Backend Engineer

• Build, refine, and maintain core features across the full stack, ensuring a polished, high-performance user experience;
• Develop and optimize both the company's main application and internal Admin Interfaces (including user management and billing systems);
• Implement high-fidelity UI/UX, ensuring pixel-perfect execution of product designs down to the smallest detail;
• Work closely with Product Managers and Designers, translating Figma designs into seamless production code;
• Collaborate closely with an additional developer and the QA team to ensure smooth integration, high code quality, and flawless deployment;
• Design and maintain significant, sensitive, and secure back-end logic and infrastructure;
• Take responsibility for maintaining and updating the company’s marketing website, built on WordPress;
• Leverage AI tools effectively to accelerate the development lifecycle and optimize delivery speed without compromising quality.

Full-Stack Developer, Python/Java/React

• Design, build, and maintain Python services for sports data ingestion, transformation, and distribution
• Integrate with third-party sports data providers and handle differences between provider models, formats, and update patterns
• Build reliable pipelines for near real-time and batch data processing
• Improve data validation, reconciliation, monitoring, alerting, and replay tooling
• Work on domain models for events, competitions, participants, markets, odds, scores, and related sports entities
• Investigate production issues, trace data problems, and improve system observability
• Collaborate with backend, product, trading, QA, and platform teams to deliver dependable data flows
• Contribute to architecture decisions, code reviews, technical standards, and mentoring within the squad

Senior Python Engineer, DataFeed Team

Full-stack Engineer

• Architect End-to-End Workflow Systems
• Own, build, and iterate on the Workflow Builder across the entire stack
• Drive system design, data modeling, and API contracts
• Participate in cross-functional architectural discussions
• Advance our Front-End Architecture
• Build production-grade visual features using React (v18+)
• Integrate and extend modern component libraries (e.g., MUI, Radix UI, Shadcn/ui)
• Build Scalable and Secure Back-End Services
• Develop high-availability, secure back-end services and microservices
• Design, implement, and maintain highly performant REST or GraphQL APIs
• Define and uphold coding standards
• Deliver High Quality at Scale
• Monitor and optimize full-stack performance metrics
• Write comprehensive test suites
• Partner closely with UX designers and Product Managers
• Mentor & Lead
• Serve as a technical mentor for junior and mid-level engineers
• Contribute to technical roadmap planning
• Strategically Apply AI Tools
• Champion the use of AI-assisted development tools
• Build and evaluate AI-powered features

Senior Software Engineer I, Remote Eligible

Android Engineer

• **Key Responsibilities**
• - Design, develop, test, and maintain scalable Android applications.
• - Lead technical design, architecture discussions, and technical decision-making for Android applications while contributing to cross-platform architecture across mobile and web.
• - Collaborate with Product Managers, UX/UI Designers, and fellow engineers to define and implement new features.
• - Contribute to the development and maintenance of Angular-based web applications.
• - Perform code reviews, provide constructive feedback, and promote engineering best practices to ensure high code quality, maintainability, and technical excellence.
• - Troubleshoot, debug, and resolve performance, scalability, and reliability issues while ensuring application quality through unit testing, integration testing, and continuous improvement practices.
• - Stay up to date with emerging technologies, frameworks, and industry trends.
• - Mentor junior developers and contribute to a collaborative, knowledge-sharing engineering culture.

Senior Android Developer

• Collaborate closely with the customer to understand functional and non-functional software requirements for the system
• Analyze functional and non-functional requirements, prepare the design of the system according to these requirements, and monitor solutions to match them afterward
• Guide and assist the development team and provide them with architectural blueprints to follow
• Communicate and collaborate across teams to define optimal technical solutions
• Explore a range of technology and design possibilities and alternatives to improve system implementation

Software Architect, .NET – B2B or Standard Contract

• Build and maintain modern web applications using TypeScript and React.
• Develop new product features and improve existing applications.
• Integrate third-party APIs and external services.
• Build internal tools and automations that improve business processes.
• Translate business requirements into reliable, maintainable software.
• Write clean, well-structured, and maintainable code.
• Troubleshoot issues and continuously improve application performance and reliability.
• Participate in code reviews and collaborate with teammates to improve engineering practices.
• Communicate progress, blockers, and technical decisions clearly with the team.

