No nil slice returns

No nil map returns

No nil updated IDs slice

Capacity hint from input

No speculative overallocation

Named struct fields

var for zero-value locals

:= for non-zero locals

JSON test: empty slice not null

JSON test: empty map not null

Named booleans in CanAccess

Descriptive boolean names

No else after return in AssignPricingTier

Switch in HandleWebhookEvent

Switch default case

context.Context first

Options struct for SendNotification

Delivery options grouped

Default-then-override in AssignPricingTier

No ≥5 param function signatures

Variable init scope in if

strconv for int conversion

strings.Builder in Generate

No += in loop

fmt.Sprintf for float formatting

Internal helpers unexported

Minimal exported surface

Generic Contains function

Declaration order

Value params for small types

range over index loop

%q in error messages