."},"hero":{"eyebrow":"About me","title":"I'm Mher —","accent":"an engineer who likes the whole picture.","intro":"Based in Yerevan. More than ten years of building software — and years of shipping products where the backend, the apps and the business rules all have to agree with each other."},"story":{"eyebrow":"Story","title":"From client websites to platforms used every day.","paragraphs":["I started as a full-stack developer in 2016 at Atom Planet, building websites and web applications for clients, then moved through Twelve to Concept Studio at the end of 2019 — where I still work and now lead. The oldest code I still maintain is from December 2020: the backend of a national investment portal — paid listings, payments, moderation, emails. It taught me that software is a chain of promises: if a company pays, the listing must publish, expire and notify on time, every time.","Since then the systems grew. A merch shop and a LiveOps console for a mobile game. An agency website rebuilt from scratch. Then the platforms that became my main work: a restaurant chain's ordering system with a promotion engine that always finds the customer's best price, an online store synchronised with accounting and fiscal receipts, a gym chain's CRM, and a multi-tenant POS SaaS that keeps cafés selling even when the internet is down.","Along the way I started turning repeated work into reusable packages, and repeated mistakes into rules. Today I lead products end-to-end — architecture, backend, web, mobile — and I build the tooling, including AI agents, that lets a small team move fast without breaking things.","I work best close to the people who own the problem. I turn business requirements into a written data model and API contract before building, work hand in hand with designers so the result matches the design, and review my teammates' code the way I want mine reviewed. The products I enjoy most have real operational stakes — money, orders, stock, people on shift — where getting the details right is the whole job."]},"numbers":[{"value":10,"suffix":"+","label":"Years of building software"},{"value":7100,"suffix":"+","label":"Commits — about half of my team's total"},{"value":11,"suffix":"","label":"Repositories where I'm the top contributor"},{"value":9,"suffix":"+","label":"Payment providers integrated"}],"principles":{"eyebrow":"How I think","title":"Principles I don't negotiate on.","items":[{"title":"Correct before clever","text":"Money, orders and permissions must be right every time. I design for the edge cases first — retries, offline, double clicks, wrong tenants."},{"title":"One source of truth","text":"Rules live in one place: one API for web and mobile, one design-token system, one promotion engine. Duplicates drift."},{"title":"Small, reviewed steps","text":"Short increments with clear acceptance criteria beat big-bang releases. Everyone sees progress; nobody gets surprised."},{"title":"Make it simple to use","text":"Complex systems should feel obvious — to the customer, to the cashier, and to the next developer who opens the code."}]},"skills":{"eyebrow":"Skills","title":"The tools I use to build.","groups":{"frontend":{"title":"Frontend","text":"Interfaces that feel fast and clear."},"backend":{"title":"Backend & data","text":"Reliable logic, APIs and storage."},"mobile":{"title":"Mobile & desktop","text":"Apps for every screen."},"infra":{"title":"Infrastructure & tooling","text":"Shipping and running in production."}}},"ai":{"eyebrow":"AI-assisted engineering","title":"I build the workflow, not just the code.","text":"On my recent products I made AI agents part of the engineering process — with the same rigour as code. On the POS SaaS, that workflow helped a two-person core team ship a 181-model platform in about four months without lowering the bar.","points":["Project rulebooks (CLAUDE.md) with design tokens, breakpoints and architecture rules","Planner → implementer → reviewer agent pipelines with acceptance criteria","Browser-verify and Figma pixel-check agents that look at the real result","Post-edit hooks that type-check, lint and verify translations on every change"]}},"experience":{"meta":{"title":"Experience","description":"10+ years of full-stack development since 2016 — roles at Atom Planet, Twelve and Concept Studio, and the last six years documented commit by commit."},"hero":{"eyebrow":"Experience","title":"10+ years in production —","accent":"since 2016.","intro":"Every role since my first developer job in 2016. The year-by-year timeline below is built from the commit history I still have access to (December 2020 onward) — earlier code lives in previous employers' repositories. No inflated titles, just what I worked on and how the work grew."