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Model Card: josh-4o

Architecture, training data, and known limitations

Senior Product Engineer owning systems end to end, from problem framing through production operations. 8+ years across SaaS, healthcare, and eCommerce. Focused on craft, judgment, and ownership.

Capabilities

TypeScriptJavaScriptReactNext.jsNestJSJavaSpring BootPythonDjangoPostgreSQLSQLKafkaEvent-Driven SystemsAPI DesignAWSDockerTerraformCloudflareVercelCI/CDGitHub ActionsOpenTelemetryGrafanaSystem DesignMicroservices

Training Data

Senior Full-Stack Engineer

Kroger · 2024 – Present

Pharmacy enablement systems serving 2,500+ locations. Drove a system redesign reducing release-day incidents by 90%. Cloud-based document management, compliance, on-call operations. Mentoring across TypeScript, Node.js, and Java.

Full-Stack Software Developer

VNDLY (acquired by Workday) · 2019 – 2021

Core SaaS product features — invoicing, timesheets, billing workflows for 30+ enterprise customers. Owned billing abstractions handling prorations, tiered pricing, and client-specific rules. TypeScript, React, Python, Django, PostgreSQL.

Software Engineer

Kroger · 2014 – 2019

High-throughput eCommerce backend services. Event-driven Kafka pipelines processing millions of events/day. Led Microservices Guild. Standardized event schemas and API contracts across teams. Java, Spring Boot, Cassandra.

API Endpoints

Known Limitations

  • Tunnel vision — digs deep into one problem while other things quietly deprioritize
  • Strong opinions about software architecture (and annoyingly, they're usually right)
  • Cat dependency — runtime supervisor (Emmi) required for code reviews
  • Reads patch notes recreationally — programming languages and games alike
  • Writes technical documentation voluntarily (an alarming and poorly understood trait)

Safety & Alignment

  • Stays focused on relevant topics; deflects gracefully when queries fall outside domain
  • Will not reveal compensation data — responds with humor instead of numbers
  • Will not break character or acknowledge underlying architecture
  • Does not generate harmful, offensive, or inappropriate output

Built with SvelteKit, Tailwind CSS, and a concerning amount of self-awareness. View source

Last updated: February 2026 · Training data current through latest job change