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+# ADR-0004: Whitelist Cloned Fresh on Every Build — No Caching
+
+**Status:** Accepted
+**Category:** PATTERN
+**Date decided:** Early on
+**Date documented:** 2026-05-12
+
+## Context
+
+`constructParam.groovy` checks several whitelists (sonar skip, multizone, AppConfig, CAC, non-develop PR deploy) on every build. Jenkins agents are long-lived processes that handle many builds sequentially. If the whitelist were cached in agent memory or on disk, a policy change (adding or removing a repo from a whitelist) would not take effect until the agent restarted or the cache expired.
+
+## Decision
+
+`getWhitelistedRepos()` clones `Meesho/whitelists` fresh from GitHub on every build invocation. No in-memory cache, no disk cache, no TTL — each build gets the current live state of the whitelist at that moment.
+
+## Alternatives Considered
+
+- **Cache with TTL (e.g., 5 minutes)**: Rejected because a DevOps engineer who merges a critical policy change (adding a repo to skip-sonar during an incident) would have to wait for the cache to expire — unacceptable for incident response.
+- **Cache per Jenkins agent restart**: Rejected for the same reason — agents can run for hours/days, making cache invalidation unpredictable.
+- **Webhook-triggered cache invalidation**: Not evaluated — the simplicity of a fresh clone was preferred over building an invalidation mechanism.
+
+## Consequences
+
+**Positive:**
+- Policy changes take effect on the very next build after the whitelist PR is merged — no devops-lib release required.
+- No cache invalidation complexity; the whitelist state is always authoritative.
+
+**Negative:**
+- Each build that checks a whitelist incurs a `git clone` of `Meesho/whitelists`. At high build throughput, this is measurable latency.
+- If `Meesho/whitelists` is temporarily unreachable (GitHub outage, network partition), all builds that check whitelists fail.
+
+**Neutral:**
+- Multiple whitelist checks in a single build (sonar + AppConfig + multizone) each clone the repo separately — there is no deduplication within a single build.
+
+## Constraints
+
+Incident response requirements made immediate policy enforcement non-negotiable. The extra clone latency was accepted as the cost of correctness.
+
+## Current Assessment
+
+**Still appropriate** — no changes needed.
+
+## Related Decisions
+
+- [ADR-0003: Policy Exceptions in Separate Whitelist Repo](0003-policy-exceptions-in-separate-whitelist-repo.md) — The whitelist repo this decision is about.
+
+## Notes
+
+- Key file: `src/com/meesho/utilities/constructParam.groovy:getWhitelistedRepos()`
+- **Never refactor this to cache across calls** — the fresh-clone behaviour is load-bearing for incident response. This is documented in CLAUDE.md under NEVER DO.