Senior Full Stack Engineer

Salary range: B2B - 35 E/h + VAT 💰

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

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:

• Full-stack & Versatility: Broad technical perspective with an emphasis on adaptability across modern software stacks and architectures, favoring breadth and quick ramp-up over narrow specialization

• Frontend & TypeScript: Strong production experience with modern React and TypeScript (including Node.js, async patterns, testing, and monorepo tooling).

• Backend & Scripting: Working proficiency with Python for backend services, evaluations, analysis, and automation tooling

• AWS Beyond Serverless: Practical hands-on experience across the AWS ecosystem—extending beyond serverless (Lambda, Step Functions, DynamoDB, Bedrock) to broader architectural components such as containers (ECS/EKS), networking, compute, and IAM

• LLM features in production: Has shipped features leveraging LLM APIs (prompts, tool calling, structured output, long context) and can describe the eval that gated release, what failed, and what changed

• AI Champion Mindset: Enthusiastic, proactive embrace of AI-assisted engineering tools in daily workflows (e.g., Copilot, Cursor, LLM APIs) combined with the drive to champion AI-first practices and productivity across the team

• Infrastructure as Code: Able to read and safely modify Terraform configurations across environments

• Data: Hands-on experience with both NoSQL and SQL stores, including schema changes and live-system migrations

• Observability: Able to design metrics, logs, and alarms for non-deterministic systems, and effectively debug production issues from them

• CI/CD: Proficiency with modern CI/CD pipelines, ideally GitLab CI/CD

• Communication: Fluent written and spoken English, with the ability to articulate trade- offs clearly and align team members around technical decisions

Desirable:

• Multi-agent systems, MCP servers, or evaluation frameworks

• LLM cost control: model routing, prompt caching, token budgets

• Prompt-injection defense and agent security

• GraphQL for internal APIs and tooling

• Code intelligence or retrieval work (indexing, symbol search, knowledge bundles)

• Kubernetes, AWS AppSync, and EventBridge

• Playwright/Cucumber test automation

• Claude Certified Developer or Claude Certified Architect (Anthropic)

What’s in it for you?

• Strong community: Work alongside top professionals in a friendly, open-door environment

• Growth focus: Take on large-scale projects with a global impact and expand your expertise

• Tailored learning: Boost your skills with internal events (meetups, conferences, workshops), Udemy access, language courses, and company-paid certifications

• Endless opportunities: Explore diverse domains through internal mobility, finding the best fit to gain hands-on experience with cutting-edge technologies

• Flexibility: Enjoy flexibility – full remote working possibilities

• Care: We've got you covered with company-paid premium medical package through Luxmed

• Benefits: Access the MyBenefit cafeteria platform, allowing you to choose perks that best suit your lifestyle and needs

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.

With delivery centers in Wrocław and Gdańsk, our 300+ professionals in Poland drive forward-thinking solutions for global clients. Join a community where collaboration sparks innovation—and your impact reaches millions.

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.