Software Developer III

GraceMark Solutions; Jacksonville (FL); On-site; USD 140,000 - 200,000; Full time

Job summary

GraceMark Solutions in Jacksonville, FL is seeking a senior hands-on backend engineer to own the technical integrity of a core platform. You will make build-vs-configuration decisions under architectural direction and lead a small specialist team, delivering secure, high-quality code on time.

The role centers on event-driven, CQRS-style design with strong domain modeling, multi-tenant security, and AI-assisted development workflows.

Qualifications

• 8–12 years hands-on, currently building and delivering work.
• Event-driven architecture with event sourcing / CQRS in design practice.
• Strong domain-modeling judgment to identify new patterns.
• Multi-tenant security with server-side isolation and encryption.
• Delivery leadership: accountable, communicates clearly to stakeholders.
• AI-assisted development with verification of AI-generated code/tests.
• Test strategy defines suite coverage including edge cases.
• Proficient in Python and relational-database projections.
• Serverless-first cloud-native approach; container fluency.
• Direct, fast-moving teamwork with strong decision discipline.

Responsibilities

• Own technical integrity of a core backend platform and deliver within scope.
• Make build-vs-configuration calls under architectural direction.
• Lead a small specialist team; ensure secure, on-time delivery.
• Apply AI-assisted development tools with rigorous verification.
• Define and enforce test strategies and CI gates.

Skills

Hands-on engineering

Event-driven architecture

CQRS

Domain modeling

Multi-tenant security

Delivery leadership

AI-assisted development

Test strategy

Python

Relational databases

Serverless

Containerization

Tools

CI/CD tooling

Container tooling

Serverless frameworks

Job description

Senior hands-on engineer to own the technical integrity of a core backend platform — holding engineering quality, making build-vs-configuration calls under architectural direction, and anchoring a small specialist team. Accountable for delivery of their scope: built right, secured, on time, and clearly communicated. A hands-on expert engagement: building, not advising or overseeing.

This is core software development and transaction-processing work — building the operational backbone of a live system. It is not an analytics, data-warehousing, or business-intelligence role.

Must-have summary — the hard bar

A candidate must clear all of these to be a fit:

• 8–12 years hands-on, currently building — recent, personally-built and delivered work they can speak to in depth.
• Event-driven architecture designed and built — event sourcing / CQRS as a design practice, not just message-bus usage.
• Domain-modeling judgement — can tell a genuinely new pattern from a variation of an existing one.
• Multi-tenant / multi-party security — has enforced tenant isolation server-side; understands event integrity and encryption at rest and in transit.
• Delivery leadership — accountability, execution discipline, clear communication (including to non-technical stakeholders), and sound escalation judgment.
• AI-assisted-development fluency and verification — directs and verifies AI-generated code and test suites, catching plausible-but-wrong output rather than rubber-stamping green.
• Test-strategy judgment — defines what a suite must prove and spots the gaps automated generation leaves.
• Strong Python; working relational-database / projection proficiency.
• Serverless-first cloud-native — object storage and serverless compute as primary building blocks; container fluency; local cloud emulation.
• Executes within locked decisions without relitigating; thrives in a direct, fast-moving small team.
• 8–12 years hands-on, with recent work you personally built and delivered.
• Deep event-driven architecture — event sourcing, CQRS, or similar patterns designed and built, not just used.
• Strong domain-modeling judgment — telling a genuinely new pattern from a variation of an existing one.
• Strong specification skill — turning intent into instructions precise enough to build right the first time.
• Secure-by-design across the platform's layers:

• Domain / data isolation — multi-tenant / multi-party isolation enforced server-side and re-authorized per request; paths and UI are never the isolation boundary.
• Event / transport integrity — event authenticity and tamper-evidence (message signing), and encryption in transit across all edges and internal calls.
• Encryption at rest — across the relational store, the event log, and object / lakehouse storage, with customer-managed keys.

• Security verification of AI-generated code — catches injection vectors, leaked secrets, and authorization bypasses in generated output before they land.
• Test strategy and verification judgment — defines what a suite must prove, and reviews generated tests for genuine coverage rather than green-but-hollow passing (edge cases, error paths, and boundaries automated generation tends to skip).
• Owns the test bar and CI gate — defines what must pass before merge, given humans gate generated changes.
• Hands-on with automated testing frameworks — unit / integration testing, service mocking / stubbing, and test-data generation, alongside local cloud emulation.
• Ownership and delivery discipline — accountable for getting work to done, holds a quality bar under time pressure, drives outcomes rather than waiting for direction.
• Clear communicator — surfaces risk early, reports status crisply, explains technical trade-offs to non-technical stakeholders.
• Sound escalation judgment — knows what to own and decide versus what to surface upward.
• Executes within locked architectural decisions without relitigating them; works well in a direct, fast-moving small team.
• Fluent with modern AI-assisted development tooling — directs and verifies AI-generated code with rigor.
• Working proficiency with relational databases and read-model / projection design — enough to hold the data layer if needed.
• Serverless-first cloud-native build — object storage and serverless compute as primary building blocks.
• Container fluency — containerized local development and container-image packaging of compute.
• Local cloud emulation for development and testing.
• Effective working from principles and open problems, not pre-written tickets.

Advantageous

• Configuration-driven platform experience — change absorbed as config, not rebuilds.
• Federated / keyless CI credentials, secrets management, least-privilege access design.
• Container orchestration — good to know, not required.
• Domain exposure in a data-intensive, operationally complex industry.

Assessment

A deep-dive on something you personally built, secured, and delivered — including how you enforced tenant isolation and protected data in transit and at rest — plus how you'd specify a non-trivial feature, verify the result, and judge whether its test suite actually proves correctness.