I help startups and SaaS companies build software that continues to scale as the product grows.
I enjoy joining projects at the point where things stop being simple.
Maybe your product has grown faster than expected. New features are getting harder to ship, technical debt is slowing the team down, or the architecture that worked for the first version is starting to show its limits. That's usually where I can help.
For the past 12+ years, I've been helping teams turn ideas into production software - and, just as importantly, keep that software maintainable as the business evolves.
I work across the entire stack, from modern frontend applications to backend architecture and infrastructure. But clients don't hire me because I know React, Laravel, Vue, or any other framework. They hire me because I can quickly understand a complex system, make sound technical decisions, and build solutions that other engineers can confidently extend months or years later.
Over the last few years, AI has naturally become part of my work. I've integrated LLMs into existing SaaS platforms, built AI-powered features and internal tools, automated workflows, and used AI to speed up development without sacrificing engineering quality. I don't build AI for the sake of it - I use it when it solves a real problem and delivers measurable value.
One thing clients often tell me is that they don't have to manage me. I communicate clearly, ask the right questions early, and take ownership of the work. If I see a simpler solution, I'll suggest it. If I think a decision is likely to become technical debt six months from now, I'll raise that concern before we write the code.
Beyond web development, I also work with Rust and systems programming, including Solana smart contracts, SDK development, asynchronous programming with Tokio, concurrency, and performance-critical software. That experience has shaped the way I think about performance, reliability, and software architecture across every project I work on.
Whether you're building a new SaaS product, scaling an existing platform, modernizing a legacy application, or adding AI capabilities to your product, I'd be happy to help.
Technologies
Languages: TypeScript, PHP, Rust
Frontend: React, Next.js, Vue, Nuxt, Angular, NgRx, TanStack Query, Redux Toolkit, RTK Query, Pinia, Tailwind CSS, SSR, SSG, Hybrid Rendering
Backend: Laravel (Octane, Horizon, Cashier, Sanctum), REST APIs, GraphQL, WebSockets, Queue-based & Event-driven Architecture, Node.js
AI: OpenAI, Anthropic, LLM integrations, AI-powered features, AI workflows, MCP, Prompt Engineering, AI-assisted development, Claude Code, Codex, ChatGPT
Databases & Infrastructure: PostgreSQL, MySQL, Redis, ClickHouse, Supabase, Docker, CI/CD
Payments & SaaS: Stripe, Subscription Billing, Multi-tenant Architecture
Blockchain & Systems: Solana, Rust, SDK Development, Tokio, Async Programming, Concurrency, Serialization
Testing: PHPUnit, Vitest, React Testing Library
React
Node.js
Angular
Tailwind CSS
Redux
RxJS
Laravel
Stripe
PHP
PostgreSQL
Next.js
SaaS
TypeScript
Nuxt.js
Vue.js
AWS CloudFront
Docker Compose
SaaS Development
AI App Development
NestJS
Maxim K.
Malaga, Spain
$70/hr
5.0
24 jobs
"The only way to go fast, is to go well." - Robert C. Martin aka "Uncle Bob"
Software architect and developer since 2007.
Kum Software agency co-founder and mentor.
Microsoft Certified Windows Applications developer.
Master degree in engineering.
Most recent experience:
1) .NET 6-8, Kafka, Redis, Couchbase, SQL Server, Microservices, Docker, k8s
2) Angular 12-17, Micro Frontends, RxJs, NgRx, NgXs, Angular Material, TestCafe
3) Typescript, Node.js, Nest.js, express, koa, Apollo GraphQL, Jest
4) Auth0, Stripe, HelloSign
Testimonials:
"Max is one of the best software developers I have worked with in my career. Not only is he great at thinking through problems from the business level all the way down to architecture and implementation, he communicates well and can explain the rationale for decisions so everyone is on the same page. Highly recommended." - Jon Elling, Founder and CEO, Maverick Retirement
"It was a pleasure working with Maxim, will recommend and we will definitely work with him in the future. Finding developers of his caliber and attitude is always challenging."
"Max is fantastic. I have been hiring developers for over 10 years and I am a developer myself and Max is one of the best I have ever hired. He communicates well, he thinks through problems well, and his code is nice and clean. Highly recommended."
Windows Presentation Foundation
C#
.NET Framework
ASP.NET MVC
RESTful Architecture
Windows App Development
Windows Forms
AngularJS
Node.js
Desktop Application
Michael S.
Madrid, Spain
$70/hr
4.7
84 jobs
I help business owners cut AI costs by up to 70% through research and consulting services that actually deliver.
10+ years of commercial experience in ML, NLP, NLU, NLG, and Agentic AI Systems
✅ Helped brands like Adnoc ($12.38B market cap) and Rogers ($24.21B market cap)
✅ Data-driven methodology with measurable outcomes
✅ References from AI opinion leaders
✅ No vendor lock-in, no technical BS, just results
Consulting/Research Results in Numbers:
Average reduction in project expenses: 20-70% cost reduction
Average acceleration in integration and development cycles: 40-80% faster
Customer Satisfaction Score (CSAT): 95%
CONSULTATIONS FOR DESIGN & DEVELOPMENT OF:
Proof of Concept (POC), Prototypes, Demos, Production-ready products:
Scientific paper reproduction and implementation
Complex AI applications for text and multimodal understanding
Agentic AI systems and autonomous workflows
Data-rich systems for text and document processing
Advanced RAG (Retrieval-Augmented Generation) architectures
Search / Question-Answering systems
Text / Document classification and analysis
Ontology-based and knowledge graph systems
Text clustering and semantic analysis
Knowledge representation systems
Multimodal generation pipelines (text, image, video, audio)
AI agents, chatbots, and prompt engineering
Large-scale language model fine-tuning and deployment
ML models benchmarking, profiling, and optimization
Graph neural networks and analysis
Document intelligence and extraction
Computer vision and multimodal AI systems
Other? Just send me a message!
