Senior Backend Engineer

About Pebbles Ai
Pebbles Ai is building the most advanced Go-To-Market Operating System (GTMOS™️) for B2B teams, powered by Neurosymbolic AI purpose-built for GTM workflows.
We are an AI-native product company built between Lviv and London, combining world-class engineering with strong commercial acumen.
We have a beautiful office in the heart of Lviv, and a shared space within the Google offices in the City of London.
Our long-term ambition is to build a category-defining Anglo-Ukrainian technology company and reach an IPO by 2031, following the path of companies like Grammarly, MacPaw, and GitLab.
Despite being founded in 2023, Pebbles Ai has already earned strong external credibility. Our technology has been featured by Forbes Innovation, TechRadar, Tech.eu, and other major publications for our work in Neurosymbolic AI.
We are backed by Google for Startups AI (London) and accelerated by Mountainside Ventures, where only the top 3% of later-stage startups are accepted.

Why Now?
The hardest part of an early-stage startup is already behind us.
The product exists.
The AI engine exists.
The foundations are built.
Early revenue is live.
Now we are entering a phase where backend excellence, architectural clarity, and disciplined execution matter more than experimentation.
We are looking for a Senior Backend Engineer who wants to grow into a Head of Engineering role by taking real ownership of backend systems, delivery quality, and technical decision-making over time.
This is a career-defining opportunity for someone who wants to move beyond tickets and features and start owning outcomes.

Role Summary
This role starts as a Senior Backend Engineer with extended ownership, and evolves into a Head of Engineering role as scope, impact, and leadership grow.
From day one, you will be deeply involved in:
— Backend architecture
— Platform stability
— Delivery quality
— Cross-team technical alignment
As you demonstrate ownership, judgment, and execution strength, you will progressively take on:
— Broader system ownership
— Technical leadership responsibilities
— Team coordination and mentoring
— Engineering roadmap influence
This is a responsibility-first growth path, earned through impact, not title inflation.

Initial Focus (First 6–12 Months)
— 80% hands-on backend execution
— 15% architectural & technical decision-making
— 5% mentorship & emerging leadership
As you grow into the Head of Engineering mandate, this balance will gradually shift.

What You’ll Do From Day One
Backend Engineering & Delivery
— Build and maintain core backend services in Java Spring Boot
— Take ownership of backend features from design to production
— Write clean, testable, production-grade code
— Review pull requests and contribute to code quality standards
— Improve system reliability, performance, and observability
— Actively participate in on-call, debugging, and incident resolution

Architecture & Platform Foundations
— Contribute to backend and platform architecture decisions
— Help define system boundaries and scaling strategies
— Work with modular monolith and microservices pragmatically
— Participate in decisions around infrastructure, data flows, and integrations
— Develop a strong intuition for cost vs performance trade-offs
— Keep the platform secure, observable, and maintainable

AI Platform Integration (Production-Focused)
— Integrate AI-native features into the backend platform
— Understand how multi-agent systems and agentic workflows operate in production
— Collaborate closely with the AI team to connect AI capabilities with backend systems
— Ensure AI features are reliable, explainable, and tied to real business value
— Focus on practical, customer-facing AI, not research for its own sake

Cross-Functional Collaboration
— Work closely with Product, Frontend, AI, and Commercial teams
— Support customer-facing integrations and implementations
— Help translate product and business requirements into technical solutions
— Communicate technical decisions clearly to non-technical teammates
— Gradually take on a coordination role between backend and other functions

Growth Path to Head of Engineering
As you demonstrate:
— Strong delivery ownership
— Architectural judgment
— Reliability under pressure
— Clear communication
— Ability to mentor others

You will progressively grow into:
— Backend ownership across the platform
— Technical leadership across teams
— Engineering planning and prioritization
— A future Head of Engineering role with expanded mandate

What Experience Do You Need?
Must Have
— 6+ years of backend engineering experience with Java and Spring Boot
— Strong understanding of both relational (RDBMS) and non-relational databases
— Hands-on experience with PostgreSQL and MySQL
— Experience with Docker, Kubernetes, Gradle, Jib, and GitHub Actions
— Practical experience with GCP and GKE; certification in a major cloud provider (AWS or GCP, Azure)
— Experience integrating with payment providers like Stripe, Paddle, Zipco, Affirm, Lemon Squeezy etc.
— Experience with monitoring and observability tools such as Sentry, Prometheus, and Spring Actuator
— Ability to confidently read, debug, and ship production-ready code
— Proven problem-solving skills, knowledge of Complexity Theory
— Ownership mindset and high personal accountability
— Low-ego, collaborative attitude with the ability to handle constructive conflict
— Motivation to build something meaningful and long-term
— Clear communication skills and Upper intermediate(B2) English (written and spoken)

Nice to Have
— Experience with AI-native or LLM-powered products
— Startup or scale-up experience
— Exposure to structured and unstructured data pipelines
— Familiarity with vector databases, embeddings, or retrieval systems
— Understanding how popular FE frameworks work or experience with them (React.js, Angular or Vue.js)
— Background in B2B SaaS, productivity tools, CRM, RevOps, or Future of Work

Is This Role for You?
This role is ideal if you:
— Are a senior backend engineer ready for real ownership
— Want to grow into engineering leadership, not just stay an IC forever
— Enjoy building complex systems that ship and scale
— Want your work to have visible impact on users and the company
— Care about legacy, craft, and long-term value
— Are excited by building cutting-edge AI-native products
— Want to work closely with founders and influence company-level decisions

Compensation
— Competitive salary aligned with early-stage AI startups
— Equity / shares participation tied to long-term value creation
— Clear growth path in responsibility, scope, and compensation
— Mentorship from senior technical and commercial leaders
— A high-trust, low-ego team of genuinely strong builders