Senior Full Stack Software Engineer - .NET/React (391)
Status
Florianópolis, Brazil
Full time
Remote
Compensation is not specified
Role
Software Engineer
Description
Want to take your international career to the next level?
If yes, Ubiminds can assist you!
Ubiminds is a people-first company that collaborates with American software product companies to expand their development capabilities by curating top 5% talent from Brazil. They offer a unique combination of staff augmentation and employer-of-record services to support the LATAM strategy of their partner companies.
Join Ubiminds and be part of a company that is revolutionizing the talent acquisition process for organizations worldwide. Their end-to-end hiring platform features innovative tools like video interviewing, assessments, and conversational AI. With a focus on modern hiring solutions powered by ethical AI, they have facilitated millions of video interviews and candidate engagements for numerous global clients.
This is an exceptional opportunity to progress your career on an international stage while contributing to a cutting-edge organization.
Role Overview:
Ubiminds is seeking a Senior Full Stack Software Engineer to be a part of their platform team. In this role, you'll be responsible for maintaining and enhancing critical codebases, with a focus on backend systems built on .NET and frontend components utilizing React and TypeScript. Collaborating closely with other engineers and cross-functional teams, you will work on issue resolution, system reliability improvements, and delivering incremental enhancements, with potential to take on more feature-driven projects in the future.
Key Responsibilities:
- Design, develop, and manage robust .NET Core services and APIs within a microservices architecture.
- Create responsive and accessible frontend experiences using React and TypeScript.
- Write clean, scalable, and testable code following contemporary engineering practices.
- Support automated test coverage for ensuring high-quality releases.
- Participate in design reviews, code reviews, and technical planning.
- Contribute to identifying and reducing technical debt in the platform.
Requirements:
Mandatory Skills:
- 7+ years of experience with .NET Core/C# for web applications.
- Proficient in REST APIs and microservices design.
- Familiarity with cloud platforms like Azure, AWS, or GCP.
- Strong command of JavaScript, HTML, CSS, and frontend frameworks such as React.
- Experience with relational databases and ORMs like Entity Framework Core.
- Knowledge of Git workflows and best practices in source control.
- Basic proficiency in English language for reading documentation, variable naming, and code comments.
- Ability to collaborate effectively in distributed, remote teams.
Nice to Have:
- Background in high-scale enterprise platforms.
- Experience with automated testing tools like xUnit, NUnit, Jest, or Cypress.
- Proficiency in Docker, Kubernetes, or other container orchestration tools.
- Familiarity with observability tools such as OpenTelemetry, Datadog, etc.
- Exposure to legacy-to-modern migration projects.
- Understanding of secure coding principles.
Perks and Benefits:
At Ubiminds, as a Senior Full Stack Software Engineer, you'll enjoy:
- Work within a product-based company, treated like a full-time employee.
- Access to full back-office support, including career guidance and concierge services.
- Remote-first policy with a distributed team.
- Provided with a MacBook for work.
- Opportunities for personal growth through tech talks, chapter meetings, and remote networking events.
- Free English lessons to enhance communication skills.
- Candidate referral bonus program for promoting the company to tech friends.
- Optional access to the Florianópolis headquarters with perks like massages, snacks, soft drinks, and games.
Hiring Process:
- Initial interview with Tech Recruiter to discuss the job opening.
- Client process involving technical challenges and assessments.
- Job offer.
Skills Required
Ubiminds
Website
Not specified
Company size
Not specified
Location
United States
Description
Not specified
Status
Astra Byte Sync
Blockchain Specialist for Game-Fi Project
Full time
Remote
We are seeking a skilled Blockchain Specialist to become a part of our groundbreaking Game-Fi initiative! If you have a deep passion for gaming, decentralized finance, and the latest technological advancements, this could be your ideal role.
Primary Duties:
- Create and implement smart contracts for in-game transactions and assets.
- Develop secure blockchain solutions that guarantee player ownership and protect asset integrity.
- Work closely with our game development team to smoothly incorporate blockchain technology into our gaming platform.
- Keep abreast of the latest developments and best practices within the blockchain and gaming sectors.
Qualifications:
- Demonstrated experience as a Blockchain Developer or in a similar position.
- Expertise in Solidity, with experience in Ethereum or other blockchain technologies.
- Solid understanding of Game-Fi principles and how blockchain can elevate the gaming experience.
- Familiarity with DeFi protocols and tokenomics.
