Sr. Web Developer · SaaS Specialist · AI Enthusiast

Building scalable software that grows with your business

I help SaaS companies build and scale web products end-to-end — from launching MVPs and adding new features to modernizing products that become harder to maintain as they grow.

Worked with

Paayed
Inditex
FinQuery
Symphony
Devtech
Nulia
Fitcher
Paayed
Inditex
FinQuery
Symphony
Devtech
Nulia
Fitcher

The Person Behind the Code

Get to Know Me

Petar Jovanovic

7+

Years of experience

3

Startups built from ground up

10+

Production projects

100K+

Users impacted

Hi there! I'm Petar, a Senior Software Engineer and technical partner. I'm here to help you build or evolve your SaaS product end-to-end — one that solves the right problem, feels effortless to use, and can grow from user #1 to user #1,000,000.

I've spent the last 7+ years building products across startups and large enterprise environments, including platforms for Fortune Global 500 companies, spanning fintech, ed-tech, social networking, and e-commerce.

That experience has taught me that the best software comes from understanding the problem before writing the solution. Before thinking about implementation, I want to understand the problem we're actually trying to solve. Who is using the product? Why do they need this feature? Is there a simpler way to achieve the same outcome? And will the decisions we make today still make sense as the product grows?

That's the mindset I bring to every project.

I especially enjoy the challenges that come with growing SaaS products. What starts as a simple application naturally becomes more complex as customers, features, and requirements accumulate. Patterns that worked at the beginning stop scaling. Development slows down. Small changes start affecting unexpected parts of the product.

I enjoy stepping into that complexity, understanding what's causing it, and finding ways to make the product easier to build, maintain, and evolve.

That mindset shaped some of the work I'm most proud of. Most recently, at Paayed, a UK-based B2B fintech SaaS platform, I saw that an inconsistent UI and duplicated frontend patterns were becoming increasingly difficult to maintain as the platform grew. I built a shared component library and design system that was adopted across the product, giving the team a stronger foundation for developing new features and evolving the platform.

I'm also someone who cares about the small details. Whether it's an interaction that doesn't quite feel right, an unnecessarily complicated piece of code, or an architectural decision that could create problems later, I find it difficult to simply say, "good enough." I want to finish something and genuinely be proud of what I've built.

AI has made building software faster than ever, and I use it extensively in my own development process. But I think that makes engineering judgment even more important. The interesting question is increasingly not "Can we build this?" but "Should we build this — and what's the simplest way to solve the actual problem?"

Outside of client and product work, I'm building What Is The Output, my own experiment in making developer education more personalized. Building something of my own has given me another perspective on software — thinking not only about architecture and code, but also about users, validation, priorities, and whether an idea actually creates enough value to deserve being built.

And when I'm away from the keyboard, you'll usually find me playing music, reading, or spending time with my family.

So if you're building a SaaS product and looking for an engineer who will understand the bigger picture, care about the details, contribute ideas, and take ownership beyond the code itself — we'll probably have a lot to talk about.

My values

Meticulous

Whether it's an interaction that doesn't feel right, an overly complicated piece of code, or an architectural decision that could cause problems later — I find it difficult to simply say 'good enough.' I want to finish something and genuinely be proud of what I've built.

Transparent

I surface concerns early rather than staying quiet and letting them grow. I value clear, honest communication — about what's working, what isn't, and what decisions we're making and why.

Problem-first

Before thinking about implementation, I want to understand the actual problem. Who is using this? Why do they need it? Is there a simpler way? The question is no longer 'Can we build this?' — it's 'Should we, and what's the simplest way to solve the real problem?'

Purposeful

I understand the bigger picture, contribute ideas, and take ownership beyond the code. I'm not completing a task list — I'm helping build a product that solves the right problem and can grow from user #1 to user #1,000,000.

Process

How we'll work together

01

Step 01

Analyze Your Requirements

Every successful product starts with understanding the problem. We don't start building until I fully understand every detail of your vision. I'll take the time to learn about your business, users, goals, and technical constraints before making any implementation decisions. The right solution begins with asking the right questions.

02

Step 02

Propose the Right Solution

Once I understand the bigger picture, I'll recommend an approach that balances business goals, technical quality, scalability, and development speed. Every decision is made with your product's long-term success in mind.

03

Step 03

Build with Engineering in Mind

This is where ideas become reality. I leverage AI to accelerate development, helping you validate your idea faster without compromising quality. Combined with clean architecture, maintainable code, thoughtful user experiences, and transparent communication, it allows us to move quickly while building software that's made to last.

04

Step 04

Launch & Keep Improving

Shipping isn't the finish line—it's the beginning. After launch, we'll gather feedback, measure results, iterate on what matters, and continue improving the product as it grows.

Selected Work

What I've built

Fintech · Startup · Accounting & Analytics

Paayed - All in One Payment Platform (Accounting, CRM, Payments)

Led the development of a shared npm UI component library and design system, establishing scalable frontend standards that improved UI consistency, accelerated development, and reduced maintenance costs. Delivered core fintech features including secure authentication, 3DS payment flows, Hosted Payment Pages, analytics, CRM, reporting, and accounting modules.