},"roles":{"eyebrow":"Roles","title":"Where I've been building.","items":[{"period":"2024 — Present","title":"Technical Lead & Full-Stack Engineer","company":"Concept Studio, Yerevan","text":"Leading architecture and delivery of SaaS, e-commerce and mobile products; maintaining the studio's shared package ecosystem; introducing AI-assisted engineering workflows."},{"period":"2019 — 2024","title":"Full-Stack Developer","company":"Concept Studio, Yerevan","text":"Backends, admin panels and storefronts for portals, e-commerce and a mobile-game brand; the rebuild of the studio's own website."},{"period":"2019","title":"Full-Stack Developer","company":"Twelve company, Yerevan","text":"Full-stack development of client websites and web applications, from the database and backend to the interface."},{"period":"2016 — 2019","title":"Full-Stack Developer","company":"Atom Planet LLC, Yerevan","text":"My first developer role: three years of building websites and web applications for clients, front end and back end — where I learned to ship real software for real businesses."}]},"years":{"eyebrow":"Timeline","title":"What each year looked like.","commits":"commits","items":[{"year":"2020","text":"Oldest commit in the repositories I still maintain: backend of a national investment-promotion portal."},{"year":"2021","text":"Paid listings, payments, moderation and the admin panel of the portal — 535 commits in the project's first full year."},{"year":"2022","text":"Merch shop backend for a mobile-game brand; continued portal development."},{"year":"2023","text":"Rebuilt a digital agency's website on the Next.js App Router with a hybrid CMS."},{"year":"2024","text":"Began building the in-house package ecosystem; began the restaurant-chain ordering platform; beauty e-commerce."},{"year":"2025","text":"Restaurant platform and its mobile app, LiveOps console for a game, winery loyalty shop, pet-supplies store."},{"year":"2026","text":"Pet-store app, gym CRM and app, coffee loyalty app, and co-leading a multi-tenant POS SaaS."}]}},"cv":{"meta":{"title":"CV","description":"Curriculum vitae of Mher Ghalumyan — full-stack engineer and technical lead. View online or download as PDF."},"hero":{"eyebrow":"Curriculum vitae","title":"My CV,","accent":"on one page.","intro":"The same content as the PDF — always up to date. Download it, print it, or just read it here."},"actions":{"download":"Download PDF","print":"Print"},"summary":"Full-stack engineer and technical lead with 10+ years of development experience building SaaS platforms, e-commerce, CRM systems and mobile apps. I own products end-to-end — architecture, backend (Laravel, NestJS), web (Next.js) and mobile (React Native) — and I specialise in the hard parts: multi-tenancy, offline sync, promotion and loyalty engines, and payment/ERP integrations.","highlights":["Co-led a multi-tenant POS SaaS: 181 data models, ~936 endpoints, 6 apps in ~4 months","Built promotion engines that always compute the customer's best price","Integrated 9+ payment providers, accounting/ERP sync and fiscal receipts","Shipped 5 React Native apps on a shared template (RN 0.81 → 0.86)","~7,100 commits across 19 production repositories; top contributor in 11","Introduced AI-assisted engineering workflows (agents, hooks, rulebooks)"],"experiencePoints":[["Lead architecture and delivery of SaaS, e-commerce and mobile products","Co-lead of a multi-tenant POS platform with offline branch hub and public APIs","Maintainer of 10 shared React/Next packages used across ~10 client sites","Set up AI-assisted workflows: planner/implementer/reviewer agents, quality hooks"],["Built backends, admin panels and storefronts with Laravel and Next.js","Delivered a paid-listing portal with payments, moderation and data reports","Rebuilt the studio website on the App Router with a hybrid CMS"],["Full-stack development of client websites and web applications"],["Built websites and web applications for clients, front end and back end"]],"projectsPick":["pos-saas","restaurant-ordering","pet-commerce-erp","gym-crm"],"languages":[{"name":"Armenian","level":"Native"},{"name":"Russian","level":"Fluent"},{"name":"English","level":"Professional"}],"labels":{"contact":"Contact","summary":"Summary","highlights":"Highlights","experience":"Experience","projects":"Selected projects","skills":"Skills","languages":"Languages","updated":"Updated"},"skillGroups":{"frontend":"Frontend","backend":"Backend & data","mobile":"Mobile & desktop","infra":"Infrastructure"}},"contact":{"meta":{"title":"Contact","description":"Tell me about your product, project or team. I usually reply within one working day."