Core System Architecture Part 128 — Anonymous Network Product Lifecycle Governance, Capability Evolution, Backward Compatibility, Migration, Deprecation, Sunset & Privacy-Preserving End-of-Life Architecture
SIAR — Secure, Local-First, Multi-Transport Communication Platform
Series: Core System Architecture
Part: 128
Status: Architecture specification
Primary language: Rust
Builds on: Core System Architecture Parts 52, 57, 67, 83, 99, 107–108, 122–127
Primary purpose: define SIAR's product-lifecycle architecture for post-GA evolution, backward compatibility, compatibility promises, migration contracts, replacement capabilities, protocol/client retirement, deprecation, sunset, end-of-life (EOL), data portability, archival obligations, rollback boundaries, lifecycle evidence, and privacy-preserving product retirement.
1. Purpose
A capability is not finished when it reaches General Availability.
Every production feature eventually changes:
protocols evolve
dependencies disappear
clients age
storage formats migrate
products merge
capabilities become obsolete
security requirements tighten
A mature platform must answer:
How long is compatibility promised?
How is a breaking change introduced safely?
How does a replacement capability take over?
What happens to old data?
What happens to offline clients?
When may support end?
What evidence proves a capability is safe to retire?
How are users prevented from being trapped?
The governing principle is:
SIAR product lifecycle governance should make evolution explicit, compatible where promised, migratable where necessary, reversible where feasible, and honest about deprecation and end-of-life—without using user profiling, forced lock-in, or opaque telemetry to justify retirement.
2. Architectural Position
GENERAL AVAILABILITY
│
▼
MATURE
│
┌────────────┼────────────┐
│ │ │
EVOLVE REPLACE MAINTAIN
│ │ │
└────────────┼────────────┘
▼
DEPRECATED
│
▼
MIGRATION WINDOW
│
▼
SUNSET
│
▼
END-OF-LIFE
│
▼
RETIRED
3. Core Separation
Keep distinct:
deprecation
sunset
end-of-support
end-of-life
retirement
removal
migration
replacement
4. Non-Goals
Part 128 does not create:
forced lock-in
surprise removals
user engagement-based EOL
developer performance scoring
silent compatibility breakage
5. Lifecycle State
#![allow(unused)] fn main() { pub enum ProductLifecycleState { GeneralAvailability, Mature, EvolutionPlanned, ReplacementAvailable, Deprecated, SunsetScheduled, EndOfSupport, EndOfLife, Retired, } }
6. No Direct GA→Retired
Hard rule.
7. Lifecycle Record
#![allow(unused)] fn main() { pub struct CapabilityLifecycleRecord { pub capability: CapabilityId, pub state: ProductLifecycleState, pub effective_at: Timestamp, pub replacement: Option<CapabilityId>, } }
8. Historical Lifecycle Immutable
Hard rule.
9. Lifecycle Transition Request
#![allow(unused)] fn main() { pub struct LifecycleTransitionRequest { pub capability: CapabilityId, pub from: ProductLifecycleState, pub to: ProductLifecycleState, pub evidence: Vec<EvidenceRef>, } }
10. Transition Policy
#![allow(unused)] fn main() { pub trait ProductLifecyclePolicy { fn allowed( &self, from: ProductLifecycleState, to: ProductLifecycleState, ) -> bool; } }
11. Hard rule.
12. Capability Evolution
Evolution may change:
behavior
protocol
storage format
API
security policy
privacy semantics
13. Evolution Class
#![allow(unused)] fn main() { pub enum CapabilityEvolutionClass { CompatibleEnhancement, BehavioralChange, SchemaChange, ProtocolChange, SecurityTightening, Replacement, BreakingChange, } }
14. Hard rule.
15. Evolution Intent
#![allow(unused)] fn main() { pub struct CapabilityEvolutionPlan { pub capability: CapabilityId, pub class: CapabilityEvolutionClass, pub target_release: ReleaseId, pub migration: Option<MigrationPlanId>, } }
16. Backward Compatibility
Explicit promise.
#![allow(unused)] fn main() { pub enum BackwardCompatibilityPromise { None, BestEffort, LimitedWindow(Duration), Stable, LongTermStable, } }
17. Hard rule.
18. Compatibility Surface
#![allow(unused)] fn main() { pub enum CompatibilitySurface { Api, WireProtocol, PersistentData, Configuration, Cli, PluginInterface, BackupFormat, } }
19. Compatibility Contract
#![allow(unused)] fn main() { pub struct CompatibilityContract { pub capability: CapabilityId, pub surface: CompatibilitySurface, pub promise: BackwardCompatibilityPromise, } }
20. Hard rule.
21. No Implicit Compatibility Promise
Hard rule.
