Prompt Engineer

At MNTN, we put our people first, full stop. This allows our company culture to be defined by our team members and their shared values, like trust, ambition, quality, radical honesty, and compassionate leadership. It’s why we all really love working for the Hardest Working Software in Television™ (and also why we were named one of Ad Age’s Best Places To Work in 2025.)

We pride ourselves on bringing unrivaled performance and simplicity to Connected TV advertising. Our self-serve technology makes running TV ads as easy as search and social, helping brands drive measurable conversions, revenue, site visits, and more. It’s what led MNTN to being named one of Fast Company's Most Innovative Companies in 2023. You can learn more about us and everything we do by visiting https://mountain.com/.

We’re committed to innovation that empowers, not replaces. At MNTN, AI is a tool for growth, enhancing efficiency while keeping a people-first approach. Our goal is to streamline workflows and drive new solutions—without compromising the human element that makes our company great.

So if wanting to do more, own more, and make a bigger impact comes naturally to you, then you may be the person we're looking for to join us in our next stage of growth.

We’re looking for a Prompt Engineer to join MNTN’s engineering team and help define how AI powers our video generation platform. You’ll be hands-on with the prompts and AI workflows that turn structured inputs—brand details, product info, story beats, timing, and creative constraints—into production-ready video outputs. This role is critical to making sure our AI systems are reliable, scalable, and built for real-world use. By owning prompts end to end, setting quality standards, and continuously testing and monitoring performance in production, you’ll have a direct impact on product quality and the trust our customers place in MNTN’s platform.

What you’ll do

• Design, write, and iterate on prompts for story and script generation, scene and structural descriptions, and dialog, narration, and timing instructions

• Build and maintain AI workflows that coordinate LLMs and generative media models while enforcing schemas, rules, and timing constraints

• Handle failures, edge cases, and retries across AI-driven systems

• Actively test AI outputs to identify failure modes, regressions, and inconsistencies

• Define evaluation criteria and lightweight metrics to assess output quality

• Monitor production outputs and continuously improve prompts and workflows

• Partner with product and engineering teams to translate requirements into durable AI systems

• Document prompt patterns, evaluation methods, and workflow behavior

What you’ll bring

• Strong experience with prompt design for large language and generative AI models

• Experience testing, validating, and monitoring AI outputs in real systems

• Comfort working with structured inputs (schemas, constraints, validation rules)

• Systems-oriented mindset with attention to reliability and repeatability

• Ability to iterate quickly based on real-world output feedback

• Familiarity with multi-model or agent-style AI systems

Nice to have

• A strong eye for storytelling, pacing, and visual composition

• Experience working with video, media, or creative tooling

• Experience with Node.js and Typescript

MNTN Perks

• 100% remote within the US

• Flexible vacation policy

• Annual vacation allowance for travel related expenses

• Three-day weekend every month of the year

• Competitive compensation

• 100% healthcare coverage

• 401k plan

• Flexible Spending Account (FSA) for dependent, medical, and dental care

• Access to coaching, therapy, and professional development

About MNTN

Our recruiters will always reach out using an email address ending with @mountain.com OR @mntn.com. If you’re contacted by someone without that address and they mention a Reference Code (which we never use), then that ain’t us folks. Tell those trolls to take a hike–you’re waiting to climb a MNTN.

MNTN provides advertising software for brands to reach their audience across Connected TV, web, and mobile. MNTN Performance TV has redefined what it means to advertise on television, transforming Connected TV into a direct-response, performance marketing channel. Our web retargeting has been leveraged by thousands of top brands for over a decade, driving billions of dollars in revenue.

Our solutions give advertisers total transparency and complete control over their campaigns all with the fastest go-live in the industry. As a result, thousands of top brands have partnered with MNTN, including Tarte, Decked, and National University.

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