Frontend Developer

Ryan Mahoney

Why this role is hard · Ryan Mahoney

At this level, the hard part is finding engineers who can own a feature without needing constant handholding. We see plenty of candidates who can build a component in isolation but struggle when requirements are vague or the API breaks. They need to show they can debug complex state issues while communicating clearly with designers and backend teams. Writing clean markup is not enough because they must advocate for the outcome and ensure the work ships without creating debt. Finding someone with both technical depth and independent decision-making skills is rare in the current market.

Core Evaluation

Critical questions for this role

The competency and attitude questions below are where the hiring decision is made. They run in the live interview rounds and are calibrated to the level selected above.

21 Competency Questions

1 of 21

  1. Discipline

    Core Frontend Engineering

  2. Job requirement

    Accessibility & Standards

    Conducts accessibility audits and fixes compliance issues (t44).

  3. Expected at Mid

    Mid-level developers independently conduct accessibility audits and remediate compliance issues within their scope to ensure inclusive product delivery. This prevents accessibility gaps that exclude users, create legal risks, and require costly retrofits that delay releases.

Interview round: Hiring Manager Technical Deep Dive

Recall a situation where you implemented interface requirements for diverse users.

Positive indicators

  • Mentions WCAG
  • Tests with tools
  • Considers motor/vision

Negative indicators

  • Mouse only
  • Ignores screen readers
  • No standards mentioned

16 Attitude Questions

1 of 16

Accountability Mindset

The consistent willingness to take ownership of tasks, decisions, and outcomes, including errors, ensuring deliverables meet quality standards and commitments are honored without external enforcement.

Interview round: Hiring Manager Technical Deep Dive

How do you handle a scenario where you realize you won't meet a committed deadline?

Positive indicators

  • Alerts team ASAP
  • Proposes plan B
  • Updates stakeholders

Negative indicators

  • Waits until deadline
  • Makes excuses
  • Hides delay

Supporting Evaluation

How candidates earn the selection conversation

The goal is to reduce effort for everyone by collecting more useful signal before adding more interviews. Lightweight application prompts and structured screens help the panel focus live time on the candidates most likely to succeed.

Stage 1 · Application

Filter at the door

Runs the moment a candidate hits Submit. Disqualifying answers end the application; everything else is captured for review.

Knock-out Questions

1 of 2

Application Screen: Knock-out

Do you have at least 2 years of professional experience developing and shipping production web applications using React and TypeScript?

Yes
Qualifies
No
Auto-decline

Video-Response Questions

1 of 2

Application Screen: Video Response

Describe how you communicate technical limitations to a backend team pushing for accelerated API delivery. What specific steps do you take to align expectations and propose viable alternatives?

Candidate experience

REC
0:42 / 2:00
1Record
2Review
3Submit

Response time

2 min

Format

Recorded video

Stage 2 · Resume Screening

Read the resume against fixed criteria

Reviewers score every application that clears the door against the same criteria. Stronger reviews advance to live interviews; weaker ones are archived without further screening.

Resume Review Criteria

8 criteria
Independently architects and delivers complete features, managing complex client-side state and data flow.
Develops, documents, and maintains reusable UI libraries ensuring consistency across applications.
Profiles application performance and implements strategies to optimize load times and runtime efficiency.
Implements monitoring tools and deployment safeguards to detect errors and manage release risk.

Does the cover letter or personal statement convey clear relevance and familiarity with the job?

Does the resume indicate required academic credentials, relevant certifications, or necessary training?

Is the resume complete, well-organized, and free from formatting, spelling, and grammar mistakes?

Does the resume show relevant prior work experience?

Stage 3 · During Interviews

Where the hire is decided

Interview rounds use the competency and attitude questions outlined above, then add tests, work simulations, and presentations that reveal deeper evidence about how the candidate thinks and works.

Coding Test

1 of 2

Live Interview · Coding Test

Without AI

Design a component that handles large datasets. Implement server-side sorting and pagination. Manage loading/error states and expose a clean prop interface.

Build a generic DataTable component that accepts a data-fetching function. Implement server-side sorting, pagination controls, and debounced search. Ensure type-safe props, handle loading and empty states gracefully, and avoid unnecessary re-renders.

With AI

Use AI to generate initial state management and fetching logic, then critically refactor for type safety and render efficiency. Explain trade-offs.

Build a generic DataTable component that accepts a data-fetching function. Implement server-side sorting, pagination controls, and debounced search. Ensure type-safe props, handle loading and empty states gracefully, and avoid unnecessary re-renders.

