Software Architect

OEC; Polska; On-site; PLN 544,000 - 700,000; Full time

Job summary

OEC is seeking a senior architecture-focused software engineer to define and enforce module boundaries within a modular backend ecosystem. You will drive ADRs, author playbooks for AI agents, and guide adoption of a shared library across eventing, mediation, auditing and observability.

You will mentor engineers on platform conventions and oversee domain-pack extensibility. You will partner with tech leadership and product management on roadmaps, ensuring scalable, secure and testable integration

Qualifications

• 7+ years building software with modular or service-oriented backends and enforcing boundaries.
• Strong .NET/C#, ASP.NET Core, EF Core, with cross-project dependency rules.
• Written ADRs or equivalent decision processes clear for engineers and agents.
• Excellent written communication, partnering with leadership on roadmaps.

Responsibilities

• Owns the module boundary model — isolation, contracts, composition roots and CI tests.
• Drives the ADR process and audits drift between decisions and implementation, including agent code.
• Authors playbooks for agents to use, reviews outputs against specs, and signs off changes.
• Grows the shared platform library (eventing, mediation, auditing, observability) based on real module needs.
• Defines non-deterministic output verification via an eval harness in CI.
• Governs domain pack extensibility and semantic definitions the AI Analyst reasons over.
• Gatekeeps new module/pack proposals regarding cost, reuse and fit before start.
• Scouts new technologies and methodologies for potential adoption at OEC.
• Mentors engineers on platform conventions and agent-ready specs.

Skills

7+ years software

.NET/C#

ASP.NET Core

EF Core

ADR writing

Technical writing

Roadmap alignment

Tools

Claude Code

Python service

TypeScript

Single-spa

LLM tooling

Job description

OEC Analytics is the analytics platform for OEC's product suite: a governed semantic layer over OEC's data, a query execution path that serves it, and an embeddable widget runtime that product teams render inside their own applications - multi-tenant, with governance in the core rather than bolted on per consumer. Its flagship surface is a conversational AI Analyst: users ask questions of their data in natural language and build dashboards by describing them. Product lines plug in through a declarative domain pack contract, not bespoke integrations.

The platform is early. Module boundaries, the pack model, and the AI Analyst's production build are being defined now, not maintained — on top of a formal decision record and machine-enforced architecture tests that already exist.

Key Responsibilities & Duties (essential to the job)

• Owns the module boundary model — isolation, contracts-only dependencies, composition roots — as specs precise enough for agents to implement, and architecture tests that enforce them in CI.
• Drives the ADR process, and audits for drift between documented decisions and real implementation, including agent-generated code.
• Authors the playbooks coding agents work from, reviews their output against spec, and decides which changes — schema, cross-module contracts, security — need human sign-off.
• Grows the shared platform library (eventing, mediation, auditing, observability), driven by real module needs rather than ported wholesale.
• Defines how non-deterministic output is verified — an eval harness in CI that gates prompt and model changes.
• Defines and governs the domain pack extensibility model, including the semantic definitions the AI Analyst reasons over.
• Gatekeeps new module and pack proposals, assessing integration cost, reuse, and capability-inventory fit before implementation begins
• Scouts and justifies new technologies and methodologies, including AI and agentic tooling, for adoption at OEC.
• Escalation point for cross-team design issues; mentors engineers on platform conventions and on writing agent-ready specs.

Experience, Skills and Key Competencies

Required

• 7+ years building software, including hands-on architecture of modular or service-oriented backends where you introduced and enforced the boundaries — not just designed them.
• Strong .NET/C#, ASP.NET Core, and EF Core, with comfort enforcing dependency-direction rules across a multi-project solution.
• Written ADRs or an equivalent lightweight decision process, clear enough for engineers and agents to act on without shared tacit context. Excellent written communication is core to this role.
• Partnering with tech leadership and product management on roadmap alignment.

Preferred

• Directed AI coding agents (Claude Code) on real production codebases — multi-file, multi-step implementation work, not chat-based suggestions.
• Architected LLM-backed product features: structured tool calling, keeping the model outside the trust boundary, and measuring non-deterministic output rather than hand-reviewing it.
• Verification that scales without a human in the loop: architecture tests and linters for what you can assert, eval harnesses for what you can only measure.
• Security architecture for systems that execute model-proposed actions — sandboxed execution, allowlist validation of generated queries, pre-query tenant credential scoping.
• Polyglot comfort: the AI Analyst is a Python service alongside the .NET backend.
• Analytics/BI platforms, semantic modeling (dbt/MetricFlow-style), and TypeScript micro-frontends (currently single-spa) — useful, and we will support ramp-up here.

Must also be able to demonstrate the following skills and abilities

• Holds a line on architectural boundaries under delivery pressure, while staying pragmatic about incremental adoption.
• Proves architectural patterns out — with specs, tests, and agents — before mandating them.
• Collaborates well across platform engineering and the downstream product teams integrating with Analytics.
• Judges trade-offs between delivery speed and long-term coherence, including how much autonomy to grant an agent and how accurate a model-generated answer must be before a customer sees it.