Sr. Full-Stack Software Engineer

Weekday AI; United States; Remote; USD 69,000 - 138,000; Part time

Job summary

Weekday AI is seeking an experienced Senior Full-Stack Software Engineer for a remote, contractor role. You will work across frontend and backend stacks, translating and refining implementations, debugging complex issues, and validating solutions in production systems.

The ideal candidate has hands-on expertise across multiple languages, strong architectural understanding, and the ability to navigate unfamiliar codebases with independence and focus.

Qualifications

• Significant professional experience building production-grade full-stack applications.
• Hands-on experience on both frontend and backend development.
• Proficiency with multiple programming languages and tech stacks.
• Strong understanding of APIs, databases, and system integrations.
• Ability to navigate unfamiliar codebases and deliver high-quality results.

Responsibilities

• Full-Stack Development: build, enhance, and debug front-end and back-end components across production applications.
• Feature Implementation: create user-facing features, services, APIs, and data models.
• End-to-End Troubleshooting: trace requests and data flows across all layers.
• Codebase Analysis: understand architecture and identify dependencies and patterns.
• Complex Debugging: diagnose issues across state, contracts, persistence, and deployment.
• Cross-Language Development: translate and improve implementations across languages.
• Code Review and Validation: assess code for correctness, efficiency, security, and maintainability.

Skills

Full-stack mindset

Debugging

Problem solving

Independent work

Tools

Python

React

JavaScript

Java

Node.js

Rust

Golang

TypeScript

Job description

This role is for one of our clients

Pay: 50–100/hour

Location: Global, fully remote

Job Type: Contractor (~15 hours per week)

Schedule: Flexible — you choose the hours and days you work, including weekends if desired, as long as there is activity.

Required Skills: Python, React, JavaScript, Java, Node.js, Rust, Golang, TypeScript

We are looking for highly skilled Full-Stack Software Engineers to contribute to an AI training project involving software development, technical problem-solving, debugging, system architecture, and code evaluation.

We are seeking an experienced Senior Full-Stack Software Engineer with strong hands‑on expertise across both front‑end and back‑end development. The role involves creating, solving, reviewing, and validating complex software‑engineering tasks across the application stack, as well as translating complete software implementations from one programming language to another.

The ideal candidate should have substantial experience building and maintaining production‑grade applications, working across multiple programming languages, and understanding end‑to‑end system architecture. You should be comfortable navigating unfamiliar codebases, debugging complex issues, evaluating technical solutions, and ensuring code quality, performance, security, and maintainability.

Key Responsibilities

1. Full‑Stack Development: Develop, enhance, and debug front‑end and back‑end components across production applications.
2. Feature Implementation: Build user‑facing features and the supporting services, APIs, database structures, and data models.
3. End‑to‑End Troubleshooting: Trace requests and data flows across browsers, front‑end applications, APIs, back‑end services, databases, and third‑party integrations.
4. Codebase Analysis: Navigate unfamiliar repositories, understand existing application architecture, and identify dependencies and implementation patterns.
5. Complex Debugging: Diagnose and resolve issues involving application state, API contracts, authentication, data persistence, network communication, and deployment.
6. Cross‑Language Development: Evaluate, modify, translate, and improve software implementations across multiple programming languages while preserving functionality and correctness.
7. Code Review and Validation: Assess AI‑generated and developer‑written code for correctness, completeness, efficiency, security, scalability, and maintainability.
8. Technical Problem‑Solving: Design reliable solutions to challenging engineering problems and validate implementations against defined requirements and specifications.

Required Qualifications

• Significant professional experience developing and maintaining production‑grade full‑stack applications.
• Strong hands‑on expertise in both front‑end and back‑end software engineering.
• Professional experience working with multiple programming languages and adapting to different technology stacks.
• Solid understanding of browser‑based applications, APIs, application state management, databases, and service integrations.
• Experience designing, understanding, and contributing to the architecture of complete software systems.
• Ability to navigate unfamiliar codebases and quickly understand existing implementations.
• Strong debugging, analytical thinking, and problem‑solving capabilities.
• Experience reviewing code and evaluating solutions for performance, reliability, security, and maintainability.
• Ability to work independently, manage complex technical tasks, and deliver high‑quality results.

Selection Process

1. Participate in an AI interview lasting approximately 30 minutes.
2. Complete a technical assessment, if required.
3. Proceed through the hiring manager review.

Compensation Structure

Compensation is output‑based, with payment provided for each task that meets the specified project requirements and quality standards. Task complexity and completion time may vary depending on the nature of the work, the engineer’s experience, and their workflow.

Minimum submission requirements apply, and selected engineers must complete and submit a specified minimum number of tasks each week.

Start Timeline and Availability

The hiring process typically moves quickly, with roles often filled within 48 hours. Candidates should be available to begin immediately. Upon selection and completion of onboarding, engineers are expected to start their first tasks within 24–48 hours.