Crest Advisory Group is seeking a Full-Stack Developer who is not just a strong coder, but deeply fluent in AI-assisted development and building for massive scale. You will be building on a large-scale veterinary care platform powered by Marcia - our proprietary AI ecosystem - that is being rolled out to 20,000+ clinics in 100+ countries across 6 portals (Consumer, Clinic, Enterprise, Platform, Referral, Internal Admin), serving millions of consumers with tens of millions of concurrent sessions. This is not a traditional development role.
Our engineering culture is AI-first: Claude Code is your primary development tool, Cursor is your secondary. You must be comfortable working with agentic coding workflows, orchestrating sub-agents, and leveraging AI to ship faster, smarter, and with higher quality. You must also know how to write code that performs at scale - optimizing database queries, managing connection pools, building efficient caching layers, and designing systems that handle millions of concurrent users without degradation. Every PR goes through 5 automated review bots before human review. SonarCloud quality gates must pass on first push. Security hygiene is non-negotiable
Key Responsibilities
- Develop, optimize, and maintain Next.js-based front-end applications with pixel-perfect UI and high performance across all 6 portals
- Build and maintain NestJS-based APIs, microservices, and scalable back-end architecture with Prisma ORM
- Own Prisma migration workflows - schema changes, migration generation, seeding, and coordination with QA on data integrity
- Deploy and manage infrastructure on AWS and Google Cloud Platform (dual-cloud architecture)
- Implement and maintain multi-tenant architectures with tenant isolation at the code level - each portal has distinct user roles and data access patterns
- Use Claude Code as your primary AI-assisted coding tool to accelerate development, generate code, debug, and refactor
- Leverage Cursor as a secondary AI IDE for rapid iteration and code exploration
- Orchestrate and configure sub-agents within Claude Code for complex multi-step development tasks (test generation, documentation, migration scripts, code reviews)
- Build MCP (Model Context Protocol) integrations to connect AI tooling with platform data sources and workflows
- Write code that passes SonarCloud quality gates on first push - understand code smell resolution, quality gate criteria, and static analysis compliance (4,484+ issues being burned down in waves)
- Respond to and address feedback from 5 PR review bots (Devin, Bugbot, Codex, Copilot, Augment) in addition to human reviewers
- Work on front-end aspects including data extraction tools, dynamic scheduling, dynamic pricing, and workflow automation interfaces
- Optimize application performance for millions of concurrent users - efficient database queries, connection pooling, caching strategies (Redis/ElastiCache), lazy loading, and code splitting
- Design and implement scalable data access patterns - pagination, cursor-based queries, read replicas, and query optimization for high-throughput workloads
- Build systems that handle tens of millions of sessions without degradation - connection management, rate limiting, graceful degradation, and horizontal scaling patterns
- Profile and resolve performance bottlenecks across the full stack: frontend rendering, API response times, database query plans, and cache hit ratios
- Collaborate closely with designers, product managers, and QA to deliver features rapidly
- Contribute to the Marcia Enabled ecosystem - building AI-powered features across the platform
Responsibilities
Support customers via tickets, live chat, and outbound phone
Must-Have Skills
- AI-Assisted Development (Critical): Proven, daily experience using Claude Code (or equivalent agentic coding tool) as your primary development environment. You must demonstrate fluency in prompt engineering for code, sub-agent orchestration, multi-file refactoring via AI, and AI-driven test generation.
- Claude Code & Sub-Agents: Hands-on experience configuring and using sub-agents for parallelized tasks - writing tests, generating docs, running migrations, and reviewing PRs via AI.
- Cursor / AI IDE: Comfortable using Cursor as a secondary tool for code exploration, inline completions, and rapid prototyping
- Strong JavaScript/TypeScript and Next.js expertise (App Router, Server Components, Suspense)
- Deep proficiency with NestJS for backend API development, microservices patterns, and Prisma ORM (schema design, migrations, seeding)
- Scale & Performance (Critical): Proven experience building and optimizing applications serving millions of users with high concurrency. You must understand database query optimization, connection pooling, caching strategies, horizontal scaling patterns, and how to profile and resolve bottlenecks across the full stack
- Cost Optimization: Experience identifying and reducing unnecessary cloud spend, optimizing database costs, right-sizing infrastructure, and writing efficient code that minimizes compute and memory consumption at scale
- Proficiency with AWS services (ECS, Lambda, S3, CloudFront, RDS, SQS) and Google Cloud Platform (GKE, Cloud Run, BigQuery, Cloud Functions)
- Experience in multi-tenant front-end and back-end architecture with tenant isolation
- Redis/ElastiCache for caching and session management (this is core infrastructure, not optional)
- pnpm monorepo experience - the codebase is a monorepo with pnpm workspaces. This is a daily workflow requirement
- SonarCloud compliance - understanding quality gates, code smell categories, and writing clean code that passes static analysis
- Proficiency with CI/CD pipelines (GitLab CI, GitHub Actions) and deployment automation
- Comfortable with remote development environments - developers work on EC2 dev boxes accessed via Tailscale VPN, not local machines. SSH-based workflows required
- Experience with real-time features: Socket.io, Redis, BullMQ
- Security hygiene: IP allowlists, secret scanning, and push protection are enforced at the GitHub org level. Pushing secrets triggers alerts. Security consciousness is non-negotiable
Nice-to-Have Skills
- Experience building or integrating MCP servers and tools
- Background in LLM integration (API calls, prompt management, token optimization)
- Exposure to serverless architecture and microservices integration on AWS/GCP
- Experience in healthcare/veterinary/scheduling-heavy applications
- Knowledge of performance optimization for high-scale consumer-facing apps
- Experience with CockroachDB or distributed SQL databases
- Familiarity with AI automation frameworks (LangChain, CrewAI, or custom agent pipelines)
- Familiarity with Supabase or similar database integrations
Work Environment & Culture
- Global, diverse team with members from India, Pakistan, Ukraine, Prague, London, Brazil, and the US
- AI-first development culture - Claude Code and Cursor are standard tooling, not optional extras
- Every PR reviewed by 5 automated bots before human review - 0 unresolved threads required for merge
- Remote dev boxes on EC2 accessed via Tailscale VPN - not local development
- Expect frequent tool and tech stack shifts to keep up with AI innovation
- Flexible but structured work shifts to overlap with global teams
- Performance-based incentives (weekly, monthly, and quarterly competitions with bonuses)
- Hubstaff time tracking is mandatory - screenshots and activity logs are reviewed daily. This is not optional
Engagement Details
- Initial evaluation period: 1-2 weeks part-time or test project, leading to full-time role
- Commitment: Minimum 6 months (extendable based on performance and project needs)
- Exit clause: 14 days’ notice
- NDA and IP assignment agreement required prior to accessing any Crest systems, code, or data
- Technical assessment (HackerRank or equivalent) is part of the screening process
- Trial evaluation criteria: During the 1-2 week trial, you will be assessed on: quality and accuracy of deliverables, communication responsiveness, ability to work within Crest’s tooling and workflows, time management and Hubstaff compliance, and cultural fit with the team’s AI-first, fast-paced operating style
- AI Culture: AI tools are integrated into every function at Crest, not just engineering. You’ll be expected to adopt AI-assisted workflows, evaluate AI outputs critically, and continuously improve how you leverage these tools in your role
Job Type: Full-time
Pay: R$8,889.00 - R$17,312.00 per month
Work Location: Remote
