Javascript developer Jobs in Markham, ON

As an hourly paid, fully remote JavaScript Engineer for AI Data Training, you will review complex AI-generated code and explanations or generate new ones, evaluate the reasoning quality and step-by-step problem-solving, and provide expert feedback that helps models produce answers that are accurate, logical, and clearly explained. You will assess solutions for accuracy, clarity, and adherence to the prompt, identify errors in methodology or conceptual understanding, fact-check information, write high-quality explanations and model solutions that demonstrate correct methods, and rate and compare multiple AI responses based on correctness and reasoning quality.

This role is with SME Careers, a fast-growing AI Data Services company and subsidiary of SuperAnnotate that provides AI training data for many of the world’s largest AI companies and foundation model labs. Your work will directly help improve the world’s premier AI models while giving you the flexibility of impactful, detail-oriented remote contract work.

Key Responsibilities :

• Develop AI Training Content : Create detailed prompts in various topics and responses to guide AI learning, ensuring the models reflect a comprehensive understanding of diverse subjects.
• Optimize AI Performance : Evaluate and rank AI responses to enhance the model's accuracy, fluency, and contextual relevance.
• Ensure Model Integrity : Test AI models for potential inaccuracies or biases, validating their reliability across use cases.

Your Profile :

• Minimum 2+ years of professional JavaScript experience in production environments.
• Strong understanding of closures, async / await, prototype-based inheritance, and JavaScript event loop behavior, with deep proficiency in modern Vanilla JavaScript (ES6 / ES2015+).
• Proven ability to evaluate correctness, readability, and performance of JavaScript code, including identifying subtle logic and edge-case issues.
• Hands-on work experience in software engineering, preferably in roles involving code review, mentoring, or technical design discussions.
• Significant experience using LLMs or AI coding assistants while programming, combined with a critical mindset for validating their output.
• Excellent English writing skills, capable of producing clear, concise, and pedagogical technical explanations.
• Strong proficiency with at least one major frontend framework (such as React, Angular, or Vue.js) or backend runtime (such as Node.js with Express or NestJS).
• Minimum Bachelor’s degree in Computer Science or a closely related technical field.
• Previous experience with AI data training, data annotation, or evaluation of AI-generated technical content is a strong plus; Minimum C1 English proficiency and a highly detail-oriented working style are required.
• Preferred : contributions or merged PRs in JavaScript or TypeScript open-source projects, familiarity with bundlers and tooling (Webpack, Vite, Rollup), frontend–backend integration and Node.js runtime behavior, reviewing typed API layers, DTOs, or schema-driven designs, and experience evaluating frontend logic, async patterns, and state management.