Principal Backend Architect

Principal Backend Architect / Engineer (C#/.NET, Azure)

International job opportunity

USD 50/hr - Direct Hire
Remote — Brazil
Long-term, full-time

Required

English – Advanced (written and spoken, customer-facing)
20+ Years Backend Engineering
15+ Years C# / .NET
8+ Years Microsoft Azure (Functions, Service Bus, Data Factory)
5+ Years Architecture or Technical Leadership
Daily hands-on use of Agentic AI tooling — HARD REQUIREMENT

About the AI requirement: this is not "I have used ChatGPT". The client expects
daily, hands-on work with agentic tooling such as Claude, Claude Code or equivalent,
plus real experience building with AI: agents, reusable skills, MCP servers and
evaluations. Candidates without this will not move forward.

Deep expertise in C#/.NET across secure, scalable and resilient commercial backend
systems.

Hands-on Azure: Functions, Service Bus and Data Factory, plus PostgreSQL, Cosmos DB
and Snowflake, with solid CI/CD and DevOps practice.

Proven experience breaking down a large monolith incrementally, favouring safe and
reversible steps over rewrites.

Strong background in event-driven and asynchronous architecture: ordering,
idempotency, poison messages and dead-lettering.

Solid API and contract design experience, including versioning and backwards
compatibility for internal teams, front-end and external integrators.

Strong instincts for data access at scale: query performance, zero-downtime
migrations and messy customer data.

Production ownership: observability, alerting, incident response and root-cause
analysis.

Nice to Have

Experience partnering with dedicated Data and UI architects inside an established
architecture function.

Experience designing customer and partner integrations where failures are visible
and recoverable.

Track record of raising the AI capability of an engineering team, not just your own.

Experience writing Architecture Decision Records and running technical office hours.

Description / Responsibilities:

What They'll Do

Our client is a US-based software company with an engineering team of around 30
people, working across a large monolith and a growing set of microservices. They
already have dedicated architects for front-end and data, and they are now looking
for someone to own the backend: the largest and most business-critical part of the
platform.

• Own the backend architecture across all products and drive the incremental decomposition of the monolith into well-bounded services
• Set and enforce backend standards, best practices and tooling, and build shared platform capabilities (libraries, service templates, cross-cutting concerns)
• Own API and contract design, including versioning and backwards compatibility
• Own event-driven architecture on Azure Service Bus: delivery guarantees, retries, idempotency and failure handling
• Define how customer and partner integrations are built so failures are visible and recoverable
• Partner with the Data Architect on service data ownership, transactional boundaries, access patterns and query performance
• Improve reliability, security, observability and cloud cost efficiency
• Lead by example with AI-assisted engineering and help raise the AI capability of the wider team
• Mentor engineers, review key pull requests, run office hours and write Architecture Decision Records
• Participate in incident response, technical interviews, quarterly planning and occasional customer conversations

What We're Looking For:

This is a senior individual contributor role. No direct reports, and you will keep
writing code. You will report to the Lead/Principal Architect and work side by side
with the Principal UI Architect and the Data Architect.

We are looking for a principal-level engineer who has already carried the weight of
a business-critical backend: someone who has broken a monolith apart without
breaking the business, who knows why a message ended up in the dead-letter queue at
2am, and who can defend an architecture decision to both an engineer and a customer.

You will have real ownership over the most critical part of the platform, a seat at
the architecture table, and the chance to shape how a growing team builds, including
how it uses AI day-to-day.

The client is highly selective. We are shortlisting a small number of top-tier
profiles only.