22. Breaking Change
A change is breaking if it invalidates a promised surface.
23. Hard rule.
24. Breaking Change Requirements
Must include:
impact analysis
migration path
communication plan
sunset timeline
rollback/forward plan
25. Hard rule.
26. Protocol Evolution
Part 52.
27. Protocol Version State
#![allow(unused)] fn main() { pub enum ProtocolVersionLifecycle { Current, Supported, Deprecated, SunsetScheduled, Unsupported, } }
28. No Silent Unsupported Version Drop
Hard rule.
29. Version Negotiation
Must authenticate capabilities/version.
30. Hard rule.
31. Old Client Compatibility
Policy-defined window.
32. Hard rule.
33. Client Version Support
#![allow(unused)] fn main() { pub struct ClientSupportWindow { pub platform: PlatformClass, pub minimum_supported: Version, pub recommended: Version, pub end_of_support: Option<Timestamp>, } }
34. Hard rule.
35. Offline Client Consideration
Local-first clients may remain offline for long periods.
36. Migration must tolerate delayed reconnect.
37. Hard rule.
38. Reconnect Migration
Old client reconnect flow:
authenticate
negotiate supported protocol
determine migration requirement
sync safe state
upgrade/guide
39. No Data Destruction On Old-Client Reconnect
Hard rule.
40. Persistent Data Evolution
Schema changes require migration contracts.
41. Migration Contract
#![allow(unused)] fn main() { pub struct MigrationContract { pub migration: MigrationPlanId, pub from_schema: SchemaVersion, pub to_schema: SchemaVersion, pub reversibility: MigrationReversibility, } }
42. Migration Reversibility
#![allow(unused)] fn main() { pub enum MigrationReversibility { Reversible, ConditionallyReversible, ForwardOnly, } }
43. ForwardOnly Requires Stronger Readiness
Hard rule.
44. Migration Preconditions
backup/recovery verified
capacity available
compatibility window known
rollback boundary understood
45. Hard rule.
46. Expand-Migrate-Contract
Preferred for live schema evolution.
47. Hard rule.
48. Dual Read / Dual Write
Temporary compatibility strategy.
49. Must be time-bounded.
50. Hard rule.
51. Migration State
#![allow(unused)] fn main() { pub enum MigrationState { Planned, Ready, Running, DualCompatibility, Cutover, Verifying, Completed, RolledBack, Failed, } }
52. No Completed Before Verification
Hard rule.
53. Data Version Marker
Explicit.
54. Hard rule.
55. Data Downgrade
Only if reversibility proven.
56. Hard rule.
57. Backup Compatibility
Older backup formats may need import support.
58. Hard rule.
59. Backup Format Support Window
#![allow(unused)] fn main() { pub struct BackupFormatSupport { pub format: BackupFormatVersion, pub import_supported_until: Timestamp, } }
60. Hard rule.
61. Configuration Evolution
Config schema versioned.
62. Auto-migration allowed only if deterministic.
63. Hard rule.
64. Config Deprecation
Warn before removal.
65. Hard rule.
66. API Evolution
Public API deprecation requires:
replacement
timeline
migration guidance
67. Hard rule.
68. Plugin Interface Evolution
Part 24/68.
69. Plugin compatibility scoped by declared interface version.
70. Hard rule.
71. Replacement Capability
#![allow(unused)] fn main() { pub struct CapabilityReplacement { pub old: CapabilityId, pub new: CapabilityId, pub parity: ReplacementParity, } }
72. Replacement Parity
#![allow(unused)] fn main() { pub enum ReplacementParity { Partial, FunctionalEquivalent, Superset, } }
73. No "Replacement Available" Without Declared Gaps
Hard rule.
74. Replacement Readiness
Replacement must be at sufficient maturity.
75. Hard rule.
76. Replacement Migration
Users/tenants need clear path.
77. Hard rule.
78. No Forced Migration Before Replacement Ready
Hard rule.
