Kamil Toporek - Senior Software Engineer & AI Developer

Q: Where is Kamil based?

Kamil is based in Oświęcim, Poland and prefers 100% remote projects.

Q: What languages does Kamil speak?

Kamil speaks the following languages: English (Advanced), Polish (Intermediate) .

Q: How many years of experience does Kamil have?

Kamil has at least 10 years of experience. During this time, Kamil has worked in at least 4 different roles and for 4 different companies . The average length of individual experience is 3 years and 6 months . Note that Kamil may not have shared all experience and actually has more experience.

Q: What is Kamil's latest experience?

Kamil's most recent position is Senior Software Engineer & AI Developer at Concentrix .

Q: What companies has Kamil worked for in recent years?

In recent years, Kamil has worked for Concentrix and Synox .

Q: Which industries is Kamil most experienced in?

Kamil is most experienced in industries like Information Technology (IT) .

Q: Which business areas is Kamil most experienced in?

Kamil is most experienced in business areas like Information Technology (IT) , Product Development , and Business Intelligence .

Q: Which industries has Kamil worked in recently?

Kamil has recently worked in industries like Information Technology (IT) .

Q: Which business areas has Kamil worked in recently?

Kamil has recently worked in business areas like Information Technology (IT) and Product Development .

Recommended expert

Oświęcim, Poland

Experience

Oct 2023 - Present

2 years 5 months

Senior Software Engineer & AI Developer

Concentrix

Designed and delivered a backend core platform for API access, provisioning workflows, and internal service orchestration, closely resembling embedded connectivity and telecom-style platforms.
Owned the end-to-end backend architecture, evolving a Rails-heavy monolith toward a distributed, service-oriented system without disrupting live customers.
Built API-first Ruby on Rails services responsible for orchestration, validation, rate limiting, and backward-compatible contracts consumed by internal and external clients.
Extracted high-throughput, latency-sensitive services into Go, significantly improving scalability while keeping Rails as the coordination layer.
Introduced event-driven workflows using async workers, message queues, and retry-safe processing, eliminating fragile synchronous flows.
Designed and implemented idempotent APIs and state-driven workflows, preventing duplicate provisioning and inconsistent system states.
improved p95 latency by ~33% and sustained 99.95% availability in systems handling millions of monthly requests.
Added Redis caching and performed PostgreSQL query and index optimization, reducing database load and stabilizing peak traffic behavior.
Built a small but critical Elixir-based concurrent worker service to handle highly parallel background workloads, leveraging BEAM concurrency where it outperformed existing solutions.
Established observability-first design, implementing metrics, structured logs, and distributed tracing to support fast incident diagnosis.
Evolved the system safely using feature flags, staged rollouts, and production metrics as the source of truth, avoiding risky rewrites.
Built TypeScript-based internal dashboards and tooling tightly integrated with backend APIs to support operations, monitoring, and incident response.
Actively participated in incident response and on-call workflows, making real-time decisions under pressure while balancing business impact, speed, and reliability.

Aug 2020 - Sep 2023

3 years 2 months

Full Stack Engineer

Synox

Designed and built Go-based backend services exposing secure REST APIs for external partner integrations.
Modeled core transactional domain logic (partners, transactions, states) with strong consistency guarantees.
Implemented high-concurrency APIs using Go, ensuring correctness under load.
Designed clear API contracts, validation rules, and error models for predictable partner integrations.
Built TypeScript dashboards for internal teams and partners to monitor transactions and system state.
Solved duplicate and retry issues by designing idempotent APIs and strict state transitions.
Used Redis for fast lookups and short-lived state while keeping PostgreSQL as the source of truth.
Improved throughput and response times compared to legacy implementations.
Reduced partner integration issues through well-documented APIs and predictable behavior.
Enabled operations teams to detect and resolve issues faster via operational dashboards.
Delivered a scalable backend foundation ready to onboard new partners and higher traffic.

May 2018 - Mar 2020

1 year 11 months

Full Stack Developer

Look4IT

Built and maintained backend services using Python (Django, FastAPI) and Ruby-style REST patterns, delivering stable APIs for data-heavy platforms.
Designed API contracts, validation, and error models to keep integrations predictable and reduce partner/client friction.
Developed data processing and analytics workflows, exposing results through REST endpoints consumed by product dashboards.
Implemented real-time and near-real-time dashboards using streaming/WebSocket-style updates and API-driven operational views.
Improved data quality by ~25% by introducing anomaly detection and automated checks integrated into backend workflows.
Standardized CI/CD with Docker + GitLab CI, improving release reliability and reducing environment drift.
Worked in security- and compliance-sensitive environments, ensuring correct handling of sensitive data, auditability, and operational readiness.

Apr 2015 - Jan 2018

2 years 10 months

Junior Software Engineer

Kenja K.K.

Built event ingestion services processing millions of events/day using Python and Node.js.
Designed Kafka-based pipelines for analytics and personalization.
Optimized queries, indexing, and caching for high-traffic APIs.
Implemented segmentation and analytics APIs with efficient access patterns.
Collaborated closely with product teams on requirements and delivery.
Improved system stability through monitoring and performance tuning.
Documented backend services for long-term maintainability.

