AceUp - Full Stack Engineer (Ruby/React)

Department: Engineering

Location: Argentina

Compensation: $66K – $102K • Offers Equity • Offers Bonus

Employment Type: FullTime

About the company

The Opportunity:
AceUp is evolving from a traditional SaaS platform into an AI-first leadership development engine. We are looking for a Full Stack Engineer who excels at bridging established core systems with cutting-edge AI services. You will be the primary developer responsible for bringing our new AI capabilities "to the glass." While our ML team builds the intelligence in Python, you will build the experience. You will architect the React frontends that users interact with and the Ruby backend logic that orchestrates data between our core platform and our new AI microservices.

The Tech Stack:

• Core Backend: Ruby on Rails (Monolith & Services).

• Frontend: React.js (Modern hooks, Context API).

• AI Integration: Interfacing with Python-based AI Microservices (FastAPI/GCP Cloud Functions).

• Database: PostgreSQL, Firestore.

• Infrastructure: GCP (Google Cloud Platform), AWS What You Will Do

• Build Interactive AI Interfaces: Develop rich, responsive React UIs for our new conversational features. You will handle complex frontend states, including streaming text responses (like ChatGPT), real-time updates, and interactive data visualizations.

• Orchestrate AI Integrations: Write the Ruby code that acts as the "glue" between our core application and the external Python AI services. You will ensure secure, efficient data hand-offs and handle asynchronous job processing.

• Architect for Latency: AI models can be slow; your UI shouldn't be. You will implement optimistic UI updates, loading states, and WebSocket/ActionCable connections to keep the experience buttery smooth.

• Maintain & Scale the Core: While shipping new features, you will continue to maintain and improve the health of our existing Ruby on Rails codebase, ensuring it scales as we add heavy AI workloads.

• Collaborate Cross-Functionally: Work closely with the ML Engineers to define the API contracts (JSON schemas) needed for your frontend features.

Who you Are

• A "Product-First" Engineer: You care deeply about the user interaction. You know that a great AI model is useless if the UI is clunky or the loading spinner spins forever.

• Polyglot-Curious: Your strength is Ruby/React, but you aren't afraid to read a Python file to understand how the API you are consuming actually works.

• State Management Expert: You understand that "Chat" is a difficult UI problem. You know how to manage history, optimistic updates, and streaming data on the frontend.

• System Integrator: You are comfortable working in a service-oriented architecture where the frontend, core backend, and AI service must all stay in sync. Requirements

• Experience: 4+ years of professional full-stack development experience.

• Frontend Strength: Deep experience with React.js. You can build complex components without relying on heavy third-party libraries for everything.

• Backend Strength: Strong proficiency in Ruby on Rails. You understand ActiveRecord performance, background jobs, and API design.

• Integration Experience: Proven experience consuming REST or gRPC APIs and handling asynchronous workflows.

• Language: Conversational English is required. Nice to Haves

• Familiarity with Python. (You won't code it daily, but reading it helps).

• Experience with WebSockets or real-time data streaming.

• Experience with GCP services (Cloud Run, Pub/Sub).

Interview process:

• Silver Screening interview

• First meeting with client: Intro Intro Call + Problem Solving

• Take Home Challenge

• Technical Interview

• Interview w/Product