},"hero":{"eyebrow":"Contact","title":"Let's talk about","accent":"what you're building.","intro":"I work with founders, businesses and product teams who need an experienced engineer to build, improve or scale a software product — and I'm open to senior and lead roles. A few lines are enough to start; I read every message myself and usually reply within one working day."},"info":{"email":"Email","location":"Based in","response":"Response time","responseValue":"Within one working day","availability":"Availability","availabilityValue":"Open to selected projects and senior roles","copy":"Copy email","copied":"Copied!"},"form":{"title":"Send a message","name":"Your name","namePlaceholder":"Jane Smith","email":"Email","emailPlaceholder":"jane@company.com","company":"Company","companyPlaceholder":"Optional","topic":"What is it about?","budget":"Budget (optional)","message":"Message","messagePlaceholder":"What are you building, where are you now, and how can I help?","submit":"Send message","sending":"Sending…","privacy":"Your details are used only to reply to you.","topics":{"website":"Website","mobile-app":"Mobile app","platform":"SaaS / platform","consulting":"Audit / consulting","job":"Job opportunity","other":"Something else"},"budgets":{"lt-5k":"Under $5k","5k-15k":"$$5k – $15k","15k-50k":"$$15k – $50k","gt-50k":"$$50k+","unknown":"Not sure yet"},"errors":{"required":"This field is required.","tooShort":"This is a bit too short.","tooLong":"This is too long.","invalidEmail":"Please enter a valid email address."},"status":{"success":"Thank you — your message is on its way. I'll get back to you soon.","invalid":"Please check the highlighted fields.","rateLimited":"Too many messages in a short time. Please try again in a few minutes.","notConfigured":"The form isn't connected yet. Please email me directly.","sendFailed":"Something went wrong while sending. Please try again or email me directly."},"again":"Send another message"}},"learnPage":{"meta":{"title":"Learn","description":"Free lessons from 10+ years of building websites, apps and servers: from how the web works to Linux, e-commerce, DevOps and system architecture."},"hero":{"eyebrow":"Learn","title":"Everything I know,","accent":"explained simply.","intro":"From “what happens when you open a website” to multi-tenant SaaS architecture. Every lesson explains how it works, when to use it, the mistakes to avoid — and the questions people ask in interviews."},"search":"Search lessons…","all":"All","results":"lessons","empty":"Nothing found. Try another word.","startHere":"New here? Start with","categories":{"web":"Web basics","languages":"Languages","frontend":"Frontend","backend":"Backend","commerce":"E-commerce","data":"Data","mobile":"Mobile apps","linux":"Linux & servers","devops":"DevOps & cloud","architecture":"Architecture","security":"Security","ai":"AI","career":"Senior skills"},"levels":{"beginner":"Beginner","intermediate":"Intermediate","advanced":"Advanced"},"minutes":"min read","animated":"Animated","mine":"In my stack","worthKnowing":"Worth knowing","lesson":{"back":"All lessons","inShort":"In 30 seconds","contents":"On this page","why":"Why it matters","whyMine":"Why I use it","howItWorks":"How it works","whenToUse":"Use it when","whenNot":"Skip it when","alternatives":"Alternatives","bestPractices":"Best practices","mistakes":"Common mistakes","inMyWork":"In my real projects","qa":"Questions & answers","deepDive":"Deep dive","scenarios":"Real-world scenarios","problem":"Problem","solution":"How to solve it","cheatsheet":"Cheat sheet","glossary":"Glossary","qaAdvanced":"Senior-level questions","worthNote":"Not in my daily stack — I know the concepts and would learn the details when a project needs it.","related":"Keep learning","next":"Next lesson","prev":"Previous","copy":"Copy","copied":"Copied","caseStudy":"Case study","watch":"Watch it"},"player":{"play":"Play","pause":"Pause","replay":"Replay","step":"Step","title":"Animated explainer"}},"explainers":{"request":["You type example.com and press Enter. The browser gets to work.","First it asks DNS — the internet's phonebook — “what's the address of example.com?” and gets an IP back.","It opens a connection to that IP and does a TLS handshake, so everything after this is encrypted.","Now the real question: “GET /” — please send me the home page.","The server runs your code, which may