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Sr Full Stack Developer AI Native

Pennymac
2.9(735)
👥1k-5k
Software Engineering
Westlake Village, CA 91361
$90k - $150k
4 months ago
🤖 AI-First🛠️ Cursor-friendly💻 Open Source
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Explicitly mentions vibe coding and use of AI tools (Cursor, Copilot) for rapid prototyping and AI-assisted development while preserving architecture.

About the Role

Senior Full Stack Developer responsible for designing, developing, and maintaining responsive web applications using React, Node.JS, Ruby on Rails, and TypeScript while leveraging AI coding tools to accelerate development. The role focuses on building secure, high-quality user-facing products, rapid prototyping with AI, and mentoring junior developers.

Job Description

Role

Senior Full Stack Developer building and maintaining responsive, production-grade web applications. The role emphasizes both front-end and back-end engineering, rapid prototyping with AI coding tools, and delivering user-facing products that meet design and security standards.

Key Responsibilities

  • Design, develop, and maintain web applications using React, Ruby on Rails, Node.JS, HTML, CSS/SASS, JavaScript, Bootstrap, and SQL.
  • Leverage AI coding tools (Cursor, Copilot) to accelerate development while ensuring code quality and maintainability.
  • Build responsive, pixel-perfect pages from design mockups and ship user-facing products with measurable impact.
  • Rapidly prototype and iterate on solutions; participate in code reviews to ensure quality and security.
  • Troubleshoot complex technical issues with a focus on performance and security.
  • Collaborate with product and design teams to translate user needs into technical solutions.
  • Mentor junior developers and promote best practices in secure, user-focused development.

Requirements

  • 3+ years of full-stack software development experience in production environments.
  • 2+ years using TypeScript across front-end and back-end contexts.
  • Expert-level proficiency in React/ReactJS and modern front-end development patterns.
  • Strong backend foundation (Node.JS preferred) including scalable API design (REST or GraphQL), database schema design and optimization, authentication, and concurrency considerations.
  • Experience using AI coding tools (e.g., Copilot, Cursor) in professional workflows.
  • Experience with version control systems such as GitLab or GitHub.
  • Strong problem-solving, analytical, security-minded, and communication skills; ability to work independently in an agile team.

Preferred Qualifications

  • Experience with “vibe coding”—rapid prototyping using AI tools while maintaining architectural integrity.
  • Familiarity with Ruby on Rails, Jekyll, TypeScript, or Python.
  • Knowledge of web accessibility standards (WCAG).
  • Experience building LLM-powered features or AI agent systems.

Benefits

Comprehensive medical, dental, and vision; paid time off programs (vacation, holidays, illness, parental leave); wellness and employee recognition programs; onsite gyms and cafe-style dining at select locations; retirement benefits, life insurance, 401(k) match, tuition reimbursement; philanthropy programs including matching gifts and volunteer grants.

Compensation & Work Model

Salary range listed: $90,000 - $150,000. Work model: Office-based.

Tech Stack

ReactReactJSRuby on RailsNode.JSHTMLCSSSASSJavaScriptTypeScriptBootstrapSQLRESTGraphQLCopilotCursorGitLabGitHubJekyllPythonLLM

Skills

Front-end DevelopmentBack-end DevelopmentAPI DesignDatabase DesignResponsive Web DesignPerformance OptimizationSecurity Best PracticesTypeScriptCode ReviewsVersion ControlRapid PrototypingProduct-focused DevelopmentCollaborationMentoringProblem SolvingAgileAccessibility (WCAG)

Experience Level

Senior

Salary

USD 90,000 - 150,000/year

Benefits

  • Comprehensive Medical
  • Dental
  • Vision
  • Paid Time Off (vacation, holidays, illness, parental leave)
  • Wellness Programs
  • Employee Recognition Programs
  • Onsite gyms and cafe-style dining (select locations)
  • Retirement benefits
  • Life insurance
  • 401k match
  • Tuition reimbursement
  • Philanthropy Programs (matching gifts, volunteer grants, charitable grants, corporate sponsorships)
  • Office-based (Work Model: OFFICE)