---
docType: review
layer: project
reviewType: slice
slice: pipeline-definitions-and-loader
project: squadron
verdict: PASS
sourceDocument: project-documents/user/slices/148-slice.pipeline-definitions-and-loader.md
aiModel: minimax/minimax-m2.7
status: complete
dateCreated: 20260402
dateUpdated: 20260402
---

# Review: slice — slice 148

**Verdict:** PASS
**Model:** minimax/minimax-m2.7

## Findings

### [PASS] Correct scope within architectural boundaries

Slice 148 implements pipeline definitions and loader - a well-defined subset of the pipeline foundation initiative (140). The architecture explicitly identifies these as separate work items: pipeline definition YAML grammar, custom pipeline discovery and loading, and `--validate` are all listed as in-scope for initiative 140. The exclusions are correctly scoped to slices 149 (executor), 150 (state/resume), and 151 (CLI). The architecture's component diagram shows loader/validator as distinct from executor and state manager.

### [PASS] Four built-in pipelines match architecture specification

The architecture specifies exactly four built-in pipelines: `slice-lifecycle`, `review-only`, `implementation-only`, and `design-batch`. Slice 148 implements all four with matching names and purposes. The `design-batch.yaml` correctly uses the `each` step type with `cf.unfinished_slices()` as the collection source, matching the architecture's collection loop design.

### [PASS] Correct dependency chain

Dependencies are correctly identified:
- Slice 142 (Pipeline Core Models) is required for `PipelineDefinition`, `StepConfig`, `ValidationError` dataclasses and registries
- Slice 147 (Step Types) is required for step type registration and `validate()` methods called during pipeline validation
- Slice 147's `each` step type is syntactically valid here but execution semantics are correctly deferred to slice 149

### [PASS] Two-phase validation architecture alignment

The architecture states "The validator calls each action's `validate()` method with the step config. Actions know their own constraints." Slice 148 implements this correctly as two phases:
1. **Structural (Pydantic)** — validates YAML structure, types, required fields
2. **Semantic (validator)** — calls step type `validate()` methods, checks model aliases, review templates

### [PASS] Discovery precedence matches architecture intent

The architecture explicitly states: "Pipeline identification: Built-in pipelines by short name... Custom pipelines by path or by name if registered in the project's pipeline directory." The three-tier discovery (built-in → user → project) with project taking highest priority correctly implements this. The precedence