Domain Architect

Stellar IT Solutions LLC; St. Louis (MO); Remote; USD 180,000 - 240,000; Full time

Benefits offered by this job

Remote work

Job summary

Stellar IT Solutions LLC is seeking a Domain Architect to own the domain's architecture, roadmaps, and key decisions. You will define domain boundaries, models, and shared vocabulary while setting which service owns each operation. Write ARB specs and ADRs, design idempotent workflows, API contracts, and concrete payment integrations.

Lead multi-team collaboration, mentor engineers, and drive durable workflows with Temporal and OpenTelemetry. Remote role in EST/CST with long-term contract.

Qualifications

• 10+ years of software engineering experience.
• 5+ years building payment systems.
• Expert in C# / .NET 8 and hands-on coding.
• Azure PaaS experience (App Service, Cosmos DB, Key Vault).
• Kafka in production experience.
• Domain-driven design with bounded contexts.
• Ability to define domain boundaries and service ownership.
• Experience with idempotent, exactly-once workflows.

Responsibilities

• Own the domain's architecture, tech roadmap, and key decisions.
• Define domain boundaries, domain model, and shared vocabulary.
• Decide which service or workflow owns each business operation.
• Write ARB-ready specs and ADRs.
• Design idempotent, exactly-once operations (sagas, outbox/inbox).
• Define API and event contracts with peer domains (OpenAPI, Protobuf).
• Establish trust boundaries: who computes data, who validates it, and consumers.
• Build durable workflows on Temporal and Nexus cross-domain calls.
• Architect payment workflows across the order lifecycle (auth, capture, refund).
• Lead PCI DSS scope reduction, tokenization, encryption, key rotation.
• Review production code and mentor senior engineers; lead migrations.

Skills

C# / .NET 8

Azure PaaS

Kafka in production

Domain-driven design

Leadership / mentoring

OpenAPI / Protobuf

API design

Durable workflow concepts

Tools

Temporal

Kubernetes

OpenTelemetry

Job description

Domain Architect

Remote - EST or CST timezone

Long Term Contract

Must Haves - -

• 10+ years of experience building payment systems
• Expert level C#/ .Net 8 - must be currently hands on
• Azure PaaS experience
• Kafka experience (in production)

Domain Ownership

• Own the domain's architecture, technical roadmap, and key decisions
• Define domain boundaries, domain model, and shared vocabulary
• Decide which service or workflow owns each business operation
• Write ARB-ready specs and ADRs

Architecture & Design

• Design idempotent, exactly-once operations (sagas, compensation, outbox/inbox, reconciliation)
• Define API and event contracts with peer domains (OpenAPI, JSON Schema, Protobuf)
• Establish trust boundaries: who computes data, who validates it, and what consumers can rely on

Workflows & Messaging

• Build durable workflows on Temporal, including Nexus cross-domain calls
• Set versioning standards for long-running workflows (patching, build IDs, replay testing)
• Design Kafka domain events with schema governance, retries, and dead-letter queues

Payments

• Architect payment workflows across the order lifecycle: create, edit, cancel, finalize, refund
• Design multi-tender orchestration across credit/debit, EBT SNAP, and EBT WIC
• Architect processor and benefit-provider integrations: auth, capture, void, refund, reversal
• Handle gateway timeouts and unknown outcomes without double-charging or leaving ghost charges
• Ensure EBT SNAP and WIC compliance with USDA FNS and state program rules
• Lead PCI DSS scope reduction, tokenization (network tokens, DPAN), encryption, and key rotation
• Extend the domain to new tenders such as Apple Pay, Google Pay, and split tender
• Support 3P marketplace payments: multi-capture, over-capture rules, and split settlement
• Partner with Finance on reconciliation, TLOG reporting, and general-ledger accuracy
• Define payment SLOs: auth rate, capture success, refund success, and compensation failures

Reliability & Quality

• Build resilience with Polly and Temporal retry policies
• Keep payment authorization well within checkout timeout budgets across Azure and GCP
• Instrument tracing across HTTP, Kafka, and Temporal with OpenTelemetry
• Set the testing strategy: unit, contract, replay, gateway simulation, and load

Leadership

• Review production code and mentor senior engineers
• Lead feature-flagged migrations off legacy paths
• Use AI coding agents and context engineering to speed up delivery

Must-Have

• [ ] 10+ years engineering, 5+ years building payment systems
• [ ] Domain-driven design: bounded contexts, domain events, context mapping
• [ ] Expert C# / .NET 8+ and still codes
• [ ] Temporal (preferred) or similar durable workflow engine in production
• [ ] Kafka in production
• [ ] Azure PaaS: App Service, Cosmos DB, APIM, Key Vault --> Similar technology on Google Cloud Platform
• [ ] Containerization, running code in Kubernetes
• [ ] Idempotency, saga, and reconciliation patterns in production
• [ ] PCI DSS and tokenization
• [ ] OpenTelemetry or APM observability design
• [ ] Track record of aligning multiple teams on a shared architecture

Nice-to-Have

• [ ] Temporal Nexus or Worker Versioning
• [ ] EBT SNAP / WIC processing
• [ ] Digital wallets: Apple Pay, Google Pay
• [ ] Gateway APIs: Aurus, Adyen, Fiserv, Worldpay, Chase
• [ ] Network tokens, DPAN, multi-capture, marketplace split settlement
• [ ] Multi-cloud: Azure + Google Cloud Platform
• [ ] LaunchDarkly-driven migrations
• [ ] .NET Aspire, Testcontainers, Mockoon/WireMock
• [ ] Retail finance feeds (TLOG, sales audit, GL)
• [ ] Grocery/omnichannel retail
• [ ] Google Cloud Platform experience