Shared language for hard software ideas
Collect metaphors that make systems easier to explain.
Anyone can add a metaphor and tag the software concept it explains. Search updates live, and the front page doubles as the public archive.
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Explained for
API gateway
An API gateway is a front desk that routes visitors, checks badges, and keeps the hallways orderly.
Explained for
CI/CD
CI/CD is a conveyor belt with checkpoints, where every change rides the same line before it reaches customers.
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Caching
Caching is a pantry stocked with the ingredients your application grabs all day.
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Database indexes
A database index is the table of contents for your data; without it, every query starts at page one.
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Event sourcing
Event sourcing is a flight recorder for business state: you can rewind every change instead of guessing what happened.
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Feature flags
Feature flags are light switches behind the walls, so you can open a room without rebuilding the house.
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IDP; Identity and Service providers.
Imagine you are going to a club, and you are invited to the VIP lounge. You have your state issued id card with you.
The club owner doesn't want every bartender and VIP host to become an expert in detecting forged identity cards and passports from every country. Instead, they outsource that responsibility to a trusted security company at the entrance. The security company verifies identities once, according to agreed rules, and then issues trusted stamps that the rest of the club accepts.
So just outside the club there is a trustworthy security guard from a reputable company. They check your ID, make sure you are of age, and if you are part of the VIP guest list. If so you get a blue stamp for age verification and a red one for being on the VIP list.
When you enter the club, all you have to do is show the blue stamp, and when you want to enter the VIP lounge you show them the red stamp.
This way you don't have to reveal your name, nationality or age to the club hosts, only to the security guard. And the stamp tells the club employees that you are old enough and are on the VIP list. The club owner needs to trust that the security guard is doing the job properly and only accepts state issued id cards or passports, as agreed upon.
In this case, the club is the Service Provider, the security guard and the company they work for is the Identity Provider (IdP), and the state is the Authoritative Identity Source.
The stamps are Authentication Tokens or Claims.
Explained for
Legacy system changes
Changing a load-bearing rule in a legacy system is like rebuilding the floor while people are still walking on it.
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Observability
Observability is a glass cockpit for a distributed system: you fly by gauges, traces, and alerts instead of instinct.
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Queues
A job queue is an air traffic tower that spaces out background work so nothing collides.
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Zero-downtime deployments
A zero-downtime deployment is swapping train lines while passengers are still boarding, so the route changes without stopping the station.