Response time

20 min

Positive indicators

  • Clean separation of UI and data logic
  • Proper TypeScript generics and type inference
  • Debounced inputs and controlled loading states
  • Efficient rendering and memoization strategies
  • Refining AI-generated state into stable, predictable flows
  • Adding strict TypeScript constraints to loose AI types
  • Identifying and fixing unnecessary re-renders
  • Clear rationale for architectural choices

Negative indicators

  • Fetching on every render without stabilization
  • Tight coupling between table UI and specific data shapes
  • Missing pagination or sorting state synchronization
  • Inefficient re-renders due to unoptimized state updates
  • Accepting AI code without performance profiling
  • Ignoring generic type constraints or unsafe casts
  • Failing to implement debouncing or race condition guards
  • Inability to explain state synchronization logic

Presentation Prompt

Walk us through your approach to co-designing an API contract and integrating a complex data flow for a past feature. Discuss how you ensured type safety, handled error and loading states, and aligned with backend and product teams.

Format

deck-and-walkthrough · 20 min · ~2 hr prep

Audience

Engineering hiring panel (2-3 engineers, 1 product/design partner)

What to prepare

  • 3-5 slides covering the problem context, contract design approach, implementation challenges, and outcomes.
  • Use anonymized, public, or school/side project work if necessary.

Deliverables

  • A concise slide deck
  • A structured verbal walkthrough focusing on reasoning, collaboration, and technical decisions

Ground rules

  • Use only work you are permitted to share; redact proprietary data as needed.
  • Focus on process, decision-making, and cross-team alignment rather than proprietary code.

Scoring anchors

Exceeds
Demonstrates strategic API shaping, anticipates failure modes comprehensively, shows strong cross-team influence, and articulates a clear type-safety and contract evolution strategy.
Meets
Presents a coherent integration story, covers basic contract alignment and error states, and demonstrates competent collaboration and type-safety practices.
Below
Lacks depth in API design, ignores error handling or validation, shows minimal collaboration awareness, or fails to justify technical choices.

Response time

20 min

Positive indicators

  • Clearly articulates frontend data needs and proactively shapes backend contracts
  • Demonstrates robust error, loading, and fallback state handling
  • Explains type-safety tooling choices (e.g., OpenAPI, GraphQL, TypeScript) and contract evolution
  • Reflects on cross-team negotiation and how alignment was achieved

Negative indicators

  • Treats the API as a black box without discussing contract design or negotiation
  • Lacks a coherent strategy for error handling or data validation
  • Struggles to explain how cross-team alignment or type safety was achieved
  • Focuses exclusively on UI implementation while ignoring data layer considerations

Work Simulation Scenario

Scenario. You are tasked with building a reusable AsyncResourcePicker component that allows users to search, select, and link external project dependencies. The backend team is designing the GraphQL API, and you need to co-design the contract and client-side integration strategy.

Problem to solve. Drive a discussion to define the API contract, client-side caching, error handling, and type-safe integration patterns that will serve multiple product areas.

Format

discovery-interview · 35 min · ~1 hr prep

Success criteria

  • Defines clear, type-safe API contract boundaries
  • Addresses caching, pagination, and error recovery strategies
  • Considers performance and bundle size implications
  • Aligns on contract testing and mock data strategy

What to review beforehand

  • GraphQL fundamentals, React Query/SWR patterns, and our current API client setup

Ground rules

  • Lead the conversation to uncover backend constraints and frontend needs. Focus on contract design and integration architecture.

Roles in scenario

Backend Engineer (informed_partner, played by cross_functional)

Motivation. Wants a stable, efficient API that minimizes over-fetching and supports frontend caching without requiring backend changes.

Constraints

  • Database queries are expensive; must limit full-text search frequency
  • API will be consumed by web and mobile teams
  • Strict latency budget of 200ms for search queries

Tensions to introduce

  • Backend prefers cursor pagination but frontend design implies offset-based
  • Search results include nested objects that could bloat payloads
  • Mobile team needs different field sets than web

In-character guidance

  • Answer questions honestly about database constraints and API capabilities
  • Provide realistic latency and payload size estimates
  • Clarify versioning and deprecation policies when asked

Do not

  • Do not volunteer backend implementation details unless asked
  • Do not design the frontend component for the candidate
  • Do not compromise on latency or payload constraints without trade-off discussion

Scoring anchors

Exceeds
Elicits precise backend constraints, architects a type-safe, resilient integration with clear caching and error boundaries, and establishes contract testing practices.
Meets
Defines a solid API contract, addresses core integration patterns (caching, errors, types), and aligns on deployment independence with minor gaps.
Below
Relies on guesswork, ignores performance or error handling constraints, or proposes brittle, tightly coupled integration patterns.

