GET /jwcastillo HTTP/2
host: github.com
x-role: performance engineer
x-location: Santiago, Chile
accept: k6, core-web-vitals, clean-architecture, test-first
x-also: AI agent tooling (Claude Code, Codex, OpenCode, Gemini CLI)I measure before I claim. I load test with k6, keep Core Web Vitals inside their budgets, design systems with Clean and Hexagonal Architecture, and audit AI agent skills with NVIDIA SkillSpector before sending the fixes upstream.
- k6 Prometheus remote-write output, Grafana's xk6 extension: built its Grafana dashboards, including the native histogram dashboard and status-code rate and Apdex panels (all 8 PRs). I also contributed to the TimescaleDB, InfluxDB and Dynatrace outputs.
- NVIDIA/SkillSpector#645: removed three classes of analyzer false positives from the agent skill scanner.
- wshobson/agents#765–#768: restricted CORS in the FastAPI template and made it run end to end, and brought the monorepo, end-to-end testing and Git workflow skills up to current tool behavior.
Every repository where my pull requests were merged, most recent first. A daily workflow refreshes this list and the waterfall above.
- didit-protocol/skills
- JuliusBrussee/caveman
- nucliweb/webperf-snippets
- wshobson/agents
- sickn33/agentic-awesome-skills
- NVIDIA/SkillSpector
- multica-ai/multica
- grafana-cold-storage/xk6-output-prometheus-remote
- grafana-cold-storage/xk6-output-timescaledb
- grafana/xk6-output-influxdb
- Dynatrace/xk6-output-dynatrace
- srperf/PDD
- grafana-cold-storage/k6-timescaledb-stack
- CityOfZion/neo-scan
- netlify/staticgen
- titoBouzout/Dictionaries
- malahierba-lab/chile-rut
- vova07/yii2-start-users-module
- vova07/yii2-start-blogs-module
- vova07/yii2-start-comments-module
- JayBizzle/Laravel-Migrations-Organiser
- k6-enterprise-framework: a TypeScript k6 load testing framework with a two-layer architecture, observability and multi-client isolation.
Editor LazyVim · multiplexers tmux and Zellij · agents Claude Code, Codex, OpenCode and Gemini CLI.
Need a load test, a Core Web Vitals budget or a second look at an agent setup? Say hi on LinkedIn.
The waterfall is a metaphor: the timings are illustrative, the links are real.