ask the database for data.","The server answers “200 OK” with HTML. The browser draws the page. All of this in well under a second."],"dns":["The browser asks a resolver (often your provider's or 1.1.1.1): “where is example.com?”","The resolver asks a root server. Root says: “I don't know, but ask the .com servers.”","The .com servers say: “example.com's nameserver is ns1 — ask it.”","ns1 is the authoritative nameserver. It knows the real answer: 203.0.113.10.","The resolver remembers the answer for the TTL (here one hour) and hands it to the browser. Next time: instant."],"cloudflare":["Point your domain's nameservers to Cloudflare and it stands in front of your server. Your real IP stays hidden.","Visitors talk to Cloudflare first — it's a reverse proxy sitting in data centres all over the world.","Static files are cached close to the visitor: a cache HIT comes back in milliseconds and your server doesn't even notice.","Bots and floods hit the shield instead of your server. The WAF and DDoS protection throw them out.","With SSL mode “Full (strict)” both legs are encrypted: visitor ↔ Cloudflare and Cloudflare ↔ your server."],"http2":["HTTP/1.1: one connection carries one request at a time. Files wait in line like cars on a one-lane road.","If the first response is slow, everyone behind it waits. That's head-of-line blocking.","HTTP/2 sends many requests at once over a single connection, chopped into frames and mixed together.","HTTP/3 runs on QUIC over UDP: if one packet gets lost, only that stream waits — the others keep going."],"tls":["The browser wants to talk to example.com. A spy is listening on the café Wi-Fi. Classic.","The browser says “hello” and lists the encryption it supports.","The server sends its certificate. The browser checks it was signed by a trusted Certificate Authority.","They exchange key shares and both calculate the same secret key — without ever sending it.","Now everything is encrypted. The spy sees only gibberish and goes home sad."],"waiter":["An API is like a waiter. GET /menu — “bring me the menu” — 200 OK, here it is.","POST /orders creates something new: 201 Created.","PATCH /orders/7 changes part of an existing order: 200 OK.","DELETE /orders/7 removes it: 204 No Content — done, nothing to show.","GET /orders/99 asks for something that doesn't exist: 404 Not Found.","No token, no service: 401 Unauthorized. The waiter wants to know who you are."],"websocket":["Polling: the app keeps asking “anything new?” — “no” — “anything new?” — “no”… The server gets very tired.","WebSocket: one HTTP request “upgrades” the connection (101 Switching Protocols) and keeps the line open.","Now the server can push messages the moment something happens. Ding!","Rooms: everyone watching order #42 joins one room, and one message reaches them all."],"queue":["The user places an order. The API answers instantly with “202 Accepted” and puts the slow jobs on a queue.","Workers take jobs from the queue one by one: send the email, build the PDF, sync with accounting.","A job fails? No panic — it goes back to the queue and is retried later, with backoff.","Busy day? Start more workers and the queue empties faster. The user never waited for any of it."],"fail2ban":["A server with SSH open. A hacker arrives with a list of passwords. fail2ban is on duty (a bit sleepy).","First guess: wrong password, 401. fail2ban reads the log and makes a note.","Again… and again… fail2ban keeps counting the failures from this IP address.","Fifth failure inside the time window. That's the limit (maxretry). fail2ban wakes up.","Bang! fail2ban adds a firewall rule and the IP is banned for an hour. Bye!","A real user with an SSH key walks straight in. Bans only hit the attackers."],"docker":["“It works on my machine!” — but the server has a different PHP version, and everything breaks.","A Dockerfile describes the exact environment. Building it produces an image.","Run that image anywhere and you get identical containers — on your laptop and on the server.","Docker Compose starts the whole app — code, database, Redis — with one command."],"kubernetes":["Kubernetes is the captain. You tell it what you want — “3 copies of my app” — and it makes it so.","A container crashes? The captain notices and starts a fresh one. Self-healing.","Traffic spikes? It adds more copies automatically, then removes them when things calm down.","New version? It replaces containers one by one, so the app never goes down."],"microservices":["A monolith is one big app that does everything: orders, users, payments. Simple to build and run.","A