Twenty guides in four topics, newest first. Each topic page suggests a reading order: multi-tenant architecture, billing and entitlements, security and identity, and operations. Guides with a runnable program are also listed on the labs page.
Attributing shared cloud cost to tenants is a set of choices. A worked lab shows one tenant's margin moving from 54% to -245% depending only on the allocation rule.
Host the status page outside your failure domain, probe what customers actually do, and measure availability as the contract defines it. A lab finds a gap in a common credit table.
Why one tenant's batch delays everyone in a shared queue, how deficit round-robin fixes it, and a lab in which a commonly published DRR dispatcher never served a second tenant.
Put the tenant ID on traces and logs, keep it out of metric labels, and know that baggage does not reach your spans by itself, as a Go lab with OpenTelemetry shows.
Which PostgreSQL changes block reads or writes, why a fast ALTER TABLE can stall an application for minutes, and how to stage column changes safely.
When roles are enough, when to add attribute rules, how customers can define roles, and a lab that parses and tests a tenant-aware OPA policy in Rego v1.
A hash chain stored next to the data proves consistency, not integrity. A lab tampers with a 1,000-record chain six ways and shows what external checkpoints add.
The SSO bugs that cause incidents happen after the library says 'valid'. How to link logins to users by issuer and subject, map roles, and end access when people leave.
Short access tokens and rotating refresh tokens only protect you if rotation is atomic. A lab shows a read-then-write store missing about 72% of simultaneous token replays.
