Senior Full Stack Engineer

Ciklum is looking for a Senior Full Stack Engineer to join our team full-time in Brazil.

We are a custom product engineering company that supports both multinational organizations and scaling startups to solve their most complex business challenges. With a global team of over 4,000 highly skilled developers, consultants, analysts and product owners, we engineer technology that redefines industries and shapes the way people live.

About the role:

As a Senior Full Stack Engineer, become a part of a cross-functional development team engineering experiences of tomorrow. 

Responsibilities:

• Build production AI agents: develop TypeScript services on AWS (Lambda, Step Functions, DynamoDB, Bedrock) using Strands or LangGraph and AI SDKs
• Design agent behavior: define what the model investigates and what code enforces
• Sandbox agents: build read-only runtimes, scoped tool access, worktree-contained reads, and budget/timeout guards against model misbehavior
• Evaluate AI features: build golden sets and production replays, calibrate judges, gate changes on recall, precision and false-positive rate, and compare models and effort levels before release
• Ensure observability: emit reason-coded metrics and structured logs, alert on failures, and investigate production misses in Splunk and VictoriaMetrics
• Run infrastructure: maintain Terraform roots across environments under tagging and permission-boundary rules; improve GitLab CI/CD for build, test, deploy and quality gates
• Build integrations resilient to retries, rate limits, permanent failures and stale state
• Use AI to write/review code; keep agent context current
• Review AI-written changes for security, correctness and maintainability, catching issues tests miss
• Enable teams: configure assistants, skills, hooks and MCP servers; pair with engineers and share proven practices
• Build agent-facing tools: React and APIs for summaries, dashboards and internal tooling, with outputs readable by agents, CLIs and Slack
• Document systems with architecture/sequence diagrams, runbooks and decision records

Requirements:

• LLM production experience: shipped LLM API features (prompts, tool calling, structured output, long context); can explain release evals, failures and fixes
• TypeScript: strong production TypeScript and Node, async code, testing and monorepo tooling
• Python: proficiency in evals, analysis and scripting
• AWS serverless: Lambda, Step Functions, DynamoDB, IAM, event-driven design and Bedrock
• Infrastructure as code: safely read and modify Terraform across environments
• Data: hands-on NoSQL/SQL experience, including live schema changes and migrations
• Observability: design metrics, logs and alarms for non-deterministic systems and debug issues
• CI/CD: proficiency with CI/CD, ideally GitLab CI/CD
• AI-assisted development: daily AI coding assistant use; verify its output
• Communication: fluent spoken and written English; explain trade-offs and drive team adoption

Desirable:

• Multi-agent systems, MCP servers or eval frameworks (e.g. Strands Evals)
• LLM cost control: model routing, prompt caching, token budgets
• Prompt-injection defense and agent security
• React and GraphQL for internal tools
• Java and Spring Boot for existing service integration
• Code intelligence or retrieval (indexing, symbol search, knowledge bundles)
• Kubernetes, AWS AppSync and EventBridge
• Playwright/Cucumber test automation
• Claude Certified Developer or Architect (Anthropic)

What’s in it for you?

• Care: your mental and physical health is our priority. We ensure comprehensive company-paid medical insurance and mental health programs, 5 undocumented sick-leave days per year
• Tailored education path: boost your skills and knowledge with our regular internal events (meetups, conferences, workshops), Udemy license, language courses and company-paid certifications
• Growth environment: share your experience and level up your expertise with a community of skilled professionals, locally and globally
• Long-term employment with 20 working-days paid vacation and local bank holidays
• Flexibility: 100% remote work mode
• Opportunities: we value our specialists and always find the best options for them. Our Internal Mobility Program helps change a project if needed to help you grow, excel professionally and fulfill your potential
• Global impact: work on large-scale projects that redefine industries with international and fast-growing clients
• Welcoming environment: feel empowered with a friendly team, open-door policy, informal atmosphere within the company and regular team-building events

About us:

At Ciklum, we are always exploring innovations, empowering each other to achieve more, and engineering solutions that matter. With us, you’ll work with cutting-edge technologies, contribute to impactful projects, and be part of a One Team culture that values collaboration and progress.

As we expand into Latin America, every Ciklumer is helping to shape our story. Collaborate with seasoned experts and make a global impact backed by two decades of industry leadership.

Explore, empower, engineer with Ciklum!

Interested already? We would love to get to know you! Submit your application. We can’t wait to see you at Ciklum.

#LI-AD1