Meet Upstaff Team
Python 5yr.
Django 3yr.
Mobile development
Flask
API
- Python Developer with 6+ years of experience in backend development and automation: Django (4 years), Flask, and Fast API for web application development;
- Built and supported Telegram bots and automation tools for business operations (dApp Marketplaces, Crypto ATMs, Payments and Casino games)
- Maintaining and supporting production systems using FastAPI and SQLAlchemy, API integrations including financial services and crypto platforms;
- Docker containerization: Docker-compose, Docker via Render (serverless). Deployment and Linux server management (Ubuntu);
- Familiar with data reporting and basic analytics through internal monitoring tools; - Open to part-time and distributed team environments with a focus on ongoing system support.
- Reached the Top 10 freelance Python engineers on the local market at the age of 17 (showcasing early talent and initiative).
- Worked on projects with a multi-million user base, contributing to scalable architecture and high-load system stability.
- Successfully launched an educational platform in the USA, now actively used by students, tutors, and academic institutions.
- Represented the dev team at the international Wefi Beyond Banking Summit, delivering a product presentation to a global fintech audience.
Middle
Ternopil, Ukraine
JavaScript 8yr.
React 8yr.
TypeScript 5yr.
Node.js 5yr.
AWS
- 10+ years of experience in web development, M.Sc in Software Engineering, GAI, LLMs.
- Back-End: Node.js, Next.js, TypeScript , PHP, Java (Basics).
- Front-End: JavaScript & TypeScript (React, Angular, Vue.js).
- Mobile: React Native.
- AWS Cloud infrastructure, Lambda/Serverless, SNS/SQS Queues.
- Control systems (e.g., Git) and familiarity with DevOps practices for continuous integration and deployment (CI/CD).
- Unit testing, integration testing, and end-to-end testing.
- Experience leading and mentoring a team of developers, including assigning tasks, providing guidance, and ensuring the team's success. Conducting assessments and interviews remotely. Ability to motivate and inspire team members, resolve conflicts, and provide constructive feedback.
Architect/Team-lead
Ukraine
Haskell 3yr.
Scala 2yr.
Plutus 2yr.
Akka
Cardano
- 3 years of experience in Plutus / Cardano smart contracts developer role (Plutus Core, Plutarch)
- Cardano ecosystem knowledge
- Haskell, Scala, Cabal/Stack, GADTs/Type families, Generics, Servant, lenses, mtl, free monads - senior-level professional
- Functional programming with FRP, Redux, Event sourcing, Category theory
- OOP, OOD, UML, Design patterns, SOLID, DI. TDD, BDD, Unit, functional, and integration testing
- 14 years of experience in software engineering
Senior
Ukraine
Node.js 5yr.
React 3yr.
Solidity
NFT
• 15+ years of commercial software development experience
• Solid knowledge of Solidity, C++, JavaScript, TypeScript;
• Deep understanding of blockchain architecture and smart contract logic;
• Cosmos, Tron, Avalanche, Binance Smart Chain, Ethereum dApps;
• Strong skills in developing NFT smart contracts. Support and payload verification;
• NFT Marketplaces (ERC - 721/1155), Crypto Payment Solutions & DeFi Cross Chain Bridges - ERC-20 Tokens, ICO, DEX, Staking, Swapping;
• Highly qualified knowledge of Stripe payment system integration to blockchain data;
• 10+ years experience working with Python;
• 5 years experience working with Node.js;
• Strong abilities with Express;
• Experience working with Docker, and Kubernetes (K8s);
• 3+ years of development experience with React.js.
• No scheduled vacations within the next 3 months;
Senior
Ukraine
$55/hr
$8000/month
$8000/month
Python
Django
Flask
- 5 years of experience in the IT industry as a Python Engineer
- Proficient in using technologies such as Django DRF, Flask, Pandas, BeautifulSoup, SQLAlchemy, Asyncio, Flask + Marshmallow, Apscheduler, Jinja, Quip API, Docker, Nginx, Amazon MWS API, Amazon SP-API, Google API, and Telegram API;
- Strong in refactoring, bug-fixing, and working with Python, JavaScript, Django, Django Rest Framework;
- Skilled in developing faceted search and matching algorithms using ElasticSearch;
- Experienced in PDF generation and importing from various formats;
- Developed web applications, API interfaces, and automated scripts for data transformation;
- Previous experience includes working as a Python developer focused on data scraping for Amazon, eBay, and Walmart products in dropshipping projects;
- Also worked as a C# developer on various projects, specializing in web development, scraping, and parsing data;
- Upper-Intermediate English;
- Available ASAP
Senior
United States
PHP 9yr.
