Senior Principal Engineer

Job Description

Complexio is the intelligence layer for enterprise AI. Our platform builds a connected understanding of how businesses actually operate — across people, processes, and systems. 

Enterprises have invested heavily in AI platforms, copilots, and data infrastructure — yet daily work still runs on manual hand-offs and thousands of unseen tasks buried in emails, chats, and spreadsheets. Complexio closes that automation gap. 

Our Event Knowledge Graph ingests structured and unstructured data to create a living map of how an organisation truly works — every task, interaction, and dependency. Our Context Broker unifies this knowledge across enterprise systems in real time, enabling our Orchestration layer and Enterprise Automator to discover, design, and execute workflows autonomously. Stevie, our conversational AI assistant, gives teams a natural way to query and act on that intelligence. 

Complexio deploys securely within your infrastructure and integrates with the enterprise platforms you already run on — turning organisational knowledge into measurable business outcomes. 

A joint venture between Hafnia and Símbolo, backed by leading maritime partners including Marfin Management, C Transport Maritime, Trans Sea Transport, and BW Epic Kosan. Born in maritime, now scaling rapidly across industries. 

We are now onboarding enterprise customers globally, with a platform built to handle the pace and complexity of real business operations. 

Role Purpose 

Complexio's engineering organisation is structured across multiple specialised teams — covering core platform, data structures and the Event Knowledge Graph, the Connections layer, Stevie product, Enterprise Automator, and developer experience. Each team moves fast. The Senior Principal Engineer exists to ensure they move fast in the same direction. 

This is a horizontal leadership role, not a team lead position. You do not own a single product domain — you own the engineering standards, architectural principles, and technical consistency that apply across all of them. You are the person every team can turn to when a decision has cross-cutting implications, and you are the person who notices when two teams are solving the same problem differently and fixes it before it becomes technical debt. 

You will work closely with the Co-CEO (Product & Technology), team leads, and senior engineers across the organisation to define, communicate, and continuously evolve the engineering principles that underpin how Complexio builds software. You will also be a regular presence in the Operational Leadership Team (OLT) — Complexio's cross-functional decision-making backbone — bringing the engineering standards perspective into product, delivery, security, and commercial decisions before they create downstream technical consequences. This is a deeply hands-on role — you are expected to be in the code, in the architecture discussions, and in the design reviews, not operating at a purely strategic remove. 

The right person for this role has seen what happens when fast-growing engineering organisations fragment — inconsistent patterns, duplicated infrastructure, integration friction, security gaps, and compounding maintenance burden — and is motivated to prevent it. You bring the experience, the authority, and the communication skills to set and hold a high bar across the whole engineering function

Requirements

Operational Leadership Team (OLT) Engagement 

•   Participate actively in the OLT — Complexio's cross-functional operating forum spanning Stevie Product, Enterprise Automator, Customer Platform Operations, Core Platform & Data Structures, Connections, Developer Experience, Security, Sales, and Commercial functions 
•   Represent the engineering standards dimension in OLT discussions — surfacing technical implications of product, commercial, and delivery decisions before they are locked in 
•   Ensure that commitments made at OLT level — to customers, to the board, or across teams — are technically feasible and consistent with Complexio's architectural direction 
•   Bring cross-team engineering issues, risks, and blockers to the OLT with clarity and proposed resolution — not just problem statements 
•   Act as the connective tissue between OLT-level strategic decisions and their practical implementation across engineering teams — translating direction into standards and standards into action 

Engineering Principles & Standards 

•   Define, document, and maintain Complexio's engineering principles — the foundational decisions about how we build, structure, test, deploy, and operate software across all teams 
•   Establish and govern coding standards, design patterns, and architectural conventions that apply platform-wide — ensuring consistency without stifling team autonomy 
•   Own the technical standards backlog — identifying where standards are absent, contradictory, or outdated, and driving resolution with the relevant teams 
•   Ensure standards are practical, well-reasoned, and adopted — not just written down; you are accountable for the gap between documentation and reality 

Cross-Team Architecture & Design 

•   Serve as the senior architectural authority across all engineering teams — providing input, challenge, and guidance on decisions with cross-cutting implications 
•   Lead or co-lead architectural design reviews for significant new capabilities, integrations, or platform changes — ensuring decisions are consistent with Complexio's long-term technical direction 
•   Identify and resolve architectural conflicts, duplication, and inconsistency across teams before they compound into larger structural problems 
•   Maintain a living view of Complexio's overall system architecture — ensuring it remains accurate, accessible, and useful to engineers across the organisation 
•   Define and govern integration patterns between Complexio's core components: EKG, Context Broker, Orchestration layer, Enterprise Automator, Stevie, and the Connections layer 

Technical Governance & Decision Making 

•   Own Complexio's Architecture Decision Record (ADR) process — ensuring significant technical decisions are documented, reasoned, and accessible across the engineering organisation 
•   Chair or actively participate in cross-team technical forums, design reviews, and engineering guilds 
•   Define escalation criteria for architectural decisions — what can be decided at team level, what requires cross-team alignment, and what requires principal engineer sign-off 
•   Provide a decisive, well-reasoned position when teams are blocked by conflicting approaches or unresolved design questions 
•   Act as the final technical review point for decisions with significant security, scalability, or inter-system integration implications 