- Ability to work effectively within a team and convey technical information to non-technical audiences.
Desirable Skills:
- Experience in NFT development and related platforms.
- Understanding of cryptographic concepts and security best practices.
If you are eager to embrace a new challenge and contribute to the evolution of gaming through blockchain technology, we would love to hear from you!
Primary Duties:
- Create and implement smart contracts for in-game transactions and assets.
- Develop secure blockchain solutions that guarantee player ownership and protect asset integrity.
- Work closely with our game development team to smoothly incorporate blockchain technology into our gaming platform.
- Keep abreast of the latest developments and best practices within the blockchain and gaming sectors.
Qualifications:
- Demonstrated experience as a Blockchain Developer or in a similar position.
- Expertise in Solidity, with experience in Ethereum or other blockchain technologies.
- Solid understanding of Game-Fi principles and how blockchain can elevate the gaming experience.
- Familiarity with DeFi protocols and tokenomics.
- Ability to work effectively within a team and convey technical information to non-technical audiences.
Desirable Skills:
- Experience in NFT development and related platforms.
- Understanding of cryptographic concepts and security best practices.
If you are eager to embrace a new challenge and contribute to the evolution of gaming through blockchain technology, we would love to hear from you!
Payment in Crypto
Winnables
Full Stack Developer (Front End Leaning)
Full time
Remote
Job Description:
Winnables.com is looking for a creative front-end-leaning Full Stack Developer who loves bringing slick, engaging user experiences to life while still caring about the behind-the-scenes details.
You’ll collaborate closely with designers and product leads, iterate quickly on new ideas, and see the direct impact of your work in the hands of players around the world.
If you enjoy mixing imaginative front-end polish with just enough back-end know-how to make the magic happen, we’d love to hear from you.
Key Responsabilities:
Transform design mock-ups and product concepts into polished, responsive game screens, animations, and flows.
Collaborate daily with designers, product leads, and blockchain engineers to prototype, ship, and iterate on new games or new features.
Continuously test, debug, and optimize for performance across devices and network conditions.
Review code, share best practices, and help keep our small codebase clean, secure, and easy to extend.
Use player feedback and analytics to refine existing features and guide new ideas from concept to launch.
Champion accessibility and web-standards compliance, ensuring every player—regardless of device or ability—has a first-class experience.
What You’ll Be Building
Build interactive mini-games that deliver smooth, responsive gameplay.
Create real-time multiplayer features and live game mechanics.
Develop pack-opening systems with eye-catching, engaging animations.
Engineer raffle and lottery-style games that are fully on-chain and provably fair.
Implement Plinko and other physics-based games, tuned for fun and balance.
Craft user-friendly interfaces that perform flawlessly across mobile, tablet, and desktop.
Qualifications:
Tech Stack:
Core: TypeScript · React & Next.js · Node.js · Zustand · WebSockets & REST
Data & Infra: PostgreSQL (Supabase) · Redis · Docker · GitHub
Observability: Grafana · PostHog
Design & Web3: Figma · viem / wagmi
What We're Looking For
Strong experience with TypeScript and modern JavaScript
Solid understanding of React and Next.js ecosystem
Experience building real-time applications with WebSockets
Familiarity with Node.js backend development
Knowledge of PostgreSQL and database design
Experience with responsive design and mobile-first development
Understanding of state management patterns (Zustand experience preferred)
Understanding of web security fundamentals (CSRF protection, secure authentication flows, input validation)
Interest in gaming mechanics and interactive user experience.
Nice to Have
Experience with gaming or interactive application development
Knowledge of blockchain technologies and Web3 integration
Familiarity with monitoring tools (Grafana, PostHog)
Experience with Docker and containerization
Understanding of real-time multiplayer game architecture
Company Description:
Winnables.com is on a mission to re-imagine iGaming through full on-chain transparency. We believe players deserve provably fair odds, transparent math, and no black-box RNGs. Every spin and ticket purchase is recorded immutably on Ethereum, so anyone can audit the outcome, track prize pools, or even build their own analytics on top of our contracts.
All of our games are designed and engineered 100% in-house by a small, senior team that blends game design, cryptography, and smart-contract security. We currently operate two flagship experiences:
Raffles – transparent prize drawings where every ticket lives on-chain, letting players verify fairness before and after the draw.
Loot Packs – blockchain-powered loot boxes that reveal randomized rewards with engaging pack-opening animations.