Response time

35 min

Positive indicators

  • Asks targeted questions about data shape, latency, and error semantics
  • Proposes type-safe client generation and contract testing strategies
  • Designs caching, pagination, and fallback patterns aligned with constraints
  • Negotiates API boundaries that balance frontend UX and backend performance

Negative indicators

  • Assumes API behavior without verifying constraints or latency budgets
  • Overlooks error handling, loading states, or type safety
  • Proposes tight coupling that blocks independent frontend/backend deployment
  • Fails to consider caching strategy or payload efficiency

Progression Framework

This table shows how competencies evolve across experience levels. Each cell shows competency at that level.

Core Frontend Engineering

5 competencies

CompetencyJuniorMidSeniorPrincipal
Accessibility & Standards

Implements basic ARIA attributes and semantic HTML following accessibility guidelines and team conventions.

Conducts accessibility audits and fixes compliance issues (t44).

Integrates accessibility into the design system and workflow, ensuring compliance is baked into development processes rather than retrofitted.

Advocates for inclusive design standards across product lines, establishing org-wide accessibility compliance that meets WCAG guidelines and legal requirements.

Component Architecture & State

Builds basic components with local state following team patterns and established conventions.

Implements complex state management and component composition (t03, t18, t22).

Architects scalable component libraries and state synchronization patterns that support team-level development and cross-project reuse.

Sets strategy for state management across multiple products, architecting scalable component libraries and synchronization patterns that serve the entire organization.

Markup & DOM Manipulation

Implements static UI components from designs using standard HTML/CSS patterns with semantic structure and basic responsiveness.

Develops responsive layouts and handles dynamic DOM updates efficiently (t28, t35).

Optimizes DOM structures for performance and accessibility compliance, focusing on architectural decisions rather than basic implementation.

Defines organizational standards for markup semantics and DOM architecture that enable consistent, accessible, and performant UI implementation across all products.

Performance Optimization

Identifies basic performance issues using standard metrics and profiling tools with guidance.

Implements optimizations like code splitting and lazy loading (t16, t17, t30).

Conducts deep profiling and resolves complex rendering bottlenecks to ensure performance budgets are consistently met across critical user journeys.

Defines performance budgets and optimization strategies for the platform, establishing org-wide Core Web Vitals targets and enforcement mechanisms.

Testing & Quality Assurance

Writes unit tests for basic functions and components following team testing standards and coverage requirements.

Develops integration tests and maintains test coverage standards (t09, t25).

Implements end-to-end testing strategies and CI quality gates that ensure reliability across the team's deliverables.

Defines quality metrics and testing architecture for the organization, establishing CI quality gates and testing standards that eliminate entire classes of frontend incidents.

Platform & Product Operations

5 competencies

CompetencyJuniorMidSeniorPrincipal
Build & Release Engineering

Executes build commands and deploys to staging environments following established CI/CD workflows and team procedures.

Configures build tools and manages dependency updates (t37, t53).

Optimizes CI/CD pipelines and manages release trains, reducing organizational complexity through tooling and process improvements.

Architects the deployment infrastructure and release strategy for the organization, establishing progressive delivery patterns and release governance that enable safe, rapid deployments across teams.

Data Integration & APIs

Fetches data using standard HTTP methods and handles loading states, errors, and basic response processing.

Implements caching strategies and error handling for API calls (t23, t24).

Designs data synchronization patterns and optimizes network usage, co-defining API contracts with backend partners to ensure efficient data flows.

Defines API contracts and data governance standards across the organization, establishing type-safe client patterns and data synchronization strategies that enable efficient front-back collaboration.

Observability & Analytics

Implements basic logging and tracks predefined events using existing instrumentation patterns and analytics platforms.

Configures dashboards and alerts for frontend errors (t54, t55).

Designs tracing strategies and analyzes user behavior data to enable effective incident response and data-driven decision making.

Defines observability standards and data-driven decision frameworks for the organization, establishing unified monitoring, tracing, and analytics that enable proactive incident prevention and informed product decisions.

Security & Privacy

Follows security guidelines for input validation and authentication flows as defined by team standards.

Implements secure data handling and mitigates common vulnerabilities (t27, t34).

Conducts security reviews and integrates security into SDLC, ensuring vulnerabilities are identified before reaching production.

Defines security architecture and compliance strategy for the organization, establishing frontend security postures and data privacy frameworks that protect user data at scale.

Technical Leadership & Strategy

Participates in planning sessions and estimates assigned tasks accurately with guidance from senior team members.

Leads small features and mentors junior developers (t41, t42).

Drives technical decisions and cross-team collaboration, translating business needs into technical plans while influencing without direct authority.

Sets technical vision and aligns engineering strategy with business outcomes, delivering multi-quarter technical roadmaps and representing engineering externally to drive organizational impact.