Release engineering
I own the release process end to end, balancing speed with stability and compliance. Database migrations and CI/CD are treated as part of the product, not an afterthought.
- Release management
- CI/CD
- DB migrations
Kostiantyn Denysov · Technical Lead at Deel, Berlin
I help engineering teams ship faster, and safer.
Release engineering, developer experience and backend architecture for a globally distributed engineering organization. Ten years of building the systems and teams behind reliable delivery.
Berlin · denysov.me · linkedin.com/in/denysovkos · github.com/denysovkos · Ukrainian, English, German, Russian
Track record
- Deployment
- AI-driven
- deployment pipeline replacing manual release sign-offs, with risk-scoring and automated error tracing
- Deel · now
- Leadership
- Team lead
- leading and coaching release managers and engineers for a globally distributed org
- Deel · now
- Incident practice
- Blameless
- incident review practice that turns lessons into lasting improvements
- Deel · now
- Release delivery
- 95%
- on-time delivery while leading cross-functional releases
- Join.com · 2024
- Database queries
- 1000×
- faster critical database queries
- Join.com · 2024
- Inter-service efficiency
- 50%
- more efficient inter-service communication through gRPC APIs
- Join.com · 2023
- Production bugs
- 60%
- fewer production bugs by building a testing culture
- Pixsy · 2022
- Architecture
- Bare metal
- led the move to microservices and bare metal for performance and cost
- Sonect · 2021
01What I do
The systems and habits that let teams release with confidence.
Developer experience
I set the vision and roadmap for developer platform and release tooling. Manual steps become automated, self-service workflows that engineers run themselves.
- Internal tooling
- Self-service
- Platform roadmap
Architecture and leadership
I lead the architecture of new platform services, with trade-offs and risks assessed up front. I coach engineers and build a code review culture that keeps quality high.
- System design
- Risk assessment
- Mentoring
02Now
Leading release management and developer experience at Deel.
Since Sep 2025
Deel
- An AI-driven deployment pipeline replacing the legacy release process: large, infrequent releases with manual sign-offs give way to frequent deploys with AI risk-scoring and automated error tracing.
- A team of release managers and engineers, led and coached to run delivery for a large, globally distributed engineering organization.
- One end-to-end release process that keeps speed, stability and compliance in balance.
- A developer platform and release tooling roadmap that replaces manual steps with automated, self-service workflows.
- Architecture of new platform services, led from first design.
- A blameless incident review practice that turns lessons into lasting improvements.
Partnering with engineering leadership and product teams to help everyone ship faster and safer.
03Experience
Ten years from fullstack engineer to leading a release engineering team.
-
Sep 2025 – present
Technical Lead
- Building an AI-driven deployment pipeline that replaces manual release sign-offs with frequent deploys, AI risk-scoring and automated error tracing.
- Leads and coaches a team of release managers and engineers.
- Owns the end-to-end release process, balancing speed with stability and compliance.
- Sets the roadmap for developer platform and release tooling, replacing manual steps with self-service workflows.
- Leads architecture of new platform services and runs blameless incident reviews.
-
Feb – Aug 2025
Enpal · Senior Backend Engineer · event-driven services with .NET, MongoDB and Azure
-
Sep 2024 – Feb 2025
Freelance · Backend Engineer (contract) · internal tools and data pipelines for early-stage startups, all projects delivered as scoped
-
Dec 2022 – Sep 2024
Senior BackendStaff Engineer
Staff Engineer
Feb – Sep 2024- Refactored application processing and introduced permission-based access, application volume up 15%.
- Delivered gRPC, Docker and Kubernetes microservices, system performance up 25%.
- Led cross-functional releases with 95% on-time delivery.
Senior Backend Software Engineer
Dec 2022 – Jan 2024- Designed gRPC APIs between backend systems, inter-service communication efficiency up 50%.
- Across both roles: optimized critical database queries by up to 1000×.
-
Sep 2021 – Dec 2022
Senior Software Engineer
Core services for image copyright protection.
- Improved image comparison accuracy and cut manual analysis overhead by 50%.
- Built a testing culture that brought 60% fewer production bugs.
-
Mar 2020 – Aug 2021
Backend Technical Lead
- Led a white-label fintech solution for BNL.
- Migrated to microservices and to bare metal for performance and cost gains.
- Integrated with EU financial systems.
-
May 2019 – Mar 2020
BillBeez · Backend Technical Lead · multichannel bill payments for small businesses, ACH and Payoneer integrations, secure REST APIs
-
Oct 2017 – May 2019
Thomas Cook · Fullstack Software Engineer · smart search and recommendations for personalized travel booking
-
Jan 2016 – 2017
Earlier career · 3 roles
- 2017Eze.tech · contract
- 2017Intersog · contract
- Jan 2016 – Apr 2017Leantegra · real-time location and analytics platform, Angular to React migration
04Selected projects
Things I build outside work, with the same care.
Illustration, not real data
Live
Migraine.Club
migraine.club
An evidence-first, privacy-first migraine diary that turns one-tap attack logs into doctor-ready summaries built on validated measures, with honest confidence labels and a dim mode for bad days.
- PWA
- Privacy-first
- HIT-6 · MIDAS · MSQ-21
Illustration, not a real verdict
Open source
Parley
parley.trading
An open-source, local-first terminal app where a council of six AI investor personas debates your stocks and returns a confidence-weighted BUY, SELL or HOLD verdict, dissent shown. Keyboard-first, educational only.
- Terminal UI
- Local-first
- Keyboard-first
Illustration, not real data
Open source · MIT
Claude Life OS
github.com/denysovkos/claude-life-os
An open-source Claude skill that turns Gmail, Google Drive and Supabase into a personal paperwork system that tracks documents, contracts and deadlines. Documented in 10 languages.
- Claude skill
- Gmail · Drive · Supabase
- 10 languages
05How I work
Four habits I bring to every team.
Blameless reviews
Incident reviews look at systems, not people, and every lesson becomes a lasting improvement.
Automate the manual step
A step someone has to remember is a step that gets replaced with self-service automation.
Trade-offs on paper
Options, risks and the reasoning behind a choice are written down before anything gets built.
Async first
Clear written context by default, so a globally distributed team can move without waiting for a meeting.
06Stack
Tools I reach for.
Languages
- TypeScript, JavaScriptexpert
- Goproficient
- C# / .NETproficient
- SQL
- Bash
Cloud and infra
- AWS, GCP, Azure
- Docker
- Kubernetes
- Terraform
- Pulumi
Data and messaging
- PostgreSQL
- MongoDB
- Kafka
- RabbitMQ
- gRPC
Practices
- Release management, CI/CD
- Database migrations
- Incident reviews
- System design, risk assessment
- Mentoring, code review
Writing and talks
Writing and talks
Testimonials