Senior Full-Stack Engineer (Frontend-focused, AI-first) / Senior Backend Engineer

About the role

Utorg provides infrastructure for stablecoin payments and has a significant user base, while Zerion is a Web3 provider with a large number of active wallets and API clients. Both companies are focused on leveraging cutting-edge technologies to enhance their services.

The Senior Full-Stack Engineer at Utorg will be responsible for end-to-end feature ownership, including UI and backend changes, while also building AI-driven workflows. The Senior Backend Engineer at Zerion will develop scalable distributed systems and work directly with API clients to fulfill their requests.

The salary ranges from $80,000 to $150,000 depending on the specific role and experience.

Skills that matter here

• React: This role requires strong experience with React to build user interfaces.
• TypeScript: TypeScript is essential for developing robust applications in this position.
• Java: Java is preferred for backend development, especially with Spring Boot.
• PostgreSQL: Experience with PostgreSQL is necessary for designing and managing database schemas.
• AI tools: Candidates will utilize AI tools in their daily workflows, affecting both frontend and backend processes.
• Docker: Docker is used for containerization, ensuring consistency across development and production environments.

Who this role suits

• A candidate with over five years of experience in software development, particularly in frontend or backend roles.
• Someone comfortable in a fast-paced startup environment who values clear communication and ownership of their work.
• A pragmatic problem-solver who understands the implications of using AI in software development.
• An individual who can navigate legacy codebases and is security-minded in their approach to coding.

From the employer

Senior Full-Stack Engineer (Utorg)

• Ownership of end-to-end features (UI, API contract, backend changes, tests, release, monitoring)
• Architectural decisions, migrations (legacy admin → new stack)
• Building AI-driven workflows (context files, skills, commands, AI review in CI, agent e2e/visual checks)
• Code reviews (including agents).

Senior Backend Engineer (Zerion)

• Development and support of scalable distributed systems
• Ownership of services end-to-end (architecture, implementation, monitoring, reliability)
• Working with API clients (turning vague requests into concrete proposals)
• Developing Web3 components (protocol integrations, supporting new networks, interacting with smart contracts)
• Ensuring quality, performance, and security, using AI in daily workflow.

Senior Full-Stack Engineer (Utorg)

• 5+ years of commercial frontend development experience, 3+ years with React + TypeScript in production
• Experience with large legacy codebases, production backend experience in any language (Java/Kotlin + Spring preferred)
• Designing REST APIs, PostgreSQL (schema, indexes, migrations)
• Daily work with agents (Claude Code, Codex)
• Understanding failure modes (fake APIs, scope creep, 'fixing' tests instead of code, secret leaks, prompt injection)
• Playwright/Vitest, security-minded, fluent Russian, English for reading/writing.

Senior Backend Engineer (Zerion)

• 5+ years of designing and building distributed backend systems
• Strong knowledge of algorithms and data structures
• Comfort in a fast-paced startup environment, desire to impact the product
• Direct contact with clients, daily use of AI (understanding where it changes the approach and where it cannot be trusted)
• High coding standards, ownership, clear communication, pragmatism, quick learning.

Senior Full-Stack Engineer (Utorg)

• Salary: ~$80,000 – $100,000 per year (gross) (estimate).

Senior Backend Engineer (Zerion)

• Salary: ~$110,000 – $150,000 per year (gross) + options (estimate).