79. Deprecation
Deprecation means:
still usable
discouraged for new use
replacement/migration available or planned
support timeline known
80. Hard rule.
81. Deprecation Record
#![allow(unused)] fn main() { pub struct DeprecationRecord { pub capability: CapabilityId, pub deprecated_at: Timestamp, pub sunset_not_before: Timestamp, pub replacement: Option<CapabilityId>, } }
82. Hard rule.
83. Minimum Deprecation Window
Policy-driven.
84. Security Emergency Can Shorten
Hard rule.
85. Sunset
Sunset means:
new adoption blocked
migration strongly required
service removal scheduled
86. Sunset Record
#![allow(unused)] fn main() { pub struct SunsetPlan { pub capability: CapabilityId, pub sunset_at: Timestamp, pub migration_deadline: Timestamp, pub retirement_at: Timestamp, } }
87. Hard rule.
88. End Of Support
Support ends before full retirement in some cases.
89. Hard rule.
90. End Of Life
At EOL:
no new fixes except critical transition/security cases
migration/export remains where promised
91. Hard rule.
92. Retirement
Retirement means capability no longer active in supported product.
93. Hard rule.
94. Retirement Preconditions
migration complete or explicit remaining exception
data obligations resolved
replacement/exit path provided
runtime references removed
support/docs updated
95. Hard rule.
96. Data Portability
Before retirement, user/tenant-owned data must remain exportable as promised.
97. Hard rule.
98. Export Format
Portable, documented, versioned.
99. Hard rule.
100. No Proprietary Lock-In As Exit Strategy
Hard rule.
101. Data Deletion
Retirement must define deletion timing.
102. Hard rule.
103. Deletion State
#![allow(unused)] fn main() { pub enum LifecycleDataDisposition { Migrated, Exported, Deleted, ArchivedByPolicy, } }
104. Hard rule.
105. Archival
Only where retention policy requires.
106. Hard rule.
107. Cryptographic Erasure
Part 67.
108. Hard rule.
109. Orphan Data
No forgotten tables/blobs/indexes after capability retirement.
110. Hard rule.
111. Data Inventory Check
Part 106/123.
112. Hard rule.
113. Capability Runtime Reference
#![allow(unused)] fn main() { pub struct CapabilityRuntimeReference { pub capability: CapabilityId, pub deployment: DeploymentId, pub active: bool, } }
114. Retirement Requires Zero Active Required References
Hard rule.
115. Service Dependency Removal
Reverse dependency scan.
116. Hard rule.
117. Protocol Retirement
Requires:
no supported clients depend
no active federation peer depends unless scoped exception
migration complete
118. Hard rule.
119. Federation Compatibility
Part 58.
Peer support window explicit.
120. Hard rule.
121. Cross-Domain Sunset
No unilateral silent protocol break.
122. Hard rule.
123. Tenant-Specific Migration
Managed tenants may have negotiated windows.
124. Does not weaken platform hard security floor.
125. Hard rule.
126. Security-Driven Sunset
Critical vulnerability may force accelerated retirement.
127. Still provide:
safe migration
export
communication
where possible.
128. Hard rule.
129. Privacy-Driven Sunset
If capability cannot meet privacy floor, restrict/retire.
130. Hard rule.
131. Reliability-Driven Sunset
Repeated systemic failure may trigger replacement.
132. Part 120/121 integration.
133. Hard rule.
134. Cost Is Not Sole Retirement Reason
Hard rule.
135. Sustainability Is Not Sole Retirement Reason
Hard rule.
136. End-Of-Life Decision
#![allow(unused)] fn main() { pub struct EndOfLifeDecision { pub capability: CapabilityId, pub rationale: EndOfLifeRationale, pub evidence: Vec<EvidenceRef>, } }
137. Rationale
#![allow(unused)] fn main() { pub enum EndOfLifeRationale { SecurityUnsustainable, ReliabilityUnsustainable, DependencyEndOfLife, ReplacementComplete, ProtocolObsolete, OperationalBurden, ProductConsolidation, } }
138. Hard rule.
139. Evidence Required
Hard rule.
140. No Adoption-Based Auto-Sunset
Hard rule.
141. Low Usage Can Inform Planning
But not replace technical/data/user-obligation review.
142. Hard rule.
143. Lifecycle Communication
Need:
internal operators
developers/integrators
managed tenants
end users if applicable
144. Hard rule.
145. Communication Timeline
deprecation notice
migration reminders
sunset reminder
final EOL notice
146. Hard rule.
147. No Dark Patterns
Do not coerce migration through misleading UI.
