Ruby Rails Developer Jobs in Los Angeles, CA (NOW HIRING)

Jiffy.com is seeking a Sr. Software Development Engineer with deep hands-on experience orchestrating AI coding agents to ship production software at pace. Reporting directly to an Engineering Manager and working closely with Product, GM's and other cross functional teams, you will lead the charge on delivering end-to-end features across our e-commerce platform from storefront and checkout to internal tools and platform services while running multiple AI-driven work streams in parallel.
At Jiffy, engineers no longer write code by hand: every line that reaches production is produced, tested, reviewed, and deployed by coding agents (Claude Code, Codex, Cursor) under the direction of a human orchestrator. This role is perfect for an individual contributor who has already internalized the shift from “typing code” to “directing agents,” has strong architectural taste and review instincts, and wants to help define what an AI-native engineering org looks like. You will thrive here if you are a systems thinker, a builder by nature, and someone who gets more done by managing five parallel agents well than by writing a single function perfectly.
At this time, Jiffy is not able to sponsor or take over sponsorship of an employment visa (e.g., H-1B) for this position. Applicants must be legally authorized to work in the United States without employer sponsorship, now or in the future.

• Orchestrate AI coding agents (Claude Code, Codex, Cursor) across 3–6 concurrent work streams spanning features, refactors, bug fixes, and investigations using worktrees, sub-agents, and background tasks to maximize parallel throughput.
• Own features end-to-end: translate product intent into clear specifications, decompose work into agent-executable plans, drive agents through implementation, review every diff critically, run QA, land PRs, and verify production health.
• Design and architect scalable, reliable systems across our stack Rails 8 / Solidus e-commerce, GraphQL APIs, React 19 front end, Kubernetes infrastructure holding the architectural and judgment calls that agents cannot make.
• Raise the quality bar on AI-generated code by catching hallucinated APIs, enforcing secure and idiomatic patterns, and pushing back on output that is technically working but structurally wrong.
• Build and evolve Jiffy’s internal AI tooling: author skills, rules, prompts, MCP integrations, and evaluation harnesses that make the whole engineering org faster. Contribute to our shared .ai/ skills and rules library.
• Operate with production rigor: drive agents to produce meaningful test coverage (RSpec, Vitest, Playwright), monitor deploys, respond to incidents, and fully own the services you ship.
• Partner cross-functionally with Product, Design, Ops, and peer engineering teams to define and ship features; participate in architecture and code reviews; mentor engineers on AI-native workflows and orchestration patterns.
• Continuously identify where remaining manual work (QA, ops runbooks, data investigations, migrations) can be replaced by agents, and automate it.

Requirements

• Bachelor’s degree in Computer Science, Engineering, or a related field.
• 5+ years of professional software engineering experience shipping production systems at scale.
• Hands-on experience using AI coding agents (Claude Code, Codex, Cursor, or equivalent) as a primary development tool. This is mandatory. You must be able to walk through real features, refactors, or investigations delivered through agent orchestration — not occasional autocomplete usage.
• Proven ability to run multiple agents in parallel and manage concurrent work streams without losing quality, context, or accountability.
• Strong software design fundamentals: OO design, API design, data modeling, distributed-system reliability, and performance.
• Proficiency in at least one server-side language (Ruby, Python, Go, Java, or equivalent) and one modern front-end stack (React / TypeScript or equivalent), with the expectation that agents produce the code while you direct, review, and validate it.
• Experience with relational databases (Postgres / MySQL), SQL, and building or consuming REST or GraphQL APIs.
• Elite code-review skills: the ability to read, critique, and correct diffs at speed is the core competency of an AI-first engineer.
• Strong written communication — clear intent, clear PR descriptions, clear prompts. In an AI-first org, writing is the programming interface.
• A high level of integrity, accountability, and ownership, with a commitment to excellence across every deliverable.
• Desire to work in a fast-paced, ambiguous, high-autonomy environment.

• AI Tooling Builder: Experience authoring or extending AI developer tooling — custom skills, slash commands, MCP servers, sub-agents, evaluation harnesses, or prompt libraries used by a team.
• E-commerce Depth: Experience with Ruby on Rails and Solidus / Spree, or other large-scale e-commerce platforms.
• Modern Front End: Experience with React 19, TypeScript, GraphQL (Apollo), Tailwind, and modern state management (React Query, XState, Jotai).
• Cloud Native Operations: Experience operating services on Kubernetes (Istio, KEDA, Flagger) and modern observability stacks
• Automated QA at Scale: Experience driving agents to maintain and extend test suites with Playwright, Vitest, and RSpec.
• AI-Native Leadership: Track record of mentoring engineers on AI-native workflows, publishing internal patterns, or leading an organization through the shift away from manual coding.
• Measurable Throughput Gains: Documented improvements in features-per-week, cycle time, or review time directly attributable to AI adoption.
• High-Growth Environment: Experience shipping in a fast-paced, agile environment at a high-growth startup or tech company.

Benefits

What We Offer

The base compensation for this role is expected to range from $195,000 - $265,000 per year. Actual compensation will be based on a variety of factors, including skills, experience, qualifications, and overall fit for the role.
Total compensation may include base salary, performance-based bonuses, equity, and benefits. Final offers are tailored to each candidate and take into consideration their background and years of experience.

• Comprehensive Benefits: Full medical, dental, and vision coverage, with a portion of premiums paid by Jiffy.
• Retirement Planning: 401(k)
• Wellness Support: Annual wellness benefits to help you stay healthy and balanced.
• Tools for Success: Choice of MacBook or PC laptop, plus equipment for your home office setup.
• Perks & Extras: Annual credit of $200 to use on our website plus more team merch drops than you will know what to do with!
• Professional Development: Annual stipend to support your learning and career growth.

EEO

Jiffy is proud to be an equal opportunity employer. We do not discriminate in hiring or any employment decision based on race, color, religion, national origin, age, sex (including pregnancy, childbirth, or related medical conditions), marital status, ancestry, physical or mental disability, genetic information, veteran status, gender identity or expression, sexual orientation, or other applicable legally protected characteristics. Jiffy considers qualified applicants with criminal histories, consistent with applicable federal, state and local law.