Danilo Popovikj

One engineer.
The whole system.

Nine years of building production systems end to end: APIs and the services behind them, background pipelines, frontends people enjoy using, and the Kubernetes clusters it all runs on. I design for simplicity, because simple systems ship faster, fail less, and are easier to change when the product inevitably does. And for the past seven years, I have been the one on call when something breaks.

Danilo Popovikj

9+ yrs

of production systems

years shipping software
9+
products in production
10+
product built from scratch to acquisition, solo
1
exit of a product I helped build
$42M

Vetted by

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Selected work

Products built from zero

Each of these is live, with users or store releases. I designed, built, and shipped them end to end. Tap a card to see how.

AI · Document intelligence

Quist AI

Built solo as Forty Years AI, acquired by Quist in 2026.

An AI document-intelligence SaaS: users upload raw source documents, async AI pipelines turn them into structured draft reports, and teams refine the output in a collaborative editor. I built it end to end, alone, under its original name Forty Years AI. Quist acquired it in 2026, and I still maintain it.

  • Built the entire platform: FastAPI and PostgreSQL with SQLModel, Celery and Redis async AI pipelines, React with TypeScript, TanStack Router and Query.
  • Claude-powered pipelines extract structured data from uploaded documents and generate draft report content for humans to refine.
  • Custom rich-text editor (Lexical) with inline comments and version history.
  • Alembic migrations, pytest with coverage, and Playwright end-to-end tests on every change.
  • Multi-tenant from day one: tenant-scoped JWT auth with data isolation at the query layer.
  • Production infra as code: Terraform on DigitalOcean, Docker, Traefik with automatic TLS, daily database backups, and full observability with OpenTelemetry, Prometheus, Grafana, and Loki.
Visit Quist AI
FastAPIPostgreSQLCeleryRedisClaude AIReactTypeScriptLexicalDockerTerraformOpenTelemetry

Fintech · Consumer app

Abundant Living

A personal finance app on web, iOS, and Android, all from one codebase.

A full personal finance platform with income tracking, envelopes, reports, and multi-currency support. Shipped as a PWA and as native mobile apps from a single Next.js codebase.

  • Built it solo: Next.js, Chakra UI, Prisma and PostgreSQL, wrapped with Capacitor for the iOS and Android store releases.
  • Envelope budgeting, transactions, recurring income, and monthly assignment reports with charts.
  • Internationalization, offline-friendly PWA behavior, Apple and Google sign-in, and app store deployment pipelines.
Visit Abundant Living
Next.jsTypeScriptChakra UIPrismaPostgreSQLCapacitor

Startup · Founder

Owl View

My own startup, from first commit to the decision to wind it down.

An AI-powered data analyst for online stores, giving plain-language insights from GA4. From idea to v1, first customers, a small team, v2, and accelerator rooms in nine months.

  • Owned the full lifecycle: product, engineering, hiring, sales, and eventually the decision to wind it down with clear eyes.
  • Built the entire platform myself while running the company: GA4 integration, AI insight generation, visual page inspection.
Next.jsTypeScriptPostgreSQLGA4 APILLMs

Hospitality · Web

Damari Skiathos

A luxury villa brand online, with bookings and an AI content engine.

The complete web presence for luxury villas in Skiathos, Greece. High-end design, a direct booking funnel, and an automated AI-powered SEO machine.

  • Designed and built the full site: filterable galleries, property pages aimed at different types of guests, location guides, and direct booking.
  • Automated AI blog pipeline (Claude) that publishes SEO-optimized articles daily. Over 60 posts so far, targeting high-intent travel keywords.
  • An internal Social Media Studio that generates Instagram carousels from blog posts and web-researched briefs.
  • Four languages with locale routing, plus lead-magnet funnels with automated email delivery.
Visit Damari Skiathos
Next.jsTypeScriptTailwind CSSMDXClaude AIi18nSEO

AI · SaaS

DINNA AI

The frontend of an AI marketing platform, as founding frontend engineer.

An AI CMO that runs social media marketing across 12+ channels. I owned the frontend: the architecture, the design system, and the delivery rhythm, with a tiny team around me.

  • Chose the stack and set up the frontend architecture and component system from scratch.
  • Shipped the MVP, then the iterations that reached the first paying customers.
Visit DINNA AI
ReactNext.jsTypeScript

How I help

Two audiences, one engineer

Whether you're a founder with an idea or an engineer checking my work, here's what working with me looks like.

  1. I've done this before

    I founded my own startup, led an AI product to its first paying customers, and built several products from scratch on my own, one of them all the way through to acquisition. The road from an idea to a working product in real hands is familiar ground to me.

  2. It starts with understanding

    Before anything gets built, I sit down with you to understand your product, your users, and what you actually need. You explain it once, to the person who will build it, and we shape the plan together.

  3. Your app, in one pair of hands

    Backend, frontend, mobile, infrastructure, releases. I own the application end to end and keep it running in production. When you need something, you message me directly, and changes turn around fast.

  4. Simple, on purpose

    The cheapest feature is the one we agree not to build. I push for the simplest system that does the job, because that is the one that ships quickly and doesn't fight you later.