148. Hard rule.
149. User-Facing Messaging
Must state:
what changes
when
what user must do
what happens to data
where migration/export is available
150. Hard rule.
151. Offline Users
Need delayed-reconnect handling.
152. Hard rule.
153. Missed Sunset Notification
Reconnect flow still provides migration path.
154. Hard rule.
155. Accessibility
Migration/EOL notices accessible.
156. Hard rule.
157. Support Transition
Support team receives:
timeline
migration tooling
known issues
exception process
158. Hard rule.
159. Operational Transition
On-call/runbooks updated.
160. Hard rule.
161. Feature Flags
Flags may disable deprecated feature.
162. Flag ≠ lifecycle state.
163. Hard rule.
164. Lifecycle Exceptions
Temporary extension.
#![allow(unused)] fn main() { pub struct LifecycleException { pub capability: CapabilityId, pub scope: LifecycleExceptionScope, pub expires_at: Timestamp, pub rationale: ExceptionRationale, } }
165. Exception Scope
#![allow(unused)] fn main() { pub enum LifecycleExceptionScope { Tenant(TenantId), Region(RegionId), FederationPeer(FederationDomainId), Deployment(DeploymentId), } }
166. No Individual User Exception Baseline
Hard rule.
167. Hard Invariant
Exception cannot extend insecure/unacceptable state below platform floor.
168. Hard rule.
169. Exception Renewal
Fresh review required.
170. No perpetual extension.
171. Hard rule.
172. Migration Tooling
Provide:
dry run
progress
resume
verification
rollback where possible
173. Hard rule.
174. Migration Dry Run
#![allow(unused)] fn main() { pub struct MigrationDryRun { pub migration: MigrationPlanId, pub impacted_records: u64, pub estimated_duration: Duration, pub blocking_issues: Vec<MigrationIssue>, } }
175. No private content in dry-run summary.
176. Hard rule.
177. Migration Checkpoint
Durable state.
178. Hard rule.
179. Migration Resume
Idempotent.
180. Hard rule.
181. Migration Verification
#![allow(unused)] fn main() { pub struct MigrationVerification { pub migration: MigrationPlanId, pub source_count: u64, pub destination_count: u64, pub integrity_state: IntegrityState, } }
182. Counts are technical aggregate.
183. Hard rule.
184. Rollback Boundary
Some migration steps may cross point of no return.
185. Explicit.
186. Hard rule.
187. Forward Recovery
If rollback impossible, forward-fix path must exist.
188. Hard rule.
189. Protocol Downgrade
Never allow downgrade below security/privacy floor.
190. Hard rule.
191. Compatibility Test Matrix
#![allow(unused)] fn main() { pub struct CompatibilityTestMatrix { pub old_versions: BTreeSet<Version>, pub new_versions: BTreeSet<Version>, pub scenarios: Vec<CompatibilityScenario>, } }
192. Hard rule.
193. Compatibility Scenarios
old client/new server
new client/old server
mixed multi-device
offline old client reconnect
federation version skew
194. Hard rule.
195. Version Skew Policy
#![allow(unused)] fn main() { pub struct VersionSkewPolicy { pub max_client_skew: VersionDistance, pub max_server_skew: VersionDistance, } }
196. Hard rule.
197. Compatibility Evidence
Stored in Part 126 archive.
198. Hard rule.
199. Lifecycle Baseline
#![allow(unused)] fn main() { pub struct LifecycleBaseline { pub capability: CapabilityId, pub state: ProductLifecycleState, pub compatibility_contracts: Vec<CompatibilityContract>, pub migration_plan: Option<MigrationPlanId>, } }
200. Immutable per release.
201. Hard rule.
202. Release Binding
Every release pins lifecycle baseline.
203. Hard rule.
204. Historical Reconstruction
"What compatibility promise applied in release X?"
Core requirement.
205. Hard rule.
206. Knowledge Graph Integration
Part 123.
Trace:
capability
→ lifecycle
→ replacement
→ migration
→ protocol versions
→ tests
→ release
207. Hard rule.
208. Requirements Integration
Part 124.
Deprecation/removal may change requirement set.
209. Hard rule.
210. Assurance Integration
Part 125.
Migration/compatibility qualification required.
211. Hard rule.
212. Archive Integration
Part 126.
Lifecycle decisions/evidence archived.
213. Hard rule.
214. Product Readiness Integration
Part 127.
Replacement capability must meet readiness threshold.