We’re still just getting started. The roadmap is full of green-field challenges—and real, measurable impact on an industry ripe for change. Join us and help craft the next generation of fair, fun, and truly player-owned gaming.
Winnables.com is looking for a creative front-end-leaning Full Stack Developer who loves bringing slick, engaging user experiences to life while still caring about the behind-the-scenes details.
You’ll collaborate closely with designers and product leads, iterate quickly on new ideas, and see the direct impact of your work in the hands of players around the world.
If you enjoy mixing imaginative front-end polish with just enough back-end know-how to make the magic happen, we’d love to hear from you.
Key Responsabilities:
Transform design mock-ups and product concepts into polished, responsive game screens, animations, and flows.
Collaborate daily with designers, product leads, and blockchain engineers to prototype, ship, and iterate on new games or new features.
Continuously test, debug, and optimize for performance across devices and network conditions.
Review code, share best practices, and help keep our small codebase clean, secure, and easy to extend.
Use player feedback and analytics to refine existing features and guide new ideas from concept to launch.
Champion accessibility and web-standards compliance, ensuring every player—regardless of device or ability—has a first-class experience.
What You’ll Be Building
Build interactive mini-games that deliver smooth, responsive gameplay.
Create real-time multiplayer features and live game mechanics.
Develop pack-opening systems with eye-catching, engaging animations.
Engineer raffle and lottery-style games that are fully on-chain and provably fair.
Implement Plinko and other physics-based games, tuned for fun and balance.
Craft user-friendly interfaces that perform flawlessly across mobile, tablet, and desktop.
Qualifications:
Tech Stack:
Core: TypeScript · React & Next.js · Node.js · Zustand · WebSockets & REST
Data & Infra: PostgreSQL (Supabase) · Redis · Docker · GitHub
Observability: Grafana · PostHog
Design & Web3: Figma · viem / wagmi
What We're Looking For
Strong experience with TypeScript and modern JavaScript
Solid understanding of React and Next.js ecosystem
Experience building real-time applications with WebSockets
Familiarity with Node.js backend development
Knowledge of PostgreSQL and database design
Experience with responsive design and mobile-first development
Understanding of state management patterns (Zustand experience preferred)
Understanding of web security fundamentals (CSRF protection, secure authentication flows, input validation)
Interest in gaming mechanics and interactive user experience.
Nice to Have
Experience with gaming or interactive application development
Knowledge of blockchain technologies and Web3 integration
Familiarity with monitoring tools (Grafana, PostHog)
Experience with Docker and containerization
Understanding of real-time multiplayer game architecture
Company Description:
Winnables.com is on a mission to re-imagine iGaming through full on-chain transparency. We believe players deserve provably fair odds, transparent math, and no black-box RNGs. Every spin and ticket purchase is recorded immutably on Ethereum, so anyone can audit the outcome, track prize pools, or even build their own analytics on top of our contracts.
All of our games are designed and engineered 100% in-house by a small, senior team that blends game design, cryptography, and smart-contract security. We currently operate two flagship experiences:
Raffles – transparent prize drawings where every ticket lives on-chain, letting players verify fairness before and after the draw.
Loot Packs – blockchain-powered loot boxes that reveal randomized rewards with engaging pack-opening animations.
We’re still just getting started. The roadmap is full of green-field challenges—and real, measurable impact on an industry ripe for change. Join us and help craft the next generation of fair, fun, and truly player-owned gaming.
Jack Milton
Full Stack Developer (Web3/Crypto)
London, UK
London, UK
Full time
Remote
We're hiring a full stack developer to help build a suite of Web3 products - lightweight tools designed to scale fast. You’ll work directly with the founding team to ship high-impact tools used by founders, investors, and crypto communities.
Over the next 4–6 months, we’re rolling out four standalone products - including a Web3 project directory, a community engagement platform, and other tools designed to drive discovery and visibility across the space. You’ll have end-to-end ownership of what you ship.
Tech Stack & Skills:
React / Next.js or similar (full stack comfort)
Node.js, Firebase, or lightweight backend setups
CMS integration (Sanity, Notion, Airtable, etc.)
