Full stack developer Jobs in Newark, NJ

Purpose

We’re looking for a backend-leaning, Senior, Full Stack Engineer who will build AI-powered platforms, tools, and workflows that create value for our clients and empower our creative, strategy, operations, and account teams.

You’ll design and build backend services, data-centric components, and internal tools, with a strong focus on Python and modern cloud infrastructure. You will be hands-on with integrating large language models (LLMs) and other AI capabilities into real products, from early design through deployment, monitoring, and iteration.

Ideal Candidate

• You’re a strong backend-focused engineer who thinks in terms of systems, data models, and APIs.
• You’re comfortable hopping into simple frontend tasks when needed.
• Enjoys collaborating closely with cross-functional partners.
• You can translate requirements into scalable software that balances speed, quality, and reliability.
• You’re curious about AI and other emerging technology and excited to integrate them responsibly into real products.
• You take ownership of products, from design through deployment and maintenance.

Responsibilities

• Design, build and maintain backend services and APIs primarily in Python (FastAPI/Starlette), emphasizing clean design, performance, and reliability.
• Model data and write high‑quality SQL (primarily in BigQuery); use document databases (e.g., Firestore, MongoDB) where appropriate.
• Build, harden, and operate containerized services: author Dockerfiles (multi‑stage), manage image versions in Artifact Registry, and enforce container security/scanning.
• Deploy on GCP with Cloud Run and Compute Engine; leverage Secret Manager, Artifact Registry, Cloud Build/Deploy, and Cloud Monitoring/Logging; Kubernetes familiarity is a plus.
• Integrate LLM/AI capabilities with an agentic approach (tool/function calling, multi‑step orchestration/planning, retrieval/RAG, and memory) using providers such as OpenAI, Anthropic, and Google Gemini, as well as open‑weight models; implement evaluation, safety, and guardrails.
• Utilize our enterprise AI platform (Abacus.ai) that provides unified access to multiple language, image, and short‑form video models, plus prompt/version management, safety, and analytics; help define reusable patterns and abstractions for it across products.
• Collaborate with data partners on ELT pipelines; use BigQuery and Dataform for transformations and analytics use cases.
• Define and version API contracts (REST/GraphQL); document systems and interfaces.
• Apply security and privacy best practices (authn/z, IAM least‑privilege, secret handling, input validation, rate limiting).
• Establish observability (metrics, logs, traces) and conduct performance tuning; participate in pragmatic on‑call as needed.
• Write tests (unit/integration/e2e); maintain CI/CD pipelines; conduct code reviews; mentor junior engineers

Professional Skills

• Strong experience building backend services and APIs in Python (any modern web framework)
• Experience with document databases (e.g., Firestore, MongoDB).
• Containers & CI/CD: Docker/OCI image authoring, multi‑stage builds, image scanning/SBOMs, Artifact Registry; automated builds and deployments.
• Cloud: GCP first (Cloud Run and Compute Engine; Secret Manager, Artifact Registry, Cloud Build/Deploy, Monitoring/Logging); Kubernetes familiarity welcome; equivalent AWS/Azure experience acceptable.
• AI/LLM: Agentic architectures (tool/function use, multi‑step orchestration, retrieval/RAG, planners, memory), evaluation/guardrails/safety; experience with OpenAI, Anthropic, Google Gemini, and open‑weight models; familiarity with enterprise AI platforms that unify access to multiple model types.
• APIs & Services: REST/GraphQL, schema/versioning, authentication/authorization.
• Reliability: Testing (Pytest or similar), observability, performance tuning.
• Frontend: Able to handle simple UI needs using modern web technologies; framework agnostic.
• Process: Git‑based workflows and agile practices.

Competencies

• Communicates and collaborates effectively with creative, operations, strategy, and data partners.
• Outcome‑oriented problem solving; balances speed, quality, and security.
• Ownership and accountability; follows through and documents decisions.
• Growth mindset; receptive to feedback and continuous learning.
• Uses AI assistants responsibly with validation: evaluates outputs critically, adds tests, and adapts code to team conventions before submission.

Experience

• 4+ years of professional software engineering with a backend focus.
• Proven and demonstrable experience building Python (FastAPI/Starlette) services and APIs for cloud deployment (GCP preferred).
• Hands-on SQL experience in BigQuery; document database experience; Dataform exposure is a plus.
• Prior experience integrating LLMs in an agentic manner into production apps or adjacent ML systems.

Salary Range

Our estimated range for this role is $140k - $160k

Compensation packages are based on the skill level and experience each candidate brings to their role. There may also be a more senior or junior position available that could be a better fit with your expertise. Each level has its own compensation range.

We pride ourselves on competitive salaries, and ensuring pay equity exists across our organization. We benchmark each position against existing employee competencies and 4As compensation data which includes geographic and agency size benchmarks. We also meet with department leaders 3x/year to ensure we are supporting employees in living into their full potential. Our promotions are not limited to a specific time per year. Promotions are tied to performance.

Right To Work In The US

You must be authorized to work in the US for any employer. At this time, we are not sponsoring or providing assistance with obtaining work authorization.

McKinney is a place where everyone can grow. Studies have shown that marginalized communities such as women, LGBTQ+ and people of color are less likely to apply to jobs unless they meet every single qualification. However you identify, and whatever background you bring with you, please apply if this is a role that would make you excited to come into work every day.

We are in the office Tuesday/Wednesday/Thursday on a hybrid schedule. We look forward to meeting you!

About McKinney

McKinney is a creative agency that gets unfair attention for brands. In 2024, McKinney was named to Fast Company's Best Workplaces for Innovators list, as well as Ad Age's A-List and its list of Best Places to Work (2024 and 2025), reinforcing the agency's commitment to providing an exceptional workplace culture where employees thrive, and creativity flourishes. McKinney Health, the agency's Pharma and Wellness practice, launched in 2022, was named to MM+M Magazine's 2024 Agency 100 list. A Certified B Corporation, McKinney is part of the Cheil Worldwide network and has offices across the country, including Durham, New York, Los Angeles, Dallas, Phoenix, and Toronto. McKinney has been recognized by Cannes Lions, Effies, The One Show, D&AD, ANDY, CLIO, LIA, the Shortys, and The Webby Awards, among others. Client partners include brands such as Popeyes, Blue Diamond Growers, Little Caesars, Pampers, Henkel, Samsung, Indivior, Sherwin-Williams, Biogen and the Ad Council. For more information, visit mckinney.com.