The short version
I've been the founder, so I build like one. Tell me what you're building, and I'll help you get it out the door.

Experience

Nine years, every layer of the stack

Startups, scaleups, and one company of my own. Tap any role for the details.

  1. Detect Auto logo

    Detect Auto

    Automotive AI

    Senior Software Engineer

    Jun 2025 - Present · United States · Remote

    AI and computer vision that audits repair orders and automates auto-shop service workflows.

    • Work across the whole platform: FastAPI backend, React frontends, a browser extension, and the React Native mobile app, all running on Kubernetes (K3s).
    • Build the AI features, like vehicle inspection findings and maintenance predictions, with model outputs processed in background pipelines before they reach the shop.
    • Build mobile features in React Native: offline-first sync with ElectricSQL, camera and voice capture, and Play Store releases through CI.
    • Manage the release cycle: GitHub Actions pipelines that test, build, and deploy to Kubernetes, plus the mobile and extension store releases. I'm on call when production breaks.
    • Improve developer workflows: local k3d clusters that mirror production, hot reload with DevSpace, one-command Makefile setups.
    • Integrate AI into our engineering practices: shared code standards injected into AI coding assistants, and agent-driven workflows the whole team uses.
    • Run the deep-dive technical interviews for engineering candidates.
    PythonFastAPITypeScriptReactReact NativeKubernetesTerraformPostgreSQLCeleryOpenTelemetryGitHub ActionsOpenAIGeminidetectauto.com
  2. Quist logo

    Quist

    AI · Document intelligence

    Software Engineer · Part-time

    Apr 2025 - Present · Remote

    AI-powered document intelligence. Started as Forty Years AI, acquired by Quist in 2026.

    • The product was developed end to end by me alone, under its original name Forty Years AI: FastAPI and PostgreSQL, Celery and Redis background AI pipelines, a React frontend with a custom collaborative editor, and Terraform-managed infrastructure.
    • Claude-powered pipelines extract structured data from uploaded documents and generate draft report content for humans to refine.
    • Quist acquired the product in 2026 and kept me on as the engineer behind it. These days I maintain and extend it part-time.
    PythonFastAPIPostgreSQLCeleryRedisClaude AIReactTypeScriptTerraformDockerquistvaluation.com
  3. DINNA AI logo

    DINNA AI

    AI marketing

    Frontend Lead

    Feb 2025 - Aug 2025 · Remote

    An AI CMO that runs social media marketing end to end across 12+ channels.

    • Led the frontend of an AI marketing platform from an idea, to MVP, to the first paid SaaS version.
    • Owned the architecture, the UI system, and the delivery pace as the founding frontend engineer.
    ReactTypeScriptNext.jsdinna.ai
  4. Owl View logo

    Owl View

    E-commerce AI analytics

    Founder · CEO · Engineer

    Jan 2025 - Aug 2025 · Tallinn, Estonia

    AI-powered data analyst for online stores. Plain-language insights from Google Analytics 4.

    • Quit my full-time engineering career to pursue an idea. In 9 months we went from an idea, to v1, first few customers, hired a designer and a sales person, built v2, and went through startup accelerators.
    • Built the whole product myself: GA4 integration, AI-generated insights and action items, visual inspection of product pages.
    • Led both the business and the technical sides. When it became clear the space demanded a different type of company, we made the tough call to let it go. I learned firsthand what founders weigh when they decide what to build next.
    Next.jsTypeScriptPostgreSQLGA4 APILLMs
  5. PrettyDamnQuick logo

    PrettyDamnQuick

    E-commerce / Shopify

    Full Stack Software Engineer

    Sep 2023 - Dec 2024 · Remote

    Checkout and delivery optimization platform for Shopify brands.

    • Built an end-to-end A/B testing feature with a backend-for-frontend microservice and a rule engine, so merchants could set dynamic rules for showing shipping methods (for example, only when cart value is over $50).
    • Designed a Redis-backed traffic distribution algorithm that classifies requests into variants for precise A/B splits and controlled feature releases.
    • Built a Shopify checkout customization tool where merchants create different versions of their checkout and see which one converts best.
    • Built a Python data pipeline that pulls together warehouse and shipping carrier data for clearer package tracking.
    • Took my turn in the on-call cycle, fixing critical production issues weekly.
    TypeScriptNode.jsReactRedisPythonShopifyMicroservicesprettydamnquick.com
  6. funda logo

    funda

    Real estate platform

    Back End Software Engineer

    Oct 2022 - Aug 2023 · Amsterdam, Netherlands

    The Netherlands' largest real estate platform.

    • Architected a user inactivity detection system together with the front-end and data teams. It classifies users and automatically deletes inactive accounts after warning emails.
    • Was the only back-end engineer on my feature team, so I owned all the back-end microservices and the cross-team coordination.
    • Owned the back-end side of cross-team designs, working with Staff and Lead engineers to fit our services into the platform-wide architecture.
    .NETC#MicroservicesAzurefunda.nl
  7. InoVirtue logo

    InoVirtue

    Coaching & wellbeing tech

    Senior Software Engineer

    Aug 2021 - Oct 2022 · Munich, Germany · Remote

    Munich venture studio building platforms for coaches and service providers.

