TSM / CETIN
Senior backend and integration work on Kotlin/Java/Spring services, PostgreSQL-backed systems, B2B flows, PEW, NIP, change management and production rollout of new platform versions.
Senior Backend-heavy Full-stack Engineer · Team Lead
Pavel Kleisner
I build and steady the backend systems that keep real businesses moving.
Nine years across Kotlin, Java, Spring and PostgreSQL — from full-stack delivery to leading production rollouts, integrations and incident analysis. I like precise changes, honest communication and software that still makes sense two years later. I'd rather fix production than be right about it.
Near Prague · remote · CET
Primary stack
Kotlin · Java · Spring
PostgreSQL, Kafka-style messaging
Production rollouts
TSM 1.5 · 2.2 · 2.4
Lead on 2.2 / 2.4, core contributor on 1.5
Experience
9+ years
Backend, integrations, full-stack stints
Based in
Near Prague · CET
Open to remote collaboration
What I bring to the table
Usually the value isn't another abstraction layer. It's a change that survives real data, integrations, support and the next release.
Integrations
B2B APIs, process flows, message behavior, retries, logs and failure modes that only become visible after deployment.
Releases
Rolling new versions into real environments while watching compatibility, old data and operational risk.
Architecture
Small safe changes, clearly named rules and service boundaries. No ceremony around patterns.
Debugging
Incidents through logs, metrics, databases and domain context. Not random patches around symptoms.
War story · anonymised
The UUID that wasn't a UUID
When we rolled out the first platform version, the integration spec said themessageId would be a UUID. One partner started failing immediately. Their system was quietly parsing the ticket ID out of the oldticketId_timestamp format — even though the ticket ID sat right there in the message body.
The clean fix was on their side, but in a corporate setting that change would take months. So I adapted our side back to the old shape and kept production running. Sometimes the right call isn't the pure one — it's the one that doesn't break someone else at 2 a.m.
Core stack
Primary
KotlinJavaSpringPostgreSQLKafka
Also
KubernetesOracleAngularPython / DjangoAstroTypeScript
Experience snapshot
A quick map of the systems I've worked on. The longer version — including what I actually owned on each — lives on the projects page.
current focus
MNCP
Kotlin/Spring, Angular and database work around authentication, measuring batches, archives, exports and operational fixes.
ZIS
Enterprise Java and ZK/ZUL work across screens, controllers, services, DAO layers, imports, Excel processing and production bug fixes.
Interested in collaboration?
If you need a senior engineer for backend systems, integrations, production releases or long-term product development, email is the fastest channel.