TypeScriptReactNext.jsTailwindRadix UIJestDockerAWS
  • Shared UI library adopted company-wide
  • 90+ legacy components standardized & moved to library
  • Accelerated feature delivery
  • Reduced long-term maintenance
  • UK fintech compliance requirements

Fashion Industry · Enterprise · E-commerce · EdTech

Symphony - Software Development Company

4 client projects · Sep 2022–Dec 2024

  • Fortune Global 500 MFE PlatformShipped Micro-Frontend (MFE) web app supporting the article production workflow and day-to-day business operations between external suppliers worldwide and the company’s quality assurance teams. Built a shared npm UI library adopted across 5+ engineering teams.
  • US Booking MarketplaceFull-stack platform connecting service providers and consumers — service discovery, booking flows, and calendar integration.
  • HR CRM ToolAdmin panel with continuous UI/UX improvements, surfacing employee skills and experience insights for efficient people placement.
  • Internal Learning PlatformDeveloped and shipped a knowledge-sharing platform helping hundreds of employees learn and collaborate.
TypeScriptReactNext.jsJestStryker.jsDockerAWS
  • Fortune Global 500 engineering engagement
  • Shipped & maintained shared npm UI library adopted by 5+ teams
  • 4 products successfully delivered
  • Cross-functional collaboration at scale

Fintech · Enterprise · Accounting & Analytics · AI-powered EdTech

Devtech - Software Development Company

2 client projects · Aug 2021–Sep 2022

  • Enterprise Accounting Platform (USA)Transformed the UI of a legacy enterprise system into a modern, scalable frontend aligned with current engineering best practices. Delivered financial reporting dashboards, lease accounting flows, and performant data-heavy UI components.
  • AI-Powered Microsoft-365 Enablement PlatformOwned the frontend implementation of advanced data visualization features, building custom standalone D3.js chart components to render complex, large-scale datasets.
TypeScriptNext.jsReactD3.jsRedux ToolkitPostgreSQLAzure
  • Enterprise platform modernized
  • Custom D3.js data visualizations
  • AI-powered learning platform
  • High-performance analytics dashboards

My Services

How I can help

01

Build Your Product

From idea to production-ready software.

Whether you're validating a new idea, launching an MVP, or scaling an existing product, I will help you transform your vision into a scalable web solution with a strong technical foundation, clean architecture, and maintainable code. AI accelerates my development workflow—so you ship faster without compromising quality.

  • Production-ready MVP or SaaS application
  • Scalable architecture that grows with your business
  • Faster time-to-market without sacrificing quality
  • Clean, maintainable code built for long-term success
02

Technical Consulting

Solve the problems slowing your team down.

Need a second opinion on the front-end architecture, performance bottlenecks, scalability or some other type of complexity? I help teams identify root causes, make informed technical decisions, and define a clear path forward.

  • Clear diagnosis of bottlenecks and technical debt
  • Actionable architecture and performance recommendations
  • Informed decisions on tech stack and tooling
  • A defined path forward for your team
03

Modernize & Scale

Improve what already works.

Legacy applications don't always need a rewrite. I help teams modernize codebases, introduce scalable architecture, establish design systems, improve performance, and reduce long-term maintenance costs without disrupting product development.

  • Legacy codebase modernized without service disruption
  • Scalable architecture and established design system
  • Improved performance and Core Web Vitals
  • Reduced maintenance costs and technical debt

Trusted by teams at

Paayed
Inditex
FinQuery
Symphony
Devtech
Nulia
Fitcher
Paayed
Inditex
FinQuery
Symphony
Devtech
Nulia
Fitcher

Writing

Thinking out loud.

Articles on frontend engineering, design systems, and building software that's maintainable at scale.

Tech

Tools of the trade

Languages

TypeScriptJavaScriptPHP

Frontend

ReactNext.jsAstroTailwindRadix UIMaterial UIRedux ToolkitD3.jsSass

Testing

JestRTLStryker.jsStorybookVitest

Backend & Data

Node.jsPostgreSQLMySQLMongoDBPrismaFirebase

Infra & DevOps

DockerGitHub ActionsJenkinsViteWebpack

AI Tools

GitHub CopilotClaudeCursorGemini

Auth & Tooling

Auth0ESLintGitFigma

Let's Connect

Let's build something powerful together

Book a free discovery call. No sales pitch — just an honest conversation about your challenges and whether I can help.

What I'm looking for

  • Senior frontend roles
  • Full-stack roles (Next.js or Node.js)
  • Complex products at scale
  • Teams that care about craft
  • Remote or hybrid (Serbia-based)

Response time

I typically respond within 24 hours. If it's urgent, mention it in the subject line.

Location

Niš, Serbia

UTC+1 (CET) / UTC+2 (CEST)