Learning path / Editorial roadmap
NightLens: system design decisions
A five-lesson course from requirements to controlled overload for a fictional telescope reservation service.
5 articles available · 5 proposed modules
Read at your own pace. This is a growing editorial plan, not a complete course or a progress tracker. Proposed topics have no lesson pages yet.
Explore the path
1 article available
Define the promise
Write a design brief for NightLens, including one-owner slot allocation, explicit SLO denominators, maintenance closures, and an offline-booking trade-off.
9 min read
Requirements and constraints: define an honest reservation
Write a design brief for NightLens, including one-owner slot allocation, explicit SLO denominators, maintenance closures, and an offline-booking trade-off.
1 article available
Size the workload
Convert an assumed telescope-session release into read and booking workloads, a latency budget, Little’s law estimates, and a bounded capacity experiment.
8 min read
Latency, throughput, and capacity: size the Monday release
Convert an assumed telescope-session release into read and booking workloads, a latency budget, Little’s law estimates, and a bounded capacity experiment.
1 article available
Protect ownership
Design NightLens slot locking, database constraints, scoped idempotency, read-after-write behavior, and a transactional outbox with explicit limits.
9 min read
Storage and consistency: make one reservation authoritative
Design NightLens slot locking, database constraints, scoped idempotency, read-after-write behavior, and a transactional outbox with explicit limits.
1 article available
Bound stale reads
Walk through an old-reader refill race and a source-anchored expiry policy for public telescope availability, with coalescing and bounded database fallback.
8 min read
Cache invalidation without selling a stale promise
Walk through an old-reader refill race and a source-anchored expiry policy for public telescope availability, with coalescing and bounded database fallback.
1 article available
Control failure
Finish the NightLens design with booking admission limits, honest unknown outcomes, isolated delivery, retry ownership, and recovery tests.
9 min read
Backpressure, timeouts, and retries during a reservation surge
Finish the NightLens design with booking admission limits, honest unknown outcomes, isolated delivery, retry ownership, and recovery tests.