Deprecation
Deprecation is the designation of a software feature, interface, component, version, or model as discouraged or no longer recommended while it remains available and may later be withdrawn.
Django in Action
Deprecation is the practice of announcing that an existing interface or field will be removed after a transition period.
- How it is used
- Manages backward-compatible database and API changes during long-lived production transitions.
- How deep it goes
- Details staged additions, data copying, readiness checks, and eventual removal, but not a general deprecation policy.
- Examples
- Uses Promoter name fields, replacement columns, and a Python data migration that populates full_name and common_name.
- What you can do after
- Operate staged Django migrations that replace fields without immediately breaking dependent applications or database consumers.
API Design Patterns
Deprecated is the API version lifecycle state in which a former current version remains available under current-version change restrictions but is scheduled for removal.
- How it is used
- Manages API version transitions while preserving a retiring version temporarily.
- How deep it goes
- Defines state transitions, change restrictions, removal timing, and a monthly timeline, but does not specify implementation mechanics.
- Examples
- Uses a monthly sequence in which versions progress through preview, current, deprecated, and deleted states.
- What you can do after
- Operate an API release cycle with a declared removal window and communicated deprecation schedule.
Learn Rust in a Month of Lunches
The deprecated attribute marks a Rust item as discouraged for use and causes the compiler to issue a warning when it is used.
- How it is used
- Marks outdated Rust items while allowing existing callers to continue compiling with a warning.
- How deep it goes
- Explains attribute syntax, warnings, notes, replacements, and IDE highlighting without covering removal workflows.
- Examples
- Uses deprecated_function and old_function calls, compiler warnings, a replacement note, and IDE strikethrough highlighting.
- What you can do after
- Apply #[deprecated] to guide callers toward a replacement while preserving compilation.
Read how Learn Rust in a Month of Lunches explains deprecation →
Automating API Delivery
The deprecated stability level denotes an API version that is scheduled for removal.
- How it is used
- Guides API lifecycle communication, consumer migration, and breaking-change policy before planned resource removal.
- How deep it goes
- Defines the notice, OpenAPI field, and sunset distinction, then applies them to automated breaking-change checks.
- Examples
- Uses a deprecated catalog endpoint, the Deprecated field, an x-sunset date, and oasdiff checks.
- What you can do after
- Operate/configure OpenAPI definitions and breaking-change checks for planned API migration and removal.
Effective Platform Engineering
Deprecation is the formal designation that a feature or interface remains temporarily available but should no longer be adopted and may later be removed.
- How it is used
- Coordinates platform upgrades and user migrations across many deploying teams.
- How deep it goes
- Explains promotion, deprecation, two-cycle compatibility, removal, event detection, and deployment scanning.
- Examples
- Uses Kubernetes admissionregistration API promotion and scans deployments for outdated apiVersions.
- What you can do after
- Diagnose outdated deployed APIs and coordinate migrations before a platform release removes compatibility.
Read how Effective Platform Engineering explains deprecation →
Related concepts
- commentconfigured by · A comment is text or markup designated by a format's syntax as an annotation or non-content rather than ordinary executable or data content.
- deleted statecontrasts with · Deleted is the API version lifecycle state in which a version has been removed and is no longer accessible.
- sunset strategycontrasts with · A sunset strategy is the planned discontinuation and shutdown of a software component, such as an API or subsystem, after its supported service period.
- api lifecyclepart of · An API lifecycle is the sequence of stages through which an API is designed, developed, tested, deployed, operated, evolved, and retired.
- warning messageproduces · A warning message is a nonfatal diagnostic or notification about a potentially problematic, risky, unusual, or undesirable condition that may require attention.
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