modular monolith keeps one app but with strict internal borders. Most teams should start here.","Microservices split it into small apps that talk over the network. Teams can deploy them independently…","…but now the network can fail. One service is down and the others wait for timeouts. Complexity is the price."],"kafka":["Producers publish events — “order created” — to a topic. Kafka appends them to a log, in order.","A topic is split into partitions, so many events can be written and read in parallel.","Each consumer group reads at its own speed and remembers its position: the offset.","A consumer was offline? It comes back and continues from its offset. Nothing is lost."],"load-balancer":["One server, a lot of users. CPU at 100%, everyone waits. Not great.","A load balancer spreads the requests across several servers.","Health checks: if a server is sick, the load balancer stops sending it traffic until it recovers.","Keep the servers stateless — sessions live in Redis — so any server can handle any user."],"cache":["No cache: every request goes to the database. 120 milliseconds, every time.","After the first read, the app saves the result in Redis with a TTL — say, 60 seconds.","The next request finds it in the cache: a HIT, about 2 milliseconds.","The product changes? Delete the cache key. The next request misses, reads fresh data and fills the cache again."],"tenants":["Multi-tenant SaaS: many customers (tenants) live in one platform and one database, each with their own data.","Every request carries the tenant's identity, and every query is scoped to that tenant.","Café A tries to read Café B's data? It hits a wall: 404, as if it doesn't exist.","One tenant flooding the system? Rate limits keep the noisy neighbour from slowing everyone else down."],"payment":["The customer checks out. The shop creates the order with status “pending”.","The customer pays on the bank's secure page and confirms with 3-D Secure on their phone.","The bank calls the shop back with a signed webhook: “paid”. The order becomes paid.","The same webhook arrives twice? The idempotency check says “already done” — nobody is charged twice.","Every night a reconciliation job compares the shop's ledger with the bank's report. They match."],"git":["main is the branch that's always ready to ship. Each dot is a commit.","New feature? Create a branch and commit your work there, without touching main.","Open a pull request: a teammate reviews it and CI runs the tests and the linter automatically.","Approved and green? Merge into main, and the pipeline deploys it to production."],"rag":["A user asks: “What's our refund policy?” A bare LLM has never seen your docs, so it confidently guesses. 90 days? Nope.","Earlier, your documents were cut into small chunks, and each chunk was embedded (turned into a vector of numbers) and stored in a vector DB.","The question is embedded too. The retriever finds the top-k chunks whose vectors sit closest to it. Here: §2 and §4.","Those chunks and the question go into the prompt together: “Answer using only this context.”","Now the LLM answers from real text and cites its source: 30 days, see §2. No more making things up."],"agent":["An AI agent gets a goal, not a script: “find me a cheap flight”.","First it plans: break the goal into steps. Search, pick, pay.","Then it acts: it calls a tool — web search, running code or some API — instead of just talking.","It observes the result, decides what's next, and goes around the loop again. Plan → act → observe → decide.","Paying is risky, so the agent stops and asks a human. You click approve. (Or don't.)","The goal is reached, so the loop ends. Done — and nobody was charged by surprise."],"oauth":["You click “Sign in with ID” on app.com. The app never wants to see your password — that's the whole point of OAuth.","The app makes a secret code_verifier and keeps it. It redirects you to the identity provider with only its hash: the PKCE code_challenge.","On the provider's page you log in and consent: “Yes, app.com may see my name and email.”","The provider sends you back to the app with a short-lived, one-time code. Alone it's useless — the app passes it to its backend.","The backend swaps the code plus the verifier for tokens. The provider checks the verifier against the challenge. The ID token (OIDC) says who you are: Ani.","The access token goes with every API call. The API checks it, the lock opens: 200 OK."],"pipeline":["A developer pushes code. The CI/CD pipeline wakes up, and the linter checks the style first. Green.","Next, the tests run… and one fails. Red! Better