Back to search
SIM Linkedin · Posted 1mo ago

Senior Software Engineer

San José, San José, Costa Rica

Linkedin
Continue to application Add your email once, then Caio opens the original posting.

Indexed description

We are looking for a Senior Back-End .NET Developer to play a key role in building and evolving high-performance, scalable backend systems.

You will work within a team contributing directly to the design and implementation of systems that are:

  • High-throughput and low-latency
  • Designed for scalability and resilience
  • Transitioning from legacy architectures to modern patterns

This is a hands-on engineering role where you will:

  • Write production-quality code daily
  • Contribute to architecture and technical decisions
  • Mentor other developers
  • Help adopt AI-assisted development practices effectively

How This Role Fits the Team

  • The Development Manager sets direction, architecture, and standards
  • You execute, influence, and elevate implementation quality
  • You act as a technical leader within the team, without formal people management responsibility

Key Responsibilities

Backend Development & System Design

Design, build, and maintain backend services using .NET / C#

Develop systems that support:

  • High concurrency and throughput
  • Low-latency APIs and processing

Contribute to system design decisions, including:

  • Service boundaries
  • Data models
  • API contracts

Modern Architecture & Migration

Contribute to the evolution from legacy systems to:

  • Microservices or modular monoliths
  • Event-driven architectures
  • Asynchronous processing models

Work pragmatically across:

  • Existing legacy codebases
  • New greenfield services

Performance & Reliability

Identify and resolve performance bottlenecks

Optimize:

  • Database queries (SQL Server)
  • API response times
  • Background processing pipelines

Ensure systems are:

  • Resilient under load
  • Observable and debuggable

Code Quality & Engineering Standards

Write clean, maintainable, and well-tested code

Contribute to and enforce:

  • Coding standards
  • Testing strategies (unit, integration)
  • Perform high-quality code reviews
  • Reduce technical debt in a pragmatic way

AI-Assisted Development

Use tools such as:

  • GitHub Copilot, Codex, Claude Code

Apply AI to:

  • Accelerate development
  • Improve code quality

Ensure outputs remain:

  • Correct
  • Secure
  • Maintainable

Collaboration & Agile Delivery

Work closely with:

  • Product Owners
  • QA engineers
  • Infrastructure / Platform teams

Contribute to:

  • Incremental delivery
  • Continuous integration and deployment
  • Support a Kanban / lean workflow with fast feedback loops

Mentorship & Technical Leadership

Support and mentor mid-level and junior developers

Share best practices across the team

Lead by example in:

  • Code quality
  • Problem-solving
  • Ownership

Required Experience

5+ years experience in backend development

Strong expertise in:

  • .NET / C#
  • SQL Server (or similar relational databases)

Experience building:

  • Scalable, distributed systems
  • High-performance APIs

Strong understanding of:

  • Asynchronous programming
  • Multithreading and concurrency
  • API design (REST, messaging patterns)

Technical Skills

.NET (Core / modern versions preferred)

SQL Server (indexing, query optimization, data modeling)

Experience with:

  • Message queues (e.g. RabbitMQ, Kafka)
  • Caching (e.g. Redis)

Familiarity with:

  • Microservices or modular architectures
  • Observability tools (logging, tracing, metrics)

Preferred Experience

Experience working in:

High-scale environments.

Exposure to:

  • Event-driven systems
  • Domain-driven design
  • Experience modernizing legacy systems
  • Familiarity with AI-assisted development tools

What We’re Looking For

  • Strong problem solver who takes ownership
  • Pragmatic engineer who balances speed and quality
  • Comfortable working in evolving architectures
  • Collaborative and team-oriented
  • Takes pride in building reliable, performant systems

What You’ll Get

  • Opportunity to work on high-scale, real-time systems
  • Exposure to modern architecture patterns and migration challenges
  • Ability to shape how AI is used in real engineering workflows
  • Work closely with senior leadership and influence technical direction
Free. 20 seconds. No password. See every match in this search.

Create a free Caio profile to unlock more results and save your role and location preferences.

Unlock free search
Want help applying to roles like this? Search Caio for free. If the repetitive CV tweaking gets heavy, Daniel can help set up Caio Agent.
Ask about Agent