    • Built a mental health social app: profiles, scheduling, video calls with coaches, and billing by the minute.
    • Created and owned the authentication system on Azure AD B2C with Custom Policies. AD B2C is very limited in how you can customize its UI, so I engineered a custom, unit-testable TypeScript UI framework around it.
    • Ran technical interviews for new hires and reported my assessments directly to the CTO.
    TypeScriptAzure AD B2CReact.NETinovirtue.com
  8. GrocerKey logo

    GrocerKey

    Grocery e-commerce

    Software Engineer

    Dec 2020 - Aug 2021 · Tel Aviv · Remote

    White-label grocery e-commerce for US supermarket chains, later acquired for $42M.

    • Moved parts of a monolith backend into separate microservices: migrating the data, then releasing tenant by tenant behind feature flags so nothing broke.
    • Built and delivered an impression and click counting service with AWS Redshift warehousing and Apache Kafka.
    • Moved payments out of the monolith into its own service supporting multiple payment providers, with a smooth migration using feature flags and A/B testing.
    C#.NETKafkaAWS RedshiftMicroservices
  9. IT Labs logo

    IT Labs

    Software consultancy

    Software Engineer

    Jul 2017 - Dec 2020 · Skopje, North Macedonia

    LA-founded consultancy with 150+ engineers and a major hub in Skopje.

    • Built a paper filing system for the government of Florida on a fixed nine-month deadline ahead of the elections. The deadline could not move, so we cut scope deliberately and shipped on time.
    • Worked full-stack with a US-based team with very little timezone overlap, so I learned to plan and execute on my own. That got me picked for the critical election project after a year and a half.
    • Started as a three-month summer intern, got a full-time offer, and juggled university and full-time work for three years.
    .NETC#AngularSQL Serverit-labs.com

Faculty of Computer Science and Engineering, Skopje (FINKI)

Bachelor's degree, Computer Science

2015 - 2020

Recommendations

From the people I've built with

Founders and engineers I've worked with, in their own words. All of these are on my LinkedIn.

“I've been in software for 20+ years and Danilo is hands-down the best engineer I've worked with. He is a problem-solver first and foremost: he doesn't just do what you ask like most engineers — he thinks through what you're trying to accomplish and finds the ideal solution. He is someone to whom you can present a problem with the confidence that he will solve it at the root cause. He is also well-rounded enough to think about the user experience and make sure whatever he builds is easy to use. Lastly, he's just a nice guy and fun to talk to. When my product was acquired, he immediately won the trust of the new team as easily as he won my own trust when I first met him.”

Dave Prager

Founder · Forty Years AI & Inner Pitch

Hired Danilo to build his product · May 2026

“I wholeheartedly recommend Danilo as a Front-end Lead or a Back-end Lead. He is a rare talent to come across, bringing with him a diverse background of expertise. His exceptional work ethic, creative eye for design, and ability to seamlessly blend his backend experience into frontend execution make him an invaluable asset. Danilo works brilliantly with the team, always brings contagious enthusiasm, and consistently takes initiative to push the product forward. His dedication to the products he develops is evident in everything he does.”

Ina Markovik

Founder & Architect of DINNA AI

Managed Danilo directly · May 2025

“I had the pleasure of working with Danilo in funda. Danilo is smart, an excellent communicator and highly motivated software engineer. In his role Danilo was responsible for developing new features across greenfield and legacy systems. Danilo did a fantastic job balancing the business requirements (delivering new features) and the technical stability (thinking ahead and reducing technical debt). He gets stuff done, but he also knows when to slow down and think about the long term maintainability of the system. I've also come to know Danilo as a great person, his enthusiasm is inspiring as I think his team members would attest! 10/10 would recommend!”

Stephan Hoekstra

Agile coach & software craftsman · funda

Managed Danilo directly · May 2023

“I was lucky to have Danilo working on our team recently, and I was impressed by his expertise and practical approach to problem-solving, making him an invaluable asset to any organization. Danilo's ability to balance the demands of developing new features while helping reducing our tech debt went really smooth. I can also confidently say that he is a great colleague, full of enthusiasm and passion for his work. I highly recommend Danilo without reservation, working with him was a helpful and enjoyable experience.”

Ariadine Gomes

Senior Software Engineer · funda

Worked with Danilo on the same team · July 2023

Toolbox

The stack I ship with

Everything here has shipped to production on something I built. The core I reach for most: TypeScript, Python, React, FastAPI, PostgreSQL, and Kubernetes.

TypeScriptPythonC# / .NETReactNext.jsReact NativeFastAPINode.jsCeleryPostgreSQLRedisSQLModelPrismaAlembicApache KafkaDockerKubernetesTerraformGitHub ActionsAWSAzureDigitalOceanVercelTraefikCapacitorChakra UITailwind CSSViteTanStackLexicalClaudeOpenAIGeminiOpenTelemetryPrometheus / GrafanaLokiAlertingOn-callMicroservicesFeature flagsA/B testingCI/CDPlaywrightpytest