Software Developer

• Design, develop, and maintain high-quality .NET applications
• Collaborate with cross-functional teams to define, design, and ship new features
• Write clean, scalable, and testable code following best practices
• Optimize application performance, security, and scalability
• Troubleshoot, debug, and resolve technical issues
• Stay current with emerging technologies and propose improvements to existing solutions

.Net Developer

• Design and build robust backend services that orchestrate Knowledge Graphs, LLMs, and custom ML models
• Implement scalable APIs and integration layers that connect AI components with enterprise systems
• Develop retrieval and context architectures, including RAG and GraphRAG patterns
• Contribute to the design of distributed, production-grade systems for demanding enterprise workloads
• Help shape how Knowledge Graphs interplay with modern AI in real-world deployments
• Collaborate with ML engineers, data engineers, and solution architects to deliver end-to-end functionality
• Collaborate with technical and business stakeholders to solve complex information challenges
• Explore and adopt modern AI, NLP, and backend engineering technologies.

Java Backend Engineer – AI Platforms

• Join a Remote-First, AI-augmented engineering organization
• Build and maintain backend services, APIs, data persistence, and frontend interfaces
• Work in small increments, integrate frequently
• Co-own data modelling decisions with your team
• Write automated tests as a first-class deliverable
• Deploy and operate software as a team
• Document design decisions and communicate proactively
• Pair with teammates regularly and share effective patterns and tools
• Code review as a team practice

Senior Software Engineer

Frontend Engineer

• Be a key player at the forefront of the digital assets movement, propelling your career to new heights!
• Join a dynamic and rapidly expanding company that values and rewards talent, initiative, and creativity.
• Work alongside one of the most brilliant teams in the industry.
• Our Engineering team plays a pivotal role in ensuring the robustness, speed, and security of our Product.
• Dedicated to enhancing performance, providing a best-in-class user experience, ensuring compliance, and safeguarding data.
• Seeking a skilled Frontend Software Engineer whose ambitions match ours: to skyrocket technical skills to architect-level mastery.
• Grow your technological understanding and expertise, focusing on areas that make us industry leaders: performance, launch time efficiency, system resilience, and the utmost data confidentiality.

Software Engineer, Angular

• Define and evolve architectural solutions that improve system performance, scalability, reliability, and operational excellence
• Design and refine frameworks, tooling, and engineering standards that enhance system resilience and longterm maintainability
• Partner closely with Product, Infrastructure, and Platform teams to embed sound architectural principles into planning, design, and delivery
• Contribute hands-on to critical initiatives, including prototypes, proof-of-concepts, and production systems that demonstrate scalable, maintainable design
• Guide teams in adopting robust distributed system patterns, ensuring fault tolerance, observability, and operational maturity are built in from day one
• Provide thoughtful design reviews and technical guidance that raise the bar for engineering quality and consistency
• Collaborate with engineering leaders to align architectural decisions with business priorities and long-term platform strategy

Software Architect

• Define and evolve architectural solutions that improve system performance, scalability, reliability, and operational excellence.
• Design and refine frameworks, tooling, and engineering standards that enhance system resilience and longterm maintainability.
• Partner closely with Product, Infrastructure, and Platform teams to embed sound architectural principles into planning, design, and delivery.
• Contribute hands-on to critical initiatives, including prototypes, proof-of-concepts, and production systems that demonstrate scalable, maintainable design.
• Guide teams in adopting robust distributed system patterns, ensuring fault tolerance, observability, and operational maturity are built in from day one.
• Provide thoughtful design reviews and technical guidance that raise the bar for engineering quality and consistency.
• Collaborate with engineering leaders to align architectural decisions with business priorities and long-term platform strategy.

• You will work closely with the Senior MarTech Operations Manager to build and manage tools and solutions that reduce cost to serve and increase speed to market.
• You will help review workflows and processes to identify opportunities to improve and automate.
• You will use your excellent problem-solving skills to creatively find solutions.
• You'll also develop HTML and CSS for customer-facing digital assets including websites, emails, and banners, ensuring both technical excellence and visual consistency.

Frontend Engineer – React

• Working in an Agile environment, where team work is always recognized and appreciated.
• Design, develop and unit test solutions of any size or complexity
• Produce clean code
• Become part of a fast-moving team where quality always comes first
• Understand all of Fourth’s products in detail, how they are integrated with each other, and their business value
• Diagnose defects and provide effective solutions.
• Provide development estimates, be a part of planning sessions
• Understand and support the release management process

Junior .NET Developer

• Design, build, and maintain scalable backend services and APIs powering our e-commerce workflows, ensuring consistency, performance, and correctness.
• Design, build, and maintain end-to-end product features spanning across multiple services.
• Collaborate with Product Managers, UX Designers, and engineers to translate business requirements into robust technical solutions.
• Debug and resolve production issues across services and multiple levels of the stack.
• Review peer code to ensure correctness, performance, maintainability, and knowledge sharing.
• Write unit and integration tests and collaborate with QA engineers responsible for API and end-to-end test coverage.
• Continuously improve engineering standards, tooling, and processes.
• Mentor and support junior engineers on backend fundamentals and system design.
• Contribute to scalable, reliable, and maintainable system architecture.

