Explainer

Explainer

Plain explanations of the billing, tenancy and auth concepts these posts assume.

14 posts · page 1 of 2

Explainer

What is a feature flag, and how long until flipping it reaches the user

A feature flag changes behaviour without a deploy. The part most definitions skip is how long the flip takes to reach a user, and which kinds of flag can live with the wait.

6 min read
Explainer

Bring your own Stripe, explained

Bring your own Stripe means you keep the Stripe account and the platform connects to it. What that changes: who the legal seller is, who owes the tax, and what it really costs.

7 min read
Explainer

What is a passkey, and which of the two kinds you just got

A passkey is a key pair your user's device holds and proves on your domain. A synced one and a device-bound one behave differently the day a phone dies, and the ceremony tells you which you got.

7 min read
Explainer

What is a SaaS backend, and which half of it is your product

A SaaS backend is the server side of a subscription product. What makes it a SaaS backend is not the stack but the account model it carries: tenant, permission, usage and subscription.

6 min read
Explainer

What are magic links, and what the click actually hands over

A magic link is a single-use URL emailed instead of a password. The token lives an hour. The session it buys lives thirty days, and that is the number worth arguing about.

8 min read
Explainer

Idempotency in billing, and why it matters

Idempotency in billing means a retried charge, usage event, credit debit or webhook takes effect once. Having a key is the easy part. What the key names is where double billing starts.

11 min read
Explainer

Metered vs seat-based billing: charge for people or for work

Seat-based billing charges per person with access; metered billing charges per unit of work. Pick by what grows when a customer gets more value.

8 min read
Explainer

What are entitlements in SaaS, and what a plan change does to each kind

In SaaS, an entitlement is what a customer's plan lets them do: a feature, a limit, a quota or a credit grant. The four look alike until the plan changes.

10 min read
Explainer

What is multi-tenancy, and why the tenant is whoever pays

Multi-tenancy is one app serving many customers with their data kept apart. The decision that costs you later is which object in your schema is the tenant.

8 min read
Explainer

What is RBAC, and where it leaks in a B2B SaaS app

RBAC grants permissions to roles and roles to people. In a B2B app the role sits on the workspace membership, and the leaks are in the defaults, not the matrix.

8 min read
Explainer

What is usage-based billing, and what it does to your invoices

Usage-based billing charges for what a customer consumed rather than for access. The definition is easy. Defending the number on the invoice is the actual product.

6 min read
Explainer

Database-per-tenant vs shared schema: the decision is about migrations, not isolation

Shared schema, schema-per-tenant or database-per-tenant. Everyone frames it as isolation versus cost. The real fork is how many times you run every migration.

5 min read

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