HumanitApp
  • Home
  • Roles
  • Talent networks
  • Weekly
  • Role Match
  • Tools
  • Saved
Submit CVGet weekly role alerts
← Back to all roles

Verified partner opportunity

Senior Software Engineer, Backend (Node.js, TypeScript, Rust)

$50 - $80 / hour

MercorUnited States - RemoteFull-time

Join a high-scale consumer platform team as a Senior Backend Engineer, building the services behind digital experiences used by millions of people every day.

Is this a fit?

  • You can show recent, specific work involving AI evaluation, Clinical reasoning, Rust.
  • The listed commitment of 40 hours/week fits your schedule.
  • You can communicate your reasoning clearly in the application language.

Apply on Mercor

Complete your application with Mercor. No HumanitApp account or fee.

What happens next

  1. Continue to the official listing and enter your application details; have your resume ready.
  2. Complete the role-specific screen or assessment requested by the partner.
  3. Confirm availability, location eligibility and work authorization if requested. The partner determines the exact process.

Last verified 2026-09-26

Exact listing verified. HumanitApp is independent from Mercor and may receive a referral fee; the partner controls assessment and hiring.

Read our Mercor review
Ready to continue?Senior Software Engineer, Backend (Node.js, TypeScript, Rust)

Official role description

Join a high-scale consumer platform team as a Senior Backend Engineer, building the services behind digital experiences used by millions of people every day.

1. Overview

We're partnering with a large enterprise technology organization to place a Senior Software Engineer on a platform team that powers its core customer-facing experiences across web and mobile. The team works across Engineering, UX, Product, Business, and Analytics to ship fast, iterate through continuous experimentation and customer feedback, and integrate advanced capabilities such as Generative AI into production services. We're seeking senior backend engineers with hands-on Node.js, TypeScript, and Rust experience and a deep understanding of how the web works at scale. This is a full-time commitment of 40 hours per week.

This is a W-2 employment position with Cincinnatus LLC, with the opportunity to be placed within a leading enterprise client's engineering organization as part of their extended workforce.

2. Key Responsibilities • Lead delivery of scoped features through collaborative engineering teams, keeping work aligned with platform and system objectives. • Design, develop, test, and maintain high-quality, efficient services in Node.js, TypeScript, and Rust, across the full software lifecycle and CI/CD. • Build and optimize server-to-server integrations and API layers (REST and GraphQL) that serve high-traffic, customer-facing applications. • Integrate AI/ML capabilities into product services and use generative AI tools to improve engineering productivity. • Contribute to solution design, conduct code reviews, and apply best practices for scalable, secure, and maintainable systems. • Monitor application performance, support defect resolution, and drive continuous improvement. • Mentor peers and contribute to knowledge sharing and engineering excellence across the team.

3. Core Qualifications • 4+ years of professional software engineering experience (or a Bachelor's degree in Computer Science or a related field and 3+ years), building production systems at a recognized, high-scale organization. • Hands-on production coding experience in Node.js and TypeScript on the backend. • Hands-on coding experience in Rust, in production services, performance-critical modules, or substantial systems work. • Strong web fundamentals: HTTP semantics, cookies, headers, caching, sessions, and server-to-server communication patterns (auth between services, timeouts, retries). • Experience building or operating high-traffic, consumer-facing web platforms. • Experience with GraphQL on Node.js (schema design, resolvers, federation) is a plus. • Familiarity with web accessibility standards is a plus. • Demonstrable career progression to senior-level ownership. • Ability to engage reliably for at least 40 hours/week during weekdays. • Excellent written and verbal communication skills, and the ability to explain complex technical concepts clearly to broad audiences.

About Cincinnatus LLC: Cincinnatus LLC is an enterprise staffing company that partners with leading technology companies to source and employ highly skilled professionals for contingent and contract-based opportunities. Cincinnatus serves as the employer of record for these engagements, providing W-2 employment, payroll, benefits, and compliance, while placing employees directly within client teams to work on high-impact initiatives.

Equal Employment Opportunity: Cincinnatus is proud to be an Equal Employment Opportunity employer. We do not discriminate based upon race, religion, color, national origin, sex (including pregnancy, childbirth, reproductive health decisions, or related medical conditions), sexual orientation, gender identity, gender expression, age, status as a protected veteran, status as an individual with a disability, genetic information, political views or activity, or any other legally protected characteristic.

Relevant skills

AI evaluationClinical reasoningRustSoftware engineering

Who this role may fit

This opportunity may suit professionals with relevant experience in AI evaluation, Clinical reasoning, Rust, Software engineering. Review the official description and requirements before applying.

Compensation context

The listing states $50 - $80 / hour. Confirm the final rate, workload, and payment terms during the official application process.

Qualification checklist

  • You can show recent, specific work involving AI evaluation, Clinical reasoning, Rust.
  • The listed commitment of 40 hours/week fits your schedule.
  • You can communicate your reasoning clearly in the application language.
  • You are comfortable with project availability and hours varying over time.

Not the right fit?

Use your CV to find relevant roles on HumanitApp. This is separate from a partner application.

Match my CV →

New roles, once a week.

Optional role alerts from HumanitApp. Subscribe only if you want weekly emails.

Get weekly role alerts →

Before you apply

Referral and application questions

Can I start immediately through an Instant Work Offer?

This listing is not a promise of immediate work. Mercor may send separate offers to prequalified candidates. Read how Instant Work Offers work.

How should I compare the listed pay?

The listing states $50 - $80 / hour. Confirm the final rate, workload, and payment terms during the official application process.

Does Apply use a referral link?

Yes. The button opens the exact verified Mercorlisting using the referral URL published for this role.

Is HumanitApp the employer?

No. HumanitApp independently curates the opportunity. The partner platform manages applications and hiring decisions.

Must I share my details here?

No. Choose the primary Apply action to continue directly without giving HumanitApp your name or email address.

Continue exploring

Related verified roles

View category
Code

Cybersecurity Research Expert – Offensive Security & Vulnerability Research

$200 - $250 / hour

Code

Senior Software Engineer, Full Stack (Python, Java, Rust, C#, C++)

$90 - $110 / hour

Code

Engineering & Software Domain Expert

$65 - $105 / hour

Code

Applied Engineer, Evaluations Role

$100 - $120 / hour