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Module Dependencies & API Surface

Detailed static-analysis report for module dependencies & api surface.

Source: codebase scan · 2026-05-07

Executive summary

Costco Android has 56 modules (1 app + 22 features + 30 shared + 3 core/lib). The graph is densely connected — features import 15-24 shared modules each — and the public-API discipline of those shared modules is poor: shared/sdui exposes ~209 public top-level declarations with only 0-2% marked internal. Three shared modules (util, blankutil, common) have overlapping responsibilities. feature/savings appears to be a candidate for consolidation.

Module fan-in (most-depended-upon shared modules)

These are the modules every feature touches. Changes ripple far.

Shared module	Fan-in (dependents)	Risk
`shared/storage`	20	High — any change touches everything
`shared/statemanagement`	18	High
`shared/common`	14	High
`shared/ui`	13	High
`shared/pallet`	7	Medium

Heavy-coupled features (highest fan-out)

Feature module	Shared deps	Notes
`feature/account`	24	Couples to auth, data, featurehelper, sdui, security, geofence
`feature/discover`	16
`feature/warehouse`	15
`feature/dmc`	15

Findings

HIGH

Overlapping shared utility modules

shared/util (8 lines, depends on core/core + shared/storage) and shared/blankutil (UI-leaning utilities) and shared/common (general utilities) have unclear boundaries. New utility code likely lands in the closest module by accident.

Recommendation: Merge into a single shared/util module with sub-packages (util/text, util/time, util/format, util/ui). Run a one-time package move + internal sweep to firewall implementation details.

HIGH

Public API leaks in shared modules

Module	Public decl.	Internal decl.	Encapsulation
`shared/sdui`	~209	~0-2	CRITICAL <1%
`shared/auth`	139	11	MEDIUM 8%
`shared/common`	86	3	HIGH 3.5%
`shared/data`	11	2	PASS 18%

Recommendation: Define each module's public surface explicitly (a top-level api/ package). Mark everything else internal. Use Kotlin's -Xexplicit-api=strict compiler flag on shared modules.

MEDIUM

Possibly orphan module: `feature/savings`

Only depends on shared/translation, only consumed by feature/warehouse. Either deprecate or absorb into feature/warehouse.

Recommendation: Confirm with product whether feature/savings still ships separately; if not, retire the module.

MEDIUM

Heavy feature coupling

feature/account imports 24 shared modules. Changes anywhere in shared/* have a high probability of forcing recompiles or bugs in Account.

Recommendation: Introduce module-level interfaces that account depends on (anti-corruption layer). Convert direct imports of shared/sdui implementation classes into interface-only imports.

INFO

No dependency-graph artifact in CI

Modularization at this scale benefits from a generated module graph in CI to detect new cycles and unintended dependencies.

Recommendation: Add the kotlinx-dataframe-driven dependency-graph Gradle plugin (or Ben Mansfield's module-graph-assert) to generate a Mermaid graph per build and fail PRs that introduce new cycles.

Costco Android · Code Review Report · Generated 2026-05-07 · 626 machine-curated findings