Additional Services:
Data-rich SaaS applications with microservice architecture
SDLC best practices, CI/CD pipelines
Scrum / Agile methodologies
Training and Masterclasses:
Generative AI and ML bootcamps (2-3 days)
AI risk management best practices (3-5 hours)
AI integration best practices (2-3 days)
Agentic AI and autonomous systems (2-3 days)
Generative AI innovations management (1-2 days)
Team Building:
Need a team? I help with targeted AI team creation from scratch, hiring AI experts, and technical interviews/skills assessment.
Other? No problems, just write me a message
* The money-back guarantee program is exclusively tailored for established companies meeting specific criteria: a minimum annual revenue of over $500k, a track record of at least 5 years in the market, a strong reputation, and possessing all necessary legal and tax documentation. Requires additional contract before we start. Ask me for the details. This program ensures a refund if the service fails to meet your expectations.
Natural Language Processing
Software Architecture & Design
Machine Learning
Deep Learning
Data Science
Artificial Neural Network
Artificial Intelligence
Feature Extraction
Google Cloud Platform
Solution Architecture
Data Analysis
API
Generative AI
LangChain
LLaMA
Evgenii R.
Gandia, Spain
$70/hr
5.0
52 jobs
Hello.
From early 200x I develop wide range of commercial products including desktop application, large scale enterprise applications and web sites. Starting with C++ and WinApi now I developing on C# and .Net. I'm highly focused on application performance, usability, maintainability, portability, and scalability. I strictly follow the Object Oriented Programming paradigm and use Design Patterns, where appropriate. Also I'm experienced in database design/implementation and use all means necessary to achieve maximal data consistency, integrity and availability.
1st place in SQL and top 10% in C# Upwork tests.
Web Development:
HTML 5
JavaScript
ASP.NET MVC
ASP.NET Core
Angular
Razor
Desktop Development:
WPF
XAML
Winforms
Telerik Controls
Data Base:
Entity Framework
NHibernate
SQL
Microsoft SQL Server
Oracle
PostgreSQL
MySql
HTML5
.NET Framework
jQuery
C#
SQL
C++
OpenCV
Model View ViewModel
Oracle PLSQL
Image Processing
Daniel M.
Vigo, Spain
$13/hr
4.5
1 jobs
I am a software engineer with a background in web/mobile
Development and a degree in Digital Games Technology from the
Infnet Institute. I have been involved in projects related to urban
mobility, virtual reality, and social networks, utilizing technologies
such as Flutter, NodeJS, TypeScript, AWS, Azure, among others. My
skills include requirements definition, software architecture, front-end
and back-end development, API integration, database management,
and devops.
In my recent projects, I have contributed to the development of
innovative and impactful applications, such as SotreqLink Campo,
an equipment management system for the mining and construction
sector, Vite, an urban mobility platform connecting users and drivers,
and SMART FANS, a virtual reality solution for the sports market. In
these experiences, I have applied and enhanced my skills in Flutter,
NodeJS, TypeScript, MongoDB, Microservices, AWS, Azure, among
others.
Flutter
Dario D.
Tiana, Spain
$25/hr
5.0
1 jobs
I am looking for a side hustle that can inspire me and where i can put my experience and brain to the test.
I love problem solving and challenges, have extensive experience in development in several languages (c++ c# delphi). Worked mainly in standalone windows applications and i am very confortable with all related technologies (.NET framework, .NET, WPF, WinForms).
I have worked for a CAD/CAM company mostly since i graduated developing complex systems like the 3D graphics engine (OpenGL), simulation system, complex tessellation algorithm plus managing projects and now directing the development department.
On the other hand, i have done some data update, merge, migration and verification tools for the company to be able to connect our CRM with the license system and other systems and do control panels and graphs using google looker studio.
As well I have done some web applications (static PHP, JS, CSS) and understand well the architecture of them, although i would say it is not my main area of expertise or enjoyment.
I have dabbled with Unity and Unreal Engine in some personal projects. I can basically learn any new language/IDE/framework/API quite fast as i have used many for company or personal projects.
I like hands on projects, complex with ambitious goals that seem unattainable at first glance and with plenty of everyday challenges.
One of my biggest strenghts is performance enhancement on complex systems, i have done remarkable improvements on performance over large projects attaining results one or 2 orders of magnitude faster. For example, i was working in a system improving the 3D graphics and painting of a production software, with the model part used the painting took 120ms, after optimizations it painted under 16ms. Another example, a chaining algorithm of curve elements was taking 150s in chaining a complex profile, after the optimizations i applied it went down to 500ms.
C++
C++/CLI
C#
Scrum
Agile Software Development
Project Management
UX & UI
Desktop Application
Software Architecture & Design
Software Design Pattern
Software Development
Standalone Application
OpenGL
Computer Graphics
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