here than in front of users.","The developer fixes it and pushes again. Same pipeline, same tests: all green now.","CI builds a Docker image, app:1.4, and deploys it to staging, a copy of production for a final look.","Production is serious business, so a human clicks “approve” first.","The same image goes to production: v1.4 is live. Something wrong? The rollback button brings back v1.3 in seconds."],"backup":["Every night at 02:00, while everyone sleeps, the database makes a backup and sends a copy to the NAS.","The 3-2-1 rule: 3 copies of the data, on 2 different kinds of storage, with 1 copy off-site, far away in the cloud.","Disaster! The server catches fire, or someone runs DROP TABLE users on production. It happens to everyone eventually.","No panic: take the off-site copy and restore it. The database is back, missing only a few hours of data.","A backup you never restored is just a hope. So restore test regularly into a scratch DB and check that the data is really there."],"ssr":["CSR: the server sends an almost empty HTML shell and a big JavaScript bundle. The browser shows a spinner and gets to work.","The JS runs, fetches data from the API and only then draws the page. The user spent all that time admiring the spinner.","SSR / SSG: the HTML is rendered on the server (or at build time). The browser paints real content right away — fast and SEO-friendly.","Looks ready, but the button does nothing yet. Then the JS arrives and hydration attaches event handlers to the existing HTML — now it clicks.","ISR: the ready page is served straight from the cache. After the revalidate time, Next.js rebuilds it in the background and swaps in the fresh version."],"react-state":["A React app is a tree of components: App on top, Header and Cart below, each with children of their own.","Data flows down as props: a parent hands values to its children. Children can read props, but never change them.","The user clicks “+” in Item. Item can't change the count itself, so it calls a function Cart passed down — the event flows up.","Cart calls setCount(2). React re-renders Cart and everything below it — only that subtree. App, Header and Logo keep napping.","The new value flows down as props. React compares the new result with the old one and updates only what actually changed in the DOM."],"db-index":["The query: find the user with id = 42. There's no index, so the database reads the table row by row. Already sweating.","It found 42… but has to keep going — maybe there's another one further down. A full Seq Scan over a million rows: slow.","CREATE INDEX: the database builds a B-tree — a sorted map of values that points to where each row lives.","Now it just jumps: 42 is less than 50 → go left, more than 25 → go right, and there's the row. A few hops instead of a million rows.","EXPLAIN confirms it: Index Scan. Milliseconds instead of seconds — the database is visibly relaxed.","But every index must be updated on each INSERT and UPDATE. Index every column and writes get slow. Index what you actually search by."],"injection":["A login form. Instead of a name, the hacker types ' OR 1=1 -- and smiles behind the sunglasses.","The unsafe code just glues the input into the SQL string. The quote closes the string, OR 1=1 is always true, and -- comments out the password check.","The database obediently runs exactly that: “all users where … or true”. The hacker logs in as the first user — often admin. Oops.","Fix: a parameterized query. SQL and data travel separately, so the input is just a weird name. No such user — 401.","Bonus layers: validate input and put a WAF in front. It recognises typical attack patterns and blocks them before they reach the app."],"serverless":["No requests — zero instances. Nothing is running and you pay nothing. The platform is fast asleep.","The first request arrives. A fresh instance has to boot: load the code, start the runtime. That's a cold start — a yawn of a few hundred milliseconds.","A traffic burst? The platform simply clones more instances, and each one handles its own requests in parallel. No servers to set up.","Traffic drops. Idle instances are stopped after a while — back to zero. Nobody sits around waiting on your dime.","You pay per invocation and execution time, not for idle hours. Perfect for spiky traffic — just remember the cold starts."],"shell-pipes":["cat — played here by an actual cat — pours access.log into the pipe. Each | hands one command's output to the next as input.","grep 500 keeps only the lines that contain 500. The happy 200s and the lost favicon fall off the