Role Description

Cultured Supply is hiring a junior software engineer to work closely with our lead engineer, designing and implementing feedback loops and revision mechanisms for our platform, Mission Control, and its AI‑powered workflows.

This is a generalist software engineering role with an emphasis on product quality, manual and automated testing, and AI evaluation. You’ll test complete product workflows, investigate unexpected behavior, create reproducible test cases, and help build the systems we use to evaluate quality over time.

Your work will span exploratory product testing, data-quality checks, evaluations for LLM-powered features, etc. You’ll help us determine not only whether the software technically works, but whether its outputs are accurate, useful, consistent, and aligned with the intended user experience.

Although the role emphasizes QA and evaluation, it isn’t limited to manual testing. You’ll write code, build internal testing and evaluation tools, contribute to product features, and work across the Mission Control stack, including the frontend, APIs, databases, integrations, and AI-powered systems.

This position is intended for someone who is approaching university graduation or graduated within the past two years. We’re looking for an early-career engineer who has built meaningful projects, enjoys understanding how software and AI systems behave, and wants to grow quickly inside a small, ambitious team.

We don’t expect you to arrive with experience in every testing or evaluation framework. We do expect curiosity, attention to detail, strong technical fundamentals, and the persistence to investigate problems thoroughly.

Employment: Full-time

Location: In person at our office in San Jerónimo, Monterrey. Being located in Monterrey, Mexico, is required.

Language: Spanish and highly proficient or fluent English.

If you’re still completing your degree, you must be available to join us during working hours.

Responsibilities

- Test Mission Control’s product workflows from end to end.
- Perform exploratory and manual testing to identify failures, confusing behavior, and edge cases.
- Build and maintain automated tests for critical application flows.
- Design and maintain evaluations for LLM-powered features and AI-generated outputs.
- Define test cases, evaluation criteria, expected behavior,



and quality standards.
- Build internal tools that make testing, evaluation, debugging, and quality monitoring more effective.
- Improve test data, observability, logging, and development workflows.
- Contribute to product features and quality improvements across the Mission Control stack.
- Work closely with engineering and operations to turn real business processes into reliable software.
- Use AI development tools productively while understanding, reviewing, and verifying their output.
- Participate in code review, technical planning, and the continuous improvement of our engineering practices.

What We Look For

- High agency: You can take an unclear problem, investigate it methodically, and move it toward a resolution.
- A strong learning instinct and genuine curiosity about how systems work and how they fail.
- Attention to detail without losing sight of the broader product and user experience.
- A habit of questioning assumptions and testing behavior beyond the happy path.
- The patience and persistence to investigate inconsistent or difficult-to-reproduce problems.
- The ability to explain issues clearly and distinguish symptoms from underlying causes.
- Comfort operating in a startup environment where priorities evolve and systems are still taking shape.
- Comfort using AI development tools.

Core Skills & Experience

- Currently approaching university graduation or graduated within the past two years.
- Strong software engineering fundamentals, including APIs, relational databases, and application architecture.
- Ability to investigate behavior across multiple parts of a system and communicate your findings clearly.
- Comfort working across the stack and learning unfamiliar tools when a project requires it.
- Familiarity with Git, pull requests, code review, and collaborative repositories.
- Ability to turn ambiguous product behavior into clear test cases and expected outcomes.




- Clear written communication and the ability to document defects, findings, and technical decisions.
- Evidence of your ability to build through internships, freelance work, university projects, or substantial independent projects.

You don’t need to check every box. If most of this resonates with you, we encourage you to apply.

You should be comfortable using tools such as Codex, Claude Code, Cursor, or similar coding agents. We don’t expect you to know every tool already, but we do expect curiosity, critical thinking, and a willingness to learn.

Nice to Have

- Experience with browser-testing tools such as Playwright or Cypress.
- Experience evaluating LLM outputs or other nondeterministic AI features.
- Familiarity with evaluation datasets, scoring criteria, prompt testing, or human-in-the-loop evaluation.
- Experience testing APIs, integrations, data pipelines, or CRM workflows.
- Familiarity with observability, logging, error tracking, or performance monitoring.
- An interest in usability, accessibility, visual QA, or product design.
- Experience shipping and maintaining a project used by real people.

About Cultured Supply

Cultured Supply builds modular, AI-native software that helps organizations take greater ownership of how they grow and operate.

We believe smaller businesses and owner-operators should have access to the same level of intelligence, infrastructure, and operational leverage as much larger organizations. Mission Control helps teams understand their markets, identify opportunities, manage customer relationships, and operate their go-to-market workflows more directly.

Our goal is to build tools that give people greater agency—helping them reach customers directly, make better decisions, and compete on their own terms.

Learn more at culturedsupply.com.

How to Apply

Email [email protected] or apply through this job posting with:

1. A short note explaining why you’re a good fit for the role.
2. Your CV.
3. Links to relevant work, such as GitHub repositories, deployed products, testing projects, evaluation systems, technical demos, or walkthrough videos.

Hiring Process

- If your application looks like a potential fit, we’ll schedule an initial interview.
- Selected candidates will complete a practical exercise followed by a second interview.

📌 Junior Software Engineer — Product QA & AI Evaluation (Monterrey)
🏢 Cultured Supply
📍 Monterrey