Recommended expert

Christopher Gorski

Senior Software Engineer

Christopher Gorski
Warsaw, Poland

Experience

Apr 2024 - Present
1 year 10 months

Senior Software Engineer

Allegro

  • Re-platformed the checkout cluster to Spring Boot 3 (MVC) with Kafka + Outbox/Saga, halving hot-path p99 420 ms → 210 ms (-50%) at 6.5k rps; validated in Grafana + Datadog APM and k6 load runs.
  • Introduced Redis + Caffeine cache-aside for availability/pricing, cutting DB reads -38% and saving ≈$14k/quarter in IOPS; proven via RDS Insights, Redis INFO, and cost reports.
  • Delivered zero-downtime blue/green deploys (Argo Rollouts, PDBs, readiness gates) for pricing API, taking deployment failure rate 3.1% → 0.6% and MTTR 27 → 9 min; evidence in Argo + PagerDuty timelines.
  • Shipped OpenTelemetry traces + logs/metrics correlation across 12 microservices; cross-service debug time dropped 45 min → 12 min; measured in Jaeger/Tempo and on-call reports.
  • Frontend: migrated legacy catalog UI from AngularJS to Angular 17 micro-frontends and built a React promo-rules editor (module federation, RxJS query, React Hook Form); LCP p75 3.2 s → 1.9 s, CLS 0.14 → 0.04; verified by Lighthouse + Web Vitals.
  • Added feature-flagged A/B price rules (Unleash + Spring Boot starter) with Micrometer business counters; conversion on targeted SKUs +2.4%; experiment readout in internal experimentation platform.
  • GC and pool tuning (G1 → ZGC, Hikari), plus HTTP thread tuning; CPU -22%, container requests -18%, worth ≈$5.7k/month infra savings; shown in Kubernetes + Datadog dashboards.
Mar 2024 - Mar 2025
1 year 1 month

Senior Software Engineer

Artisan AI

  • Built a low-latency inference gateway (Spring WebFlux + Netty, gRPC) in front of GPU workers; p95 ~180 ms at 2.1k rps, 99.9% availability; validated via Prometheus SLOs, Grafana, k6.
  • Implemented RAG retrieval service (Java + pgvector + Redis Bloom) with re-rank; search F1 +13% and tail p99 520 ms → 260 ms; metrics from offline eval harness + APM traces.
  • Orchestrated async embeddings/batch jobs (Kafka, Spring Cloud Stream, Outbox/Inbox), eliminating duplicate work and lowering reprocessing costs -37%; confirmed by Kafka consumer lag + cost reports.
  • AI quality: added guardrails (prompt templates, input sanitization, semantic grounding, toxicity classifier) cutting hallucination rate -28% and policy violations -62%; measured by weekly eval set + human review.
  • Shipping/runtime: containerized models on Triton + KServe, GPU autobatching + dynamic concurrency; throughput +41% per A100 and unit cost -24%; numbers from Prometheus GPU/exporter + billing.
  • Security & compliance: mTLS, per-tenant quotas (Bucket4j + Redis), SBOM (Syft/Grype) + Cosign image signing; critical CVEs -92% in 2 quarters; trends from CI security gates.
  • Frontend: built a React admin console and Vue-based prompt/playground with latency charts, eval diff views, and feature flags; PR cycle time 3.4 → 2.1 days (-38%) and post-release integration bugs -41%; GitHub/CI analytics.
  • JVM footprint optimization (JLink, CDS, tiered compilation) and Alpine base; image size -48%, cold-start -35% for serverless workers; validated in registry stats + cold-start traces.
Oct 2021 - Feb 2024
2 years 5 months

DevOps Engineer

AioCare

  • Rolled out a Kubernetes platform (3 envs, 8 node pools) with Terraform + Helm + Argo CD, cutting deploy time 45 min → 7 min (-84%) and enabling ~20 prod releases/week; verified in Argo CD history and Jira releases.
  • Built progressive delivery (blue/green + canary 5%→25%→100%) on GitHub Actions → Argo Rollouts, reducing failed deploys by ~72% and MTTR 38 min → 11 min; confirmed via PagerDuty + Grafana incident timelines.
  • Introduced SLOs (p95 API < 250 ms, error budget 1%/30d) with burn-rate alerts; lifted API uptime to 99.95% over 12 months and cut MTTD 12 min → 3 min; Prometheus/Grafana dashboards as evidence.
  • Optimized cloud spend -28% YoY using HPA/VPA, spot nodes, storage lifecycle policies, and right-sizing; environment spin-up shrank 2 days → 2 hours with reusable Terraform modules; validated by Cost Explorer/Billing + CI timestamps.
  • Shipped end-to-end observability (OpenTelemetry traces, Prometheus metrics, Loki/ELK logs) and golden dashboards per service, lowering “unknown root cause” postmortems by ~60% and after-hours pages by ~50%; PagerDuty analytics + RCA tags.
  • Hardened SDLC for medical data: SBOM + image signing (Syft/Grype, Cosign), OPA/Gatekeeper policies, Vault/KMS secrets; reduced critical CVEs in images by >90% within 2 quarters; security scan trends used for proof.
  • Delivered DR runbooks and quarterly game-days achieving RPO ≤ 5 min and RTO ≤ 30 min via cross-region backups and infra-as-code restores; results documented in DR drill reports.
Jul 2016 - Sep 2020
4 years 3 months

Software Engineer

Spyrosoft

  • Designed, developed, and maintained enterprise and consumer-facing applications for multiple international clients, such as a fintech dashboard for BNP Paribas, an e-commerce platform for a retail client, and a healthcare management tool for a telemedicine startup; delivered scalable solutions using React, Angular, and Vue on the front end, with FastAPI, Django, Java, and Golang powering high-performance back ends, ensuring seamless integration, security, and excellent user experience.

Skills

Programming Languages:

  • Java
  • Typescript/javascript
  • Python
  • Go
  • Sql

Frameworks & Libraries:

  • Spring Boot 3 (Mvc & Webflux/netty)
  • Grpc
  • Micrometer
  • Jpa/hibernate
  • Reactor/rxjava
  • Fastapi/django (Prior)
  • Node.js (Nestjs/fusion.js)
  • React
  • Angular
  • Vue

Cloud & Infrastructure:

  • Aws (Lambda, S3, Ec2, Eks Etc)
  • Gcp
  • Docker
  • Kubernetes

Database Technologies:

  • Postgresql
  • Mongodb
  • Mysql
  • Firebase
  • Redis

Message Queues & Real-time Systems:

  • Rabbitmq
  • Kafka
  • Websocket
  • Firebase
  • Sns

Security & Compliance:

  • Oauth 2.0
  • Jwt
  • Ssl/tls
  • Gdpr

Devops & Ci/cd:

  • Gitlab Ci/cd
  • Jenkins
  • Travis Ci
  • Docker
  • Kubernetes
  • Aws Lambda

Testing Frameworks:

  • Junit
  • Mockito
  • Jest
  • Cucumber
  • Postman
  • Selenium

Version Control & Collaboration:

  • Git
  • Github
  • Gitlab
  • Bitbucket
  • Jira
  • Confluence

Monitoring & Logging:

  • Prometheus
  • Grafana
  • Aws Cloudwatch
  • Datadog

Languages

English
Advanced
Polish
Advanced

Education

Oct 2014 - Mar 2016

Lublin University of Technology

Master’s Degree in Computer Science · Computer Science · Lublin, Poland

May 2010 - Sep 2014

Lublin University of Technology

Bachelor’s Degree in Computer Science · Computer Science · Lublin, Poland

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