line.","awk '{print $7}' cuts each line down to the 7th field: the path. Then sort puts identical paths next to each other.","uniq -c folds neighbouring duplicates into one line with a count. That's why sort goes first: uniq only sees neighbours.","sort -rn sorts by number, biggest first. The noisiest error is on top: /pay. Of course it's the payment page."],"permissions":["ls -l shows the file's door plate: -rw-r-----. Owner alice can read and write, group devs can only read, everyone else gets nothing.","Bob is neither the owner nor in devs, so he's “others”: ---. cat secret.txt → Permission denied. The door doesn't even creak.","Bob is in the sudo group, so sudo gives him a temporary root pass. Root walks through any door — and the command gets logged.","Now the SSH key: -rw-r--r-- (644), anyone can read it. ssh refuses to use it: permissions too open. Picky, but right.","chmod 600: read and write for the owner, nothing for group and others. The key is locked, ssh is happy. Private keys and .env live like this."],"systemd":["03:13. myapp runs as a systemd service; the unit file says Restart=on-failure, RestartSec=5. systemd, PID 1, sips its tea.","03:14: crash! The process exits with status 1. The developer is asleep and has no idea. Nobody panics… yet.","systemd doesn't panic either: it waits 5 seconds and starts a fresh process. New PID, same app, and the site is back up.","In the morning journalctl -u myapp tells the whole story: what crashed, when, and that systemd restarted it.","sudo reboot. The service is enabled (WantedBy=multi-user.target), so systemd starts it at boot by itself. Nobody has to log in."],"disk-logs":["The app writes logs. And writes. And writes. Nobody rotates them, and the disk creeps from 60% to 100%.","100%: every write fails with “No space left on device”. Uploads, sessions, even the database start breaking. The server panics.","df -h shows which filesystem is full. du -sh … | sort -h points at the culprit: one 14 GB app.log. Of course.","logrotate renames the log, compresses old copies to .gz and keeps only 7. The disk drops to 38% and the server breathes again.","While you're here: sudo apt update && sudo apt upgrade installs the security patches. Better yet, let unattended-upgrades do it daily."],"nginx-stack":["The browser sends GET /logo.png over HTTPS (:443). nginx, the receptionist, terminates TLS right here, so the apps behind it don't have to.","A static file? nginx grabs it from disk itself (try_files) and hands it back in milliseconds. No app was bothered.","GET /checkout.php goes to PHP-FPM via fastcgi_pass. The PHP workers run the code and send the page back through nginx.","GET /api/cart goes to a Node app with proxy_pass to a local port like 127.0.0.1:3000. nginx just passes the answer back.","On the way back nginx gzips the response and adds cache headers. The response goes on a diet, and the browser can reuse files next time."],"cloud":["One VPS: cheap and simple, but you're also the admin, the backup guy and the 3 a.m. alarm clock.","The cloud hands you building blocks: VMs, a managed database, object storage and a CDN — in a region split into zones.","Zone a goes down. Your app also runs in zone b, so traffic simply moves over. Users don't notice a thing.","Someone forgot a huge VM running, idle. The cloud bills for every hour it runs, so the bill monster grows all night.","A budget alert pings your phone, the forgotten VM gets shut down and the monster shrinks. Set alerts on day one."],"iac":["Infrastructure as code: you describe the servers and the database you want in a file — main.tf — and keep it in Git.","terraform plan compares the code with reality and shows the diff: 2 to add, 1 to change, 0 to destroy. Nothing happens yet.","terraform apply makes it real through the cloud's API: two servers appear and the database gets bigger.","Someone resized web-2 by hand in the console. The next plan spots the drift, and apply puts it back to match the code.","Terraform builds the servers; Ansible sets up what runs inside them. One playbook configures every server the same way.","Run the playbook again: changed=0. Ansible is idempotent — it only changes what isn't already in the desired state."],"observability":["Checkout takes 8 seconds and users are fuming. Time to call the detectives: metrics, traces and logs.","Metrics say THAT something is wrong, and since when: p95 latency jumped to 8 s and errors went from 0.1% to 4%.","A trace follows one request through every service. The waterfall points straight at the culprit: payment takes 8.1 of 8.3 s.","Logs say