REST APIs, data scraping, automation
Strong grasp of Web3 (tokens, on-chain data, dApps)
Bonus: Vercel, CoinMarketCap API, any Web3 SDKs
Who this is for:
You’ve built and shipped products solo or with small teams
You’re crypto-native and enjoy exploring new tools/protocols
You’re fast, self-driven, and prefer ownership to micromanagement
You write clean code but iterate quickly
What Success Looks Like (First 60 Days)
Launch 1–2 working products with CMS and frontend live
Build automation for token sourcing + database updates
Deliver clean UIs with fast-loading pages and working filters
Support backend tools for campaign dashboards or scraping
Details
Full-time (contractor, with option to go permanent)
Remote + async (Europe/Asia timezone preferred)
Competitive base + performance bonuses
No corporate fluff - just fast builds, useful products, and full ownership
To apply:
Send GitHub, portfolio, or 1–2 examples of tools you’ve built solo or in a small team - especially anything Web3-related.
Over the next 4–6 months, we’re rolling out four standalone products - including a Web3 project directory, a community engagement platform, and other tools designed to drive discovery and visibility across the space. You’ll have end-to-end ownership of what you ship.
Tech Stack & Skills:
React / Next.js or similar (full stack comfort)
Node.js, Firebase, or lightweight backend setups
CMS integration (Sanity, Notion, Airtable, etc.)
REST APIs, data scraping, automation
Strong grasp of Web3 (tokens, on-chain data, dApps)
Bonus: Vercel, CoinMarketCap API, any Web3 SDKs
Who this is for:
You’ve built and shipped products solo or with small teams
You’re crypto-native and enjoy exploring new tools/protocols
You’re fast, self-driven, and prefer ownership to micromanagement
You write clean code but iterate quickly
What Success Looks Like (First 60 Days)
Launch 1–2 working products with CMS and frontend live
Build automation for token sourcing + database updates
Deliver clean UIs with fast-loading pages and working filters
Support backend tools for campaign dashboards or scraping
Details
Full-time (contractor, with option to go permanent)
Remote + async (Europe/Asia timezone preferred)
Competitive base + performance bonuses
No corporate fluff - just fast builds, useful products, and full ownership
To apply:
Send GitHub, portfolio, or 1–2 examples of tools you’ve built solo or in a small team - especially anything Web3-related.
Payment in Crypto
berttha walker
UI/UX Designer
Full time
Remote
UI/UX Designer for SaaS Dashboard (Figma)
Job Summary:
We're building ClearTrack, a lightweight SaaS tool for tracking tasks and performance in remote teams. We're looking for a UI/UX designer to design 6–8 clean, modern dashboard screens (desktop + mobile).
Scope of Work:
1. Design dashboard UI (Task List, Time Tracker, Reports, Settings)
2. Create responsive mockups in Figma
3. Deliver clickable prototype + style guide
4. Collaborate with our developer for smooth handoff
Budget:
Fixed: $800–$1200 (negotiable based on experience)
Requirements:
1. SaaS/dashboard UI design experience
2. Proficiency in Figma
3. Strong communication & fast turnaround
To Apply:
If you're interested, please:
1. Send a short proposal letter explaining why you're a good fit
2. Share your portfolio (SaaS/dashboard preferred)
3. Include your email address
4. Mention your availability and estimated delivery time
Bonus if you have:
Experience designing admin panels or productivity tools
Job Summary:
We're building ClearTrack, a lightweight SaaS tool for tracking tasks and performance in remote teams. We're looking for a UI/UX designer to design 6–8 clean, modern dashboard screens (desktop + mobile).
Scope of Work:
1. Design dashboard UI (Task List, Time Tracker, Reports, Settings)
2. Create responsive mockups in Figma
3. Deliver clickable prototype + style guide
4. Collaborate with our developer for smooth handoff
Budget:
Fixed: $800–$1200 (negotiable based on experience)
Requirements:
1. SaaS/dashboard UI design experience
2. Proficiency in Figma
3. Strong communication & fast turnaround
To Apply:
If you're interested, please:
1. Send a short proposal letter explaining why you're a good fit
2. Share your portfolio (SaaS/dashboard preferred)
3. Include your email address
4. Mention your availability and estimated delivery time
Bonus if you have:
Experience designing admin panels or productivity tools
Payment in Crypto
Astra Byte Sync
Web3 Gaming Platform Development Team
Full time
Remote
Company Overview
A fastest growing Blockchain company is looking to create a decentralized gaming platform that empowers players and developers alike. We are currently seeking to build a talented team to bring their vision to life.
