Work

The track record behind the approach

HASHJOIN's methods come from its principal's work on large production database fleets. Summaries are below; the full write-ups live on mogilevskiy.dev.

These projects were built by Vitaliy Mogilevskiy as an employee of Slack and Auth0. They show the approach and the scale it's proven at; they are not HASHJOIN client engagements.

Slack · 2026 · Tech lead

OPS Framework: Claude Code as an on-call force multiplier

An AI-native operations framework for Slack's Vitess fleet. Claude follows codified runbooks with reasoning steps and confirmation gates, every command is logged with recall, and all parsing and analysis is handed to deterministic engines. This is the pattern HASHJOIN builds for clients.

25 codified runbooks · 15 production incident analyses in 2026, each reviewed by a human

Full case study on mogilevskiy.dev →
Slack · 2025–2026 · Architect

Sherlock: database forensics

Five-second snapshots of system, MySQL and vttablet state from every tablet, shipped to S3. When something breaks, you can rewind to the exact moment and see which query was burning the CPU.

11,000+ database servers · 5 s resolution vs 30 s scrapes

Full case study on mogilevskiy.dev →
Slack · Architect

Vitess upgrade control plane

Concurrent control-plane automation, in Go, to upgrade Slack's vttablet fleet across Vitess versions safely and repeatably.

Full fleet roll: 35 minutes, down from more than 2 days

Experience on mogilevskiy.dev →
Slack · Tier-0

TicketD provisioning and disaster recovery

Provisioning and disaster-recovery automation for a Tier-0 service, where downtime isn't an option.

Experience on mogilevskiy.dev →
Auth0 · Patent US11693748B2

RDS provisioning and decoupled maintenance

Automation that fully replaced Terraform for RDS provisioning and maintenance at Auth0, patented as a system for provisioning and decoupled maintenance of cloud database systems.

Read the patent →

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