JavaScript 9yr.
MySQL 9yr.
Solidity
- 10+ years experience as a Full-Stack Developer with of developing robust web applications and services, including extensive experience in both frontend and backend technologies;
- Technical proficiency with PHP and MySQL for server-side development, advanced JavaScript utilization on the client side;
- Strong abilities with blockchain technology engagement, including smart contracts and wallet development using Solidity, Hardhat, Truffle, WalletConnect, and Metamask SDK;
- Experienced with libraries Web3.js, and Ethers.js;
- Ability to work Ethereum Blockchain, Binance Smart Chain (BSC), with different wallets including MetaMask;
- Adept at working with a variety of frameworks and languages beyond core competencies, such as Laravel, Solidity, Node.js, and C++;
- Up-to-date with modern practices, possessing comprehensive experience in codebase upgrades, performance optimization, and integrating third-party APIs;
- Successfully led a development team, demonstrating strong leadership and project estimation skills.
Senior
Ukraine
JavaScript 6yr.
Node.js
NestJS
Express
Fastify
- Full-stack engineer with 6+ years of experience with scalable architectures, clean APIs, and responsive interfaces
- Developed and implemented backend systems for fintech and crypto applications using Node.js, NestJS, and Prisma, including integrations with multiple payment providers and API gateways, resulting in scalable architectures handling diverse data formats.
- Optimized database interactions and workflows in corporate platforms with AWS Neptune, DynamoDB, Elasticsearch, and Redis, accelerating integration tests by 15% through redesigned test environments.
- Built asynchronous event handling and caching mechanisms with NATS, Redis, and BullMQ for product management and payment systems, improving reliability via message-driven communication.
- Integrated monitoring tools like Prometheus and Grafana in deployment pipelines using GitLab CI, enabling metrics collection for endpoints and integrations in real-time services.
Senior
Bialystok, Poland
JavaScript 9yr.
React 8yr.
TypeScript
- Front-end JavaScript Engineer with 9 years of commercial experience;
- 8+ years of hands-on experience with React, and TypeScript, including complex component architectures, shared UI libraries, and micro-frontend approaches using Module Federation;
- Experience with automated testing, covering unit, integration, and end-to-end tests using Jest, React Testing Library, Cypress, and Playwright;
- Experience with Next.js, focusing on performance optimization, scalability, and modular application design;
- Expertise in Web3 and blockchain integrations, including crypto wallets, on-chain data, and decentralized authentication;
- Background in FinTech and crypto products, delivering secure, user-facing interfaces for wallets, cards, and transaction flows;
- Experience working and leading within distributed Agile teams, collaborating closely with backend, security, and product stakeholders.
Senior
Castel San Giovanni, Italy
JavaScript
TypeScript
Node.js
React
- 8+ years of experience in software development with a focus on JavaScript, TypeScript, and full-stack engineering;
- Computer Science Education: A reliable and collaborative team member with a proactive approach to problem-solving
- Developed cross-platform interfaces, including AI-powered chatbots with Whisper and Heygen, and real-time messaging platforms;
- Built complex web applications using React.js, React Native, Angular, and View.js (pet) across edtech, healthtech, e-commerce, and banking projects; Worked with Redux Toolkit, RxJS, Nest.js, and Express for state management and backend logic;
- Delivered serverless APIs using AWS Lambda, API Gateway, Cognito, and integrated MongoDB via Mongoose;
- Built and maintained responsive UIs with accessibility, mobile support, and data visualization features; performed performance optimization, refactoring, bug fixing, and CI/CD using the Serverless Framework;
Senior
Krakow, Poland
JavaScript 10yr.
TypeScript 10yr.
Node.js 10yr.
React 10yr.
PostgreSQL 10yr.