Position Overview
We are looking for skilled professionals to join our development team for a Web3 gaming platform. The ideal candidates will be passionate about blockchain technology and gaming, and possess the expertise to contribute to various aspects of our project. We are hiring for the following roles:
1. Frontend Developers
Responsibilities: Design and implement user interfaces for the gaming platform using modern frameworks (e.g., React, Vue.js). Collaborate with UX/UI designers to create engaging and intuitive user experiences.
Qualifications: Proficiency in HTML, CSS, JavaScript, and relevant frameworks. Experience with Web3 technologies is a plus.
2. Backend Developers
Responsibilities: Develop and maintain server-side logic, database management, and API integration. Ensure the platform's performance, security, and scalability.
Qualifications: Strong knowledge of Node.js, databases (e.g., MongoDB, PostgreSQL), and experience with cloud services. Familiarity with blockchain technology is advantageous.
3. Blockchain Developers
Responsibilities: Design and implement smart contracts, manage blockchain integrations, and ensure the security of decentralized applications. Collaborate with the team to optimize blockchain performance.
Qualifications: Expertise in Solidity, JavaScript, Rust, or Python. Experience with Ethereum and other blockchain platforms is essential.
4. Technical Leader
Responsibilities: Oversee the technical direction of the project, mentor team members, and ensure best practices in development. Collaborate with stakeholders to align technical goals with business objectives.
Qualifications: Proven experience in leading development teams, strong problem-solving skills, and a deep understanding of blockchain technologies.
5. Project Manager
Responsibilities: Manage project timelines, resources, and deliverables. Facilitate communication between team members and stakeholders, ensuring that the project stays on track and within budget.
Qualifications: Strong organizational and leadership skills, experience in project management methodologies (Agile, Scrum), and familiarity with the gaming and blockchain industries.
What We Offer
Competitive salaries and benefits
A dynamic and collaborative work environment
Opportunities for professional growth and development
The chance to be part of an innovative project that shapes the future of gaming
How to Apply
If you are passionate about gaming and blockchain technology and are excited to contribute to a groundbreaking project, we would love to hear from you! Please submit your resume and a cover letter detailing your relevant experience and why you would be a great fit for our team.
Join us in creating the next generation of gaming experiences!
A fastest growing Blockchain company is looking to create a decentralized gaming platform that empowers players and developers alike. We are currently seeking to build a talented team to bring their vision to life.
Position Overview
We are looking for skilled professionals to join our development team for a Web3 gaming platform. The ideal candidates will be passionate about blockchain technology and gaming, and possess the expertise to contribute to various aspects of our project. We are hiring for the following roles:
1. Frontend Developers
Responsibilities: Design and implement user interfaces for the gaming platform using modern frameworks (e.g., React, Vue.js). Collaborate with UX/UI designers to create engaging and intuitive user experiences.
Qualifications: Proficiency in HTML, CSS, JavaScript, and relevant frameworks. Experience with Web3 technologies is a plus.
2. Backend Developers
Responsibilities: Develop and maintain server-side logic, database management, and API integration. Ensure the platform's performance, security, and scalability.
Qualifications: Strong knowledge of Node.js, databases (e.g., MongoDB, PostgreSQL), and experience with cloud services. Familiarity with blockchain technology is advantageous.
3. Blockchain Developers
Responsibilities: Design and implement smart contracts, manage blockchain integrations, and ensure the security of decentralized applications. Collaborate with the team to optimize blockchain performance.
Qualifications: Expertise in Solidity, JavaScript, Rust, or Python. Experience with Ethereum and other blockchain platforms is essential.
4. Technical Leader
Responsibilities: Oversee the technical direction of the project, mentor team members, and ensure best practices in development. Collaborate with stakeholders to align technical goals with business objectives.
Qualifications: Proven experience in leading development teams, strong problem-solving skills, and a deep understanding of blockchain technologies.
5. Project Manager
Responsibilities: Manage project timelines, resources, and deliverables. Facilitate communication between team members and stakeholders, ensuring that the project stays on track and within budget.
Qualifications: Strong organizational and leadership skills, experience in project management methodologies (Agile, Scrum), and familiarity with the gaming and blockchain industries.
What We Offer
Competitive salaries and benefits
A dynamic and collaborative work environment
Opportunities for professional growth and development
The chance to be part of an innovative project that shapes the future of gaming
How to Apply
If you are passionate about gaming and blockchain technology and are excited to contribute to a groundbreaking project, we would love to hear from you! Please submit your resume and a cover letter detailing your relevant experience and why you would be a great fit for our team.
Join us in creating the next generation of gaming experiences!