Senior Full Stack Developer

Software Engineer

• Plays critical role in evolving and modernizing our UKG platform across a complex, global enterprise
• Design, build, and optimize scalable solutions that support thousands of employees worldwide
• Deliver high-impact outcomes across timekeeping, scheduling, and integrations
• Helps drive our transition from a project-based to a product-based operating model
• Builds, maintains, integrates and implements software applications within the organization
• Performs complex software application testing, quality assurance, configuration, installation and support to ensure smooth, stable and timely implementation

Senior UKG Pro Workforce Management Developer

• Work alongside engineers, product owners and stakeholders to ensure quality software delivery
• Be a key component of a cross-functional team
• Interact with product owners and stakeholders
• Contribute to technical discussions
• Help deliver on the technical strategy and tactical implementation

Mid/Senior Android Engineer

iOS Engineer

• Work alongside our other engineers, product owners and stakeholders to ensure what we build is best in class
• Be a key component of a cross-functional team delivering quality software
• Interact with product owners and stakeholders, contribute to the technical conversations
• Report to a Principal Engineer and help deliver on the technical strategy and tactical implementation
• Support existing, and develop new, features to support business needs across all Sun
• Help define requirements and create tickets
• Assist with the release process to deploy new features/fixes to production
• Leverage AI to boost productivity

Mid/Senior iOS Engineer

• Review Requests for Proposal (RFPs) to identify required information for proposal text and budget development; collaborate closely with the business development team to prepare and finalize submissions
• Develop proposal narratives and cost budgets for new proposals, re‑bids, change orders, and related documents in alignment with defined scope of work
• Provide support and assistance to other Proposal Developers in the delivery of assigned business opportunities, as needed
• Revise or develop preliminary agreements and related budgets; ensure scope of work is clearly defined and budgets accurately reflect the agreed scope
• Develop and maintain an understanding of, and compliance with, all processes, policies, and guidelines relating to proposal development
• Participate in strategic discussions and calls to clarify customer requirements and identify any inconsistencies or gaps in customer‑provided information
• Perform quality control reviews and edits on proposal documents to ensure accuracy, consistency, and adherence to company standards
• Support the finalization and distribution of proposal documents to customers and relevant internal departments
• Update and maintain corporate systems and databases; ensure accurate and timely information is reflected in tracking and reporting tools
• Participate in customer meetings where required to support proposal development activities
• Contribute to departmental and process improvement initiatives
• Perform other duties as assigned

Proposal Developer I

• Provide deep technical expertise in backend development, code reviews, and architectural discussions, ensuring best practices are followed
• Design, develop, test, and deploy backend software solutions using Node.js and Java, adhering to high-quality standards
• Architect and optimize relational database schemas, write efficient queries, and ensure data integrity and performance
• Develop and maintain components for real-time communication, including SIP signaling and RTP streaming
• Explore and implement solutions for audio/video media processing and integration within the contact center environment
• Contribute to the development of contact center-specific features and integrations, understanding the nuances of the domain
• Identify and address performance bottlenecks, ensuring the platform can scale to meet growing demands
• Diagnose and resolve complex production issues, providing timely and effective solutions
• Work closely with product managers, architects, QA engineers, and other stakeholders to deliver high-quality software

Software Engineer jobs in Bulgaria

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Full-Stack Developer, Python/Java/React

Senior Python Engineer, DataFeed Team

Senior Software Engineer I, Remote Eligible

Senior Android Developer

Software Architect, .NET – B2B or Standard Contract

Software Developer

.Net Developer

Java Backend Engineer – AI Platforms

Senior Software Engineer

Software Engineer, Angular

Software Architect

Software Architect

Frontend Engineer – React

Junior .NET Developer

Senior Full Stack Developer

Senior UKG Pro Workforce Management Developer

Mid/Senior Android Engineer

Mid/Senior iOS Engineer

Proposal Developer I

Senior Backend Software Engineer, Node.js, Java