Industries Experience

See where this freelancer has spent most of their professional time. Longer bars indicate deeper hands-on experience, while shorter ones reflect targeted or project-based work.

Experienced in Information Technology (10 years).

Information Technology

Business Areas Experience

The graph below provides a cumulative view of the freelancer's experience across multiple business areas, calculated from completed and active engagements. It highlights the areas where the freelancer has most frequently contributed to planning, execution, and delivery of business outcomes.

Experienced in Information Technology (10 years), Product Development (7.5 years), and Business Intelligence (4.5 years).

Information Technology

Product Development

Business Intelligence

Summary

Senior Software Engineer, Backend with 10+ years of experience designing and building scalable backend platforms, APIs, and distributed systems across Ruby on Rails, Go, Python, and TypeScript. Proven track record delivering high-availability, API-first systems in telecom-like, fintech, and AI-driven domains, owning projects end-to-end from architecture to production. Strong focus on business impact, observability, reliability, and incremental system evolution from monoliths toward service-oriented architectures.

Designed and delivered backend core platforms similar to embedded connectivity systems, supporting provisioning, orchestration, and partner integrations.
Led incremental decomposition of Rails monoliths into Go-based services, improving scalability without downtime.
Achieved 99.95% availability in production systems handling millions of monthly requests.
Improved p95 API latency by ~33–40% through Go concurrency, Redis caching, and SQL optimization.
Built API-first architectures with clear contracts, versioning, validation, and idempotency.
Delivered high-throughput REST APIs consumed by external partners (fintech / SaaS / internal platforms).
Designed event-driven workflows using async workers, retries, and message-based orchestration.
Established observability-first systems with metrics, structured logs, and tracing.
Supported incident response and on-call workflows, resolving production issues under pressure.
Reduced manual operations by 30–40% through automation and backend tooling.
Built TypeScript dashboards and internal tools tightly coupled to backend APIs.
Worked comfortably across Ruby, Go, TypeScript, Python, and Elixir, learning fast where needed.
Delivered systems with strong business alignment, balancing speed, quality, and reliability.

Skills

Backend: Ruby On Rails, Go, Python (Fastapi, Django, Flask), Node.js, Elixir, Rest Apis, Api Versioning, Idempotency, Domain Modeling
Frontend: React, Next.js, Angular, Vue.js, Typescript/javascript (Es6+), Redux, React Query, Tailwind Css, Material Ui, Wcag, Performance Tuning
Ai & Ml: Llm Integration, Rag Pipelines, Embeddings & Vector Search, Semantic Search, Ai Chatbots, Function Calling, Automated Workflows, Safety Guardrails
Cloud & Devops: Aws, Azure, Gcp, Docker, Kubernetes, Ci/cd, Terraform, Github Actions, Gitlab Ci, Jenkins, Iac, Gitops
Databases: Postgresql, Mysql, Mongodb, Redis, Schema Design, Indexing, Query Optimization, Migrations, Analytics/event Data
Testing & Quality: Pytest, Jest, Cypress, Playwright, Integration & E2e Testing, Performance Testing, Ci-based Validations
Mobile (Android): Kotlin, Android Studio, Android Sdk

Languages

English

Advanced

Polish

Intermediate

Education

Kyoto University

Bachelor’s Degree · Computer Science · Kyoto, Japan

Certifications & licenses

AI Certificate

Calyptus

Profile

Created

January 2026

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Frequently asked questions

Do you have questions? Here you can find further information.

Where is Kamil based?

Kamil is based in Oświęcim, Poland and prefers 100% remote projects.

What languages does Kamil speak?

Kamil speaks the following languages: English (Advanced), Polish (Intermediate).

How many years of experience does Kamil have?

Kamil has at least 10 years of experience. During this time, Kamil has worked in at least 4 different roles and for 4 different companies. The average length of individual experience is 3 years and 6 months. Note that Kamil may not have shared all experience and actually has more experience.

What roles would Kamil be best suited for?

Based on recent experience, Kamil would be well-suited for roles such as: Senior Software Engineer & AI Developer, Full Stack Engineer, Full Stack Developer.

What is Kamil's latest experience?

Kamil's most recent position is Senior Software Engineer & AI Developer at Concentrix.

What companies has Kamil worked for in recent years?

In recent years, Kamil has worked for Concentrix and Synox.

Which industries is Kamil most experienced in?

Kamil is most experienced in industries like Information Technology (IT).

Which business areas is Kamil most experienced in?

Kamil is most experienced in business areas like Information Technology (IT), Product Development, and Business Intelligence.

Which industries has Kamil worked in recently?

Kamil has recently worked in industries like Information Technology (IT).

Which business areas has Kamil worked in recently?

Kamil has recently worked in business areas like Information Technology (IT) and Product Development.

What is Kamil's education?

Kamil holds a Bachelor in Computer Science from Kyoto University.

Does Kamil have any certificates?

Kamil has 1 certificate: AI Certificate.

What is the availability of Kamil?

Kamil is immediately available full-time for suitable projects.

What is the rate of Kamil?

Kamil's rate depends on the specific project requirements. Please use the Meet button on the profile to schedule a meeting and discuss the details.