WHAT happened. Filter by the same trace id and there it is: the bank API timed out.","Sentry catches the exception with its stack trace — file and line — and groups it: 312 events, 89 users, release v1.4.","Every failed checkout burns the SLO's error budget. It's burning way too fast, so an alert pages the on-call engineer."],"secrets":["A developer hard-codes the database password in .env and pushes it to a public repo. What could possibly go wrong?","A bot scanning GitHub finds it within minutes. The hacker says thanks and walks straight into the database.","Fix: no secrets in the code. The app proves its identity to a vault and gets its own database login that expires in an hour.","Rotation: when the lease runs out, the old login is revoked and a fresh one arrives. No deploy, no downtime.","Every access is written to the audit log. And that leaked hunter2? Long rotated, so the hacker gets “denied”."],"mvc":["A request arrives: POST /orders. The router reads the URL and method and picks the controller action that will handle it.","Middleware runs first. The auth guard checks the token: no token, no entry (401). This one is fine, come in.","Validation fails: qty is -3. The request bounces back with 422 and field errors before any business logic runs.","A valid request: the thin controller hands off to a service with the business rules, and the model saves the order to the DB.","The answer climbs back up: 201 Created with JSON (or a rendered view). Each layer did one job, so each is easy to test and change."],"typescript":["A function with types: price must be a number. The type checker (tsc) is on duty with its magnifying glass.","Someone passes the string \"15\". Red squiggle! TypeScript catches it at build time, before a single user sees it.","Without types, plain JavaScript runs it happily: \"15\" + 5 = \"155\". The bug shows up in production. At 3 a.m., of course.","Fix the call to addFee(15) and tsc reports 0 errors. The fee is 20, as intended, and everyone gets some sleep.","Bonus: types power autocomplete. Type order. and the editor already knows the fields and their types."],"graphql":["REST: the app needs a user, their posts and the comments. That's three endpoints and three round trips, one after another.","And each response sends everything it has. The screen needed a name and a title; it got 48 KB. That's over-fetching.","GraphQL: one request to /graphql with a query listing exactly the fields you want. The answer has the same shape. Tiny.","The trap: fetch 50 posts, then each post's resolver asks the DB for its author separately. 1 + N = 51 queries. The DB is not amused.","DataLoader collects all those ids and sends one batched query: WHERE id IN (…). 2 queries instead of 51, same answer."],"saga":["The order service saves order #7 and an \"OrderCreated\" row in the outbox table, in one local transaction. Both or neither.","After the commit, a relay publishes the outbox row to the event bus. The stock service reserves 2 items.","Next, payment tries to charge $30… card declined. There is no shared transaction across services to roll back.","So the saga runs a compensating action: \"PaymentFailed\" tells stock to release the 2 items it reserved.","Finally the order is marked CANCELLED. Nobody was charged, no stock is stuck, and every service agrees again."],"search-index":["A search engine keeps an inverted index: like the index at the back of a book, every word points to the documents that contain it.","The user types \"iphnoe\". An exact lookup finds nothing, but fuzzy matching forgives a typo or two and lands on \"iphone\".","Ranking: every match gets a relevance score. \"iPhone 15\" beats the case and goes on top; the Galaxy doesn't match at all.","Facets are filters with counts over the current results: Apple (2), $500+ (1). One click and only the phone is left.","The price changes in the database. An event goes on a queue, a worker updates the index, and search shows $899 moments later."],"html-css-js":["HTML is the structure: walls, a roof, a door and windows. It says what things are, not how they look.","CSS is the paint and the layout. Colours go on, and Flexbox finally lines up those wonky windows.","JavaScript is the electricity: addEventListener('click') wires the button to the lamp. Click — and there was light.","To draw it, the browser parses HTML into the DOM and CSS into the CSSOM, combines them into a render tree, then does layout and paint.","Bonus: a

with a click handler is a painted door — the keyboard can't get in. A real

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