Platform Quality & Engineering Health 

•   Define and track engineering health metrics across the organisation — including test coverage standards, incident rates, deployment frequency, build stability, and technical debt ratios 
•   Identify systemic quality issues that span multiple teams and drive coordinated remediation 
•   Establish and evolve Complexio's standards for observability, logging, alerting, and incident response — ensuring every team is operating to a consistent and appropriate level of operational maturity 
•   Champion a culture of code review rigour — setting expectations for what good review looks like and supporting teams to meet that bar 
•   Own and evolve Complexio's approach to automated testing — unit, integration, end-to-end, and performance — across the full platform 

Security & Compliance Engineering 

•   Ensure security principles are embedded into Complexio's engineering standards — not bolted on after the fact 
•   Define and govern security-relevant patterns across the platform: authentication, authorisation, RBAC, data encryption at rest and in transit, secrets management, and audit logging 
•   Work with the Head of Security and Solutions Consultant to ensure that the platform's security architecture can be accurately and confidently represented to enterprise customers in due diligence processes 
•   Identify and remediate security anti-patterns across the codebase through systematic review and standards enforcement 
•   Ensure Complexio's deployment architecture — including customer-hosted and Complexio-managed environments — is consistent with documented security standards and enterprise compliance requirements 

Developer Experience & Knowledge Sharing 

•   Own the internal engineering knowledge base — ensuring that standards, patterns, ADRs, and architectural documentation are maintained, findable, and actually used 
•   Run regular cross-team engineering forums — creating structured opportunities for teams to share learnings, surface conflicts, and align on direction 
•   Identify repeated friction points in the developer experience and work with the DevEx team to address them systematically 
•   Mentor senior engineers across the organisation — raising the overall technical bar through hands-on code review, design guidance, and direct coaching 
•   Produce clear, accessible technical writing — standards documents, design guides, and architecture references — that engineers at all levels can act on 

Hands-On Engineering Contribution 

•   Remain an active, hands-on contributor to the codebase — particularly on foundational, cross-cutting components where your decisions will set the pattern for other teams to follow 
•   Prototype and validate architectural approaches before they are adopted platform-wide — proving decisions in code, not just in diagrams 
•   Conduct deep technical investigations into persistent or systemic issues — providing root cause analysis and remediation plans that address the underlying pattern, not just the immediate symptom 
•   Set the technical example: your code, your reviews, and your design discussions define the standard others are expected to reach 

What We're Looking For 

Essential 

•   12+ years of professional software engineering experience, with a substantial portion in senior, staff, or principal engineer roles with cross-team scope 
•   Demonstrable experience defining and enforcing engineering standards, architectural principles, or technical governance across multiple teams or products 
•   Deep expertise in distributed systems design — event-driven architectures, graph data models, API design, microservices, and data pipeline patterns 
•   Strong command of at least one primary backend language (Python, Go, Java, or equivalent) and broad familiarity across the stack 
•   Hands-on experience with cloud-native infrastructure — containerisation (Docker, Kubernetes), CI/CD pipelines, infrastructure as code, and cloud platforms (AWS, Azure, or GCP) 
•   A proven ability to make and communicate clear, well-reasoned architectural decisions under uncertainty — and to bring teams along with you 
•   Experience with security engineering principles: authentication and authorisation patterns, secrets management, encryption, and enterprise compliance requirements 
•   Strong technical writing — able to produce standards documents, ADRs, and architecture guides that are clear, durable, and actually adopted 

Desirable 

•   Experience with knowledge graphs, graph databases (Neo4j or equivalent), or event sourcing architectures 
•   Familiarity with LLM integration patterns — prompt engineering, retrieval-augmented generation (RAG), context management, and AI safety in enterprise environments 
•   Experience in a scale-up or growth-stage technology company where engineering standards had to be built from a low base, not inherited from an established organisation 
•   Background in enterprise software deployment models — customer-hosted, hybrid, and multi-tenant SaaS — and the architectural implications of each 
•   Experience establishing or leading engineering guilds, communities of practice, or internal technical forums 

Who You Are 

•   A systems thinker — you instinctively look for patterns, inconsistencies, and second-order effects across a complex engineering organisation; you see the whole board, not just your piece of it 
•   Hands-on and grounded — you are not an ivory tower architect; you write code, you do reviews, and you earn your technical authority through demonstrated craft, not seniority alone 
•   Decisive and clear — when teams need a direction, you give them one; you don't produce endless caveats and you don't leave decisions in the air 
•   A strong communicator — you can write a standards document that engineers actually read, run a design review that produces a decision, and explain a complex architectural trade-off to a non-technical stakeholder without losing accuracy 
•   Low ego and collaborative — you hold a high bar, you push back when you need to, but you bring teams with you rather than imposing standards from above 
•   Motivated by leverage — you are energised by the fact that the right decision, made once and communicated well, improves the work of every engineer across the organisation 
•   Comfortable with ambiguity — Complexio is a fast-moving company; not everything has a clear answer yet, and you are the person who creates clarity rather than waiting for it 

Benefits

• A rare opportunity to shape the engineering culture and technical foundations of a fast-growing enterprise AI company from an early stage 
•   Horizontal influence across the entire engineering organisation — your decisions matter at scale 
•   Competitive senior compensation with equity participation aligned to Complexio's growth trajectory 
•   Direct access to Co-CEO product and technology leadership — decisions move fast and your input will be acted on 
•   A technically ambitious environment: the problems are genuinely hard, the platform is genuinely differentiated, and the engineering team is genuinely capable 
•   Remote-first working with a high-trust, low-bureaucracy culture