215. Hard rule.
216. Architecture Governance
Part 122.
Breaking changes require ADR/design review.
217. Hard rule.
218. Risk Integration
Part 121.
Lifecycle transition surfaces migration/EOL risks.
219. Hard rule.
220. PIR Integration
Part 120.
Incident learning can accelerate replacement/sunset.
221. Hard rule.
222. Change Integration
Part 107.
Lifecycle transitions are governed changes.
223. Hard rule.
224. Release Integration
Part 108.
Release must satisfy active compatibility/lifecycle promises.
225. Hard rule.
226. Update Integration
Part 99.
Client upgrade enforcement only within published support policy.
227. Hard rule.
228. Account/Data Lifecycle Integration
Parts 67/83.
Capability retirement cannot resurrect deleted data or break deletion commitments.
229. Hard rule.
230. Backup/Restore Integration
Part 100.
Retired capability data may remain in old backup.
231. Restore must migrate or quarantine old format.
232. Hard rule.
233. Restore Anti-Resurrection
No re-enabling retired/insecure capability automatically.
234. Hard rule.
235. Federation Integration
Part 58.
Lifecycle policy advertised to peers.
236. Hard rule.
237. Plugin Ecosystem Integration
Part 24/68.
Plugin compatibility deprecation communicated.
238. Hard rule.
239. SDK Lifecycle
SDK version support window.
240. Hard rule.
241. API Client Generation
Old generated clients supported according to compatibility contract.
242. Hard rule.
243. CLI Lifecycle
Deprecated commands warn.
244. Removal requires replacement/documentation.
245. Hard rule.
246. Config Key Lifecycle
#![allow(unused)] fn main() { pub enum ConfigKeyLifecycle { Active, Deprecated, IgnoredWithWarning, Removed, } }
247. Hard rule.
248. No Silent Ignore Before Published Window
Hard rule.
249. Data Format Evolution
RON/Postcard schema versioning explicit.
250. Hard rule.
251. Postcard Compatibility
Never assume backward compatibility without explicit schema strategy.
252. Hard rule.
253. RON Human Config
Unknown/deprecated keys handled explicitly.
254. Hard rule.
255. JSON External Interop
Versioned externally.
256. Hard rule.
257. Lifecycle Decision Authority
#![allow(unused)] fn main() { pub enum LifecycleDecisionAuthority { ProductOwner, PlatformArchitecture, SecurityAssurance, PrivacyAssurance, ReliabilityAssurance, ReleaseEngineering, } }
258. Scoped authority.
259. No Single Person Can Override Hard Block
Hard rule.
260. Deprecation Approval
Requires product + technical authority.
261. Hard rule.
262. Accelerated Security Sunset
Requires security authority + migration/communication plan.
263. Hard rule.
264. Retirement Approval
Requires:
data disposition verified
runtime references zero
compatibility obligations completed
265. Hard rule.
266. Lifecycle Review
#![allow(unused)] fn main() { pub struct ProductLifecycleReview { pub capability: CapabilityId, pub current_state: ProductLifecycleState, pub target_state: ProductLifecycleState, pub migration_readiness: ReadinessState, pub compatibility_readiness: ReadinessState, pub data_disposition_readiness: ReadinessState, } }
267. Hard rule.
268. Lifecycle Decision
#![allow(unused)] fn main() { pub enum ProductLifecycleDecision { Advance, Hold, Regress, CancelSunset, } }
269. Hard rule.
270. Cancel Sunset
Allowed if evidence changes.
271. Hard rule.
272. Lifecycle Freshness
#![allow(unused)] fn main() { pub enum LifecycleEvidenceFreshness { Fresh, DueForReview, Stale, } }
273. Stale migration/compatibility evidence blocks retirement.
274. Hard rule.
275. Lifecycle SLOs
Examples:
deprecated capability has replacement/migration docs
sunset notices issued before deadline
migration failures below threshold
retired capability has zero runtime references
276. Hard rule.
277. Security SLO
0 unsupported insecure protocol re-enabled after sunset
0 retirement bypassing data sanitization
278. Privacy SLO
0 lifecycle decision based on covert user profiling
0 retirement process exposing private content
279. Failure Modes
surprise breaking change
permanent deprecation
replacement not ready
orphan data after retirement
old offline clients unable to recover
280. Surprise Breaking Change
Prevent with compatibility contract + release gate.
281. Hard rule.
282. Permanent Deprecation
Review deadlines.
