Founding Engineer – Backend / Architecture & AI Systems

About Howie

Howie is an early-stage start up building a vertical AI intelligence platform for the AEC (architecture, engineering & construction) industry. We help enterprise teams find and reuse project knowledge, across documents, drawings, and past decisions, to reduce costly rework during planning and pre-construction and predict the most optimised next step.

Founded by an AEC industry operator with deep Tier-1 relationships across Europe, Howie has direct access to leading architecture and engineering firms. We are already working with six paying co-creation customers across the EU and UK, with a live product in daily use.

We are backed by industry-focused VCs (Pi Labs and DAR).and are preparing for our early seed round. Our focus over the next 12–18 months is turning these collaborations into repeatable enterprise deployments while scaling our technical foundation to support broader adoption.

The Role

We are hiring a Senior Individual Contributor with architectural ownership to design, evolve, and harden the core intelligence infrastructure powering Howie’s enterprise AI platform. This is a hands-on role at the intersection of system design and product iteration. You will shape the backend architecture while working closely with product and applied AI teams to continuously refine how our system ingests, indexes, and retrieves complex project data. Your responsibility is not just to scale what exists, but to clarify boundaries, reduce unnecessary complexity, and introduce scalable patterns without slowing product velocity.

The platform must support enterprise architecture firms operating:

• 5–10 concurrent projects
• 100–200 users per customer
• Thousands of versioned drawings
• Millions of indexed text regions and embeddings

You will architect secure multi-tenant foundations, ensure reliable retrieval performance, and design systems that can grow with customer adoption, balancing long-term integrity with pragmatic iteration. You will help define the technical foundation enabling semantic search, version lineage tracking, spatial reasoning, and cross-project intelligence — under real-world enterprise constraints.

What You’ll Do

🏗 Architect the Core Platform

• Design a scalable multi-tenant backend architecture
• Define data isolation and access control models (project-level, role-based)
• Architect secure indexing strategies across structured, keyword, and vector systems
• Clarify and evolve system boundaries as the product matures, introducing service separation where it adds real leverage

🔎 Build Production-Grade Retrieval Infrastructure designed for real enterprise usage

• Orchestrate hybrid search (PostgreSQL + Elasticsearch + vector database)
• Define query routing strategies across metadata, semantic, and future spatial pipelines
• Design ranking and re-ranking orchestration
• Continuously profile and optimize retrieval performance under increasing concurrency and dataset size

📦 Design High-Throughput Ingestion Pipelines

• Build event-driven ingestion architecture
• Implement async processing queues and backpressure strategies
• Ensure idempotent, fault-tolerant processing
• Plan for large-scale version lineage and revision handling
• Iterate on ingestion strategies as document types, customer workflows, and AI models evolve

🔐 Ensure Multi-Tenant Security & Compliance

• Design and implement tenant isolation patterns across storage and search layers from the ground up
• Design row-level security and query-level filtering guarantees
• Build comprehensive audit logging
• Support enterprise authentication (SSO / Azure AD)

📈 Design System for Scale

• Design and Build systems that scale with customer adoption and increasing dataset complexity.
• 1M+ indexed pages
• 10M+ embeddings
• 100+ concurrent users per tenant
• Define sharding and replication strategies
• Optimize memory usage across search and vector systems
• Build observability (monitoring, tracing, alerting)

♻ Enterprise Reliability

• Introduce structured reliability practices (backup, recovery, monitoring) as customer requirements evolve.

🤝 Technical Leadership

• Contribute to technical roadmap definition and make pragmatic trade-offs between speed and long-term scalability
• Partner with Applied AI engineers building document and spatial models
• Mentor backend engineers
• Set high architectural standards and documentation practices
• Participate in enterprise technical due diligence discussions when needed (investor, customers)

What We’re Looking For

• This role requires balancing architectural rigor with startup velocity. Knowing when not to over-engineer is as important as designing systems that can scale. We’re looking for someone who combines strong systems thinking with pragmatic execution.

Required Experience

• 8+ years of backend engineering experience
• Experience designing and evolving multi-tenant B2B SaaS systems
• Proven track record building systems used in real production environments (enterprise or high-complexity B2B contexts)
• Deep experience with PostgreSQL (schema design, indexing, performance tuning)
• Strong experience with Elasticsearch or OpenSearch
• Experience designing distributed systems and asynchronous processing pipelines
• Solid understanding of reliability, observability, and operational trade-offs
• Experience implementing role-based access control and tenant isolation patterns
• Strong systems design ability (comfortable whiteboarding and reasoning about large architectures)

Technical Strengths

• Data modeling for complex and versioned entities
• API design (REST or similar paradigms)
• Event-driven or async processing architectures
• Search and retrieval infrastructure design
• Performance profiling and bottleneck analysis

Nice to Have (Plus points)

• Experience with vector databases (Qdrant, Pinecone, Weaviate, Milvus, etc.)
• Experience building hybrid retrieval systems (keyword + semantic)
• Knowledge graph or graph database exposure
• Experience with document processing or document intelligence systems
• Familiarity with AEC / construction workflows
• Experience participating in enterprise security or technical due diligence
• Exposure to ML infrastructure or MLOps environments

Why Join

At Howie, you’ll work on real production systems used daily by architects and engineers on complex, high-stakes projects. The problems are technically demanding and directly tied to real-world workflows, not experimental prototypes.

You’ll own critical parts of the platform end-to-end: from architectural decisions and implementation to performance optimization and reliability. Your work will directly influence how enterprise teams access and reuse knowledge across projects.

We’re a small, focused team with short feedback loops and high autonomy. Technical decisions matter immediately, and you’ll collaborate closely with product and applied AI to shape the direction of the system.

This role is intentionally designed as a senior, hands-on builder position with architectural ownership. As Howie scales, there is a clear path toward broader technical leadership for someone who demonstrates:

• Consistent delivery and execution discipline
• Strong architectural judgment and thoughtful trade-offs
• Ability to co-design and evolve the technical roadmap
• Technical depth across system boundaries
• Contribution to shaping and defending Howie’s long-term technical moat
• The ability to set a high technical bar and attract, mentor, and scale exceptional engineering talent

How We Work

We collaborate primarily from a coworking space in Vienna’s 1st district, combining focused in-person work with flexibility across Europe. We value direct communication, shared problem-solving, and building trust through regular interaction, including weekly team lunches and quarterly socials. We’re committed to building a diverse and inclusive team where high standards and mutual respect go hand in hand.