- 10+ years of experience designing and leading complex software solutions in fintech, AI, and payment systems, with expertise in JavaScript, TypeScript, Node.js, Python, Kubernetes, AWS and GCP services.
- Computer science education with applied physics and software development degrees, combined with hands-on expertise in DevOps, CI/CD pipelines, and advanced testing methodologies (TDD, BDD). Deep knowledge of software design principles, event sourcing, REST/GraphQL APIs, container orchestration, and secure, high-performance distributed systems.
- Architecting scalable, event-sourced payment hubs, AI-driven platforms, and multi-modal AI assistants using microservices, FastAPI, LangGraph, and Terraform.
Senior
Kaunas, Lithuania
Python 9yr.
SQL 6yr.
Databricks
PySpark
- 9 years experience with various data disciplines: Data Engineer, Data Quality Engineer, Data Analyst, Data Management, ETL Engineer
- Built and optimized production-grade PySpark pipelines handling millions of records, including complex transformations, joins, aggregations, and backfills, with a strong focus on performance and data quality.
- Automated Web scraping (Beautiful Soup and Scrapy, CAPTCHAs and User agent management)
- Data QA, SQL, Pipelines, ETL
- Data Analytics/Engineering with Cloud Service Providers (AWS, GCP)
- Extensive experience with Spark and Hadoop, Databricks (hands-on with Spark-based pipelines deployed in cloud environments and have used Databricks as the execution and collaboration layer: jobs, notebooks, cluster configs).
- 7 years of experience working with MySQL, SQL, and PostgreSQL;
- 5 years of experience with Amazon Web Services (AWS)
- Google Cloud Platform (GCP): BigQuery, GCS, App Engine, data pipelines, and Azure (basic knowledge)
- Data Analytics/Engineering services, Kubernetes (K8s)
- 5 years of experience with PowerBI
- 4 years of experience with Tableau and other visualization tools like Spotfire and Sisense;
- 3+ years of experience with AI/ML projects, background with TensorFlow, Scikit-learn and PyTorch;
- Extensive hands-on expertise with Reltio MDM, including configuration, workflows, match rules, survivorship rules, troubleshooting, and integration using APIs and connectors (Databricks, Reltio Integration Hub), Data Modeling, Data Integration, Data Analyses, Data Validation, and Data Cleansing)
- Upper-intermediate to advanced English
Senior
Portugal
Python
MatLab
TensorFlow
PyTorch
- Machine Learning and Data Engineer with 10+ years of professional experience.
- Knowledge of a wide range of programming languages, technologies and platforms, inc Python, JavaScript, C/C++, MATLAB;
- Extensive experience with designing and academic analysis of AI/ML algorithms, data analytics, mathematical optimization, modern statistical and stochastic models, robotics;
- Determining and analyzing business requirements, communicating with clients and architecting software product;
- Solid experience in engineering and design of robust and efficient software products;
- Track record of performing as a member of large-scale distributed engineering teams;
- Strong knowledge of OOP/OOA/OOD, database modeling;
- Experience with cutting edge Semiconductor Engineering;
- Proficient in writing and presentation of grants, projects reports and documentation;
- Fluent English;
- Upper-Intermediate German and Dutch.
Senior
Rotterdam, NetherlandsOur most common engagement models
Project-based Model
Get a custom platform design along with any other services you might need (expert consultations, product design, web engineering, digital platforms, mobile application development, Operations and Clouds, Data and Analytics, Desktop, Embedded systems, Blockchain, No-code/Low-code, Website optimization, SEO and much more) at a fixed price.
Dedicated Development Team
Get a dedicated team of software developers working on your project according to our flexible time and materials payment scheme.
Consulting
We help our clients to identify the potential of a software development for their organization including market research, project’s feasibility assessment, analysis of blockchain platforms, tools, right features prioritization.
Case Studies
We closely collaborate with recruitment & talent acquisition teams on urgent or hard-to-fill positions. Discover how startups and top-tier companies benefit.
Frequently Asked Questions
What is Upstaff?
Upstaff is a service company with its own in-house engineering, and management competence, leveraging the community of software development companies’ resource network.
When can my team start work?
Our developers can start immediately or within two weeks after the project is confirmed.