283. Hard rule.
284. Replacement Not Ready
Delay forced migration.
285. Hard rule.
286. Orphan Data
Inventory/data-disposition gate blocks retirement.
287. Hard rule.
288. Offline Old Client
Reconnect migration path.
289. Hard rule.
290. EOL Reversal
Rare but possible before final retirement.
291. Requires new lifecycle decision.
292. Hard rule.
293. Testing
Need product-lifecycle testkit.
294. Test Scenarios
protocol deprecation
database schema migration
offline client reconnect after sunset
capability replacement
retirement with data export
295. Transition Test
GA→Retired direct transition rejected.
296. Compatibility Test
Stable API cannot break without governed breaking-change process.
297. Old Client Test
Supported old client still interoperates inside window.
298. Offline Reconnect Test
Old offline client can migrate without data loss.
299. Migration Test
Completed state requires integrity verification.
300. Forward-Only Test
Requires stronger backup/recovery evidence.
301. Replacement Test
Forced migration blocked if replacement below required maturity.
302. Sunset Test
New adoption blocked after sunset.
303. Retirement Test
Active runtime reference prevents retirement.
304. Data Test
Orphan data prevents retirement.
305. Restore Test
Old backup cannot silently resurrect retired capability.
306. Privacy Test
No user behavior segmentation needed for lifecycle decisions.
307. Federation Test
Peer version sunset does not silently break negotiated window.
308. Exception Test
Expired lifecycle exception stops extension.
309. Fuzzing
Fuzz:
lifecycle transitions
compatibility contracts
migration states
sunset plans
lifecycle exceptions
310. Property Tests
Properties:
capability can never retire while active required runtime references remain
hard security floor can never be weakened by lifecycle exception
historical lifecycle baseline can never mutate
replacement-dependent sunset can never force migration before replacement reaches required maturity
311. Formal Verification Targets
Strong candidates:
lifecycle state machine
migration state machine
compatibility window
sunset/exception expiry
312. Kani Candidate
transition/exception/runtime-reference invariants.
313. TLA+ Candidate
GA → deprecate → migrate → sunset → EOL → retire, including rollback/cancel sunset.
314. Loom Candidate
concurrent client reconnect + migration + sunset transition.
315. Performance
Lifecycle governance is control-plane work.
316. Migration hot paths separately benchmarked.
317. Hard rule.
318. Storage
Separate:
lifecycle records
compatibility contracts
migration plans
deprecation records
sunset plans
EOL decisions
lifecycle exceptions
data disposition receipts
319. No user/developer analytics warehouse.
320. Hard rule.
321. Partitioning
By:
capability
protocol
platform
release
lifecycle state
322. No person/user partition.
323. Hard rule.
324. Crate Layout
Recommended:
crates/
├── siar-lifecycle-core/
├── siar-capability-evolution/
├── siar-compatibility-policy/
├── siar-migration-governance/
├── siar-deprecation/
├── siar-sunset/
├── siar-eol/
├── siar-lifecycle-exceptions/
├── siar-lifecycle-observability/
└── siar-lifecycle-testkit/
325. siar-lifecycle-core
Owns:
ProductLifecycleState
CapabilityEvolutionClass
BackwardCompatibilityPromise
ProductLifecycleError
326. siar-capability-evolution
Evolution plans/replacements.
327. siar-compatibility-policy
API/protocol/data/config compatibility contracts.
328. siar-migration-governance
Migration state/checkpoints/verification.
329. siar-deprecation
Deprecation lifecycle/window.
330. siar-sunset
Sunset schedule/communications/gates.
331. siar-eol
End-of-support/EOL/retirement/data disposition.
332. siar-lifecycle-exceptions
Scoped time-bounded extensions.
333. siar-lifecycle-observability
Aggregate lifecycle health only.
334. siar-lifecycle-testkit
compatibility/migration/retirement/privacy tests.
335. Security, Privacy & Correctness Invariants
Mandatory:
1. Capability lifecycle state, compatibility promises, migration contracts, deprecation windows, sunset, EOL, and retirement are explicit versioned records and can never be inferred only from feature flags or code removal.
2. Backward compatibility is a declared contract by surface—API, wire protocol, persistent data, configuration, plugin interface, backup format—and breaking a promised surface requires governed migration and release evidence.
3. A capability cannot move directly from GA to Retired; deprecation, migration, sunset, data disposition, support transition, and retirement verification are distinct lifecycle stages.
