IaaS Software Architecture

Project duration: February 2026 – at least Mai 2026 (as always client aims for long term assignments)

Seniority: Senior

Volume: Full-Time

Location: Remote & Frankfurt am Main, up to 50% onsite possible

General Description

The design and evolution of the Infrastructure-as-a-Service (IaaS) platform requires a clear architectural vision and a joint approach to defining the software architecture across core infrastructure components. This includes developing scalable platform services, robust infrastructure APIs, distributed systems, and orchestrated service layers that support modern, software-defined infrastructure delivery.

Key architectural goals focus on:

• Enabling microservice-based designs for modular and scalable infrastructure automation.

• Promoting resilient, observable, and secure service patterns aligned with long-term product and platform strategies.

• Establishing API-first principles to support self-service, automation, and integration across infrastructure layers.

• Utilizing graph-based models to capture and manage complex resource relationships.

Architecture efforts are in line with stakeholders across engineering, product management, and platform sponsor to ensure that technical decisions support the broader strategy. Coordination ensures platform components remain maintainable, extensible, and optimized for scalability and operational efficiency. Ongoing architectural initiatives are steered in coordination with platform leadership to ensure technical alignment, consistency, and innovation across the IaaS domain.

Objective: Ownership and define software architecture for core IaaS components

Tasks:

• Providing designs of architecture for infrastructure orchestration layers and distributed microservices.

• Definition of APIs based on FastAPI and ensure consistency across REST interfaces.

• Integration of asynchronous processing via messaging systems like Celery and RabbitMQ.

• Incorporation of event-driven communication through Kafka.

• Establishing of service discovery patterns compatible with dynamic IaaS workloads.

• Implementation of scalable, secure, and observable service patterns aligned with platform targets.

• Translate domain models into Pydantic-based schemas for use in modern Python frameworks.

Objective: Drive strategic architectural initiatives

Tasks:

• Co-development of a microservices architecture supporting IaaS provisioning workflows with graph-based dependency

resolution and asynchronous processing.

• Contributing to the platform architecture roadmap, including enabler identification and risk assessment.

• Evaluation of short- and mid-term architectural priorities in line with product strategy.

Objective: Ensure architectural cohesion across development

Tasks:

• Coordination with Product Management, Delivery units, and peer architects to align design efforts.

• Consulting in cross-functional architectural reviews and design councils.

• Act as primary architectural contact for engineering groups; provide structured design input and technical mentoring.

Objective: Maintain technical consistency and software quality

Tasks:

• Definition of architectural guardrails for observability, authentication/authorization (e.g., OAuth2, IAM), and

operational resilience.

• Reviewing technical designs for adherence to clean architecture and reusability principles.

• Guiding of engineering decisions during all development phases to safeguard architectural integrity.

Objective: Proactively manage architecture-related deliverables

Tasks:

• Organization of architectural efforts based on technical complexity, interdependencies, and expected business value.

• Communication of the progress and raise blockers early to relevant stakeholders.

• Gathering of missing context independently and resolve design uncertainties within the expected project cadence.

Must-have experience

o Deep expertise in:

o Python (modern idioms, best practices)

o REST API development with FastAPI

o Asynchronous processing frameworks (e.g., Celery, RabbitMQ)

o Graph modeling and ArangoDB or similar graph databases

o Pydantic-based data modeling

o Microservices architecture and distributed systems design

o 7–10 years in software architecture or infrastructure platform engineering.

o Strong Python software engineering skills (FastAPI, Pydantic, Celery).

o In-depth Experience in Modular/Distributed Software as well as Highly Available Systems Architecture.

o In-depth Experience in Microservices and distributed system design (synchronization, replication, consensus etc.).

o Experience in Data Modelling (relational, document, graph).

o Experience in REST API design.

o Experience in AuthN/AuthZ (e.g. IAM/RBAC/OAuth/OIDC etc.)

o Experience in designing Message Brokers (async/sync patterns).

o Experience with Service Discovery patterns and systems.

o Solid understanding of K8s concepts (namespaces, services, deployments, ingress) and surrounding technologies (e.g.

service mesh).

o Understanding of Observability concepts (logs, metrics, traces etc.).

o Experience in

o Software architecture patterns (DDD, event-driven design)

o Authentication/Authorization (e.g. IAM/RBAC/OAuth/OIDC etc.)

o Observability principles (logs, metrics, tracing with tools like Prometheus, Grafana, OpenTelemetry)

o Experience in working in technical software teams and designing microservice-based systems in production.

o Expertise in building scalable backend systems in an Agile/DevOps environment.

Must-have language skills:

o Fluent English in speech and writing (at least C1).

Preferred experience

o Certifications in architecture, cloud infrastructure, or security (e.g. TOGAF, AWS/Azure/GCP certifications) are an

advantage.

o Understanding of Observability tools (Prometheus, Grafana, OpenTelemetry).

o Exposure to infrastructure platforms, IaaS service delivery, and API-first platform design.