4. Replacement-dependent migration cannot be forced before the replacement reaches the required product/readiness maturity and documented parity/gaps are understood.
5. Offline/local-first clients, delayed reconnects, mixed-version multi-device states, and federation version skew are first-class compatibility scenarios and cannot be ignored during sunset.
6. Migration completion requires integrity verification, durable checkpoints, resumability, and rollback/forward-recovery semantics appropriate to reversibility; forward-only migration receives stronger assurance.
7. Retirement cannot complete while required runtime references, unresolved data stores, backup/import obligations, active federation dependencies, or compatibility promises remain outstanding.
8. Lifecycle exceptions are scoped, time-bounded, reviewed, and cannot extend a capability below hard security/privacy/reliability floors or become permanent hidden support commitments.
9. Capability retirement preserves data portability, export, deletion, archival, and cryptographic-erasure obligations and cannot use proprietary lock-in or inaccessible formats as an exit strategy.
10. Lifecycle communications are truthful, accessible, sufficiently early, and explicit about behavior/data/migration impact; dark patterns and surprise removals are prohibited.
11. Lifecycle decisions use technical, support, security, privacy, reliability, compatibility, and obligation evidence and cannot be driven by covert user profiling, sensitive-segment analysis, or developer/product-owner scoring.
12. Product lifecycle governance integrates with product readiness, requirements, engineering assurance, assurance archives, architecture governance, risk/PIR, release/update control, backup/restore, data lifecycle, federation, plugin/SDK/API governance, and audit/compliance without creating an alternate route around platform trust.
336. Initial Production Scope
Implement first:
typed ProductLifecycleState
capability lifecycle registry
compatibility contracts by surface
client/protocol support windows
migration contracts/state machine
offline reconnect migration
backup-format compatibility
replacement parity/readiness checks
deprecation records/windows
sunset plans
EOL/retirement decisions
data disposition checks
runtime-reference checks
federation/plugin/API lifecycle hooks
lifecycle exceptions with expiry
release lifecycle baselines
assurance-archive integration
privacy-safe lifecycle dashboards
lifecycle testkit
Then add:
automated reverse-dependency retirement analysis
cross-version compatibility matrix generation
migration digital twins
temporal lifecycle graph
federation sunset negotiation tooling
portable migration bundles
formal sunset/retirement verification
337. Definition of Done
Part 128 is complete when:
- lifecycle states are typed/versioned;
- compatibility promises are explicit by surface;
- breaking changes require migration governance;
- old/offline clients have defined handling;
- migrations are resumable and verified;
- replacements have maturity/parity requirements;
- deprecation/sunset/EOL are distinct;
- data export/deletion/archival obligations are enforced;
- retirement requires zero blocking runtime/data/dependency references;
- lifecycle exceptions expire;
- historical lifecycle baselines are reconstructable;
- no user/developer profiling drives lifecycle decisions;
- compatibility/migration/privacy/fuzz/formal tests are specified.
338. Final Architecture
GENERAL AVAILABILITY
│
▼
EVOLUTION
│
┌─────────────┼─────────────┐
│ │ │
COMPATIBILITY MIGRATION REPLACEMENT
│ │ │
└─────────────┼─────────────┘
▼
DEPRECATION
│
▼
SUNSET
│
▼
END-OF-LIFE
│
▼
RETIREMENT
Lifecycle-governance safety model:
explicit compatibility contracts
+
versioned migration plans
+
offline-client handling
+
replacement readiness
+
deprecation windows
+
data portability/disposition
+
retirement verification
+
historical lifecycle evidence
not:
remove old behavior when convenient, break old clients silently, force users onto an unready replacement, and leave orphaned data behind
339. Final Principle
A trustworthy product lifecycle does not merely explain how a feature starts—it explains how that feature can change, migrate, and eventually end without breaking promises.
The correct model is:
declare compatibility
+
evolve deliberately
+
migrate safely
+
support delayed/offline clients
+
deprecate visibly
+
sunset predictably
+
preserve user data rights
+
verify retirement
+
never use lifecycle management as a mechanism for lock-in or surveillance
This architecture gives SIAR a privacy-preserving lifecycle foundation for capability evolution, compatibility, migration, deprecation, sunset, EOL, replacement, data portability, and retirement while preserving the anonymity, local-first, least-authority, product-readiness, engineering-assurance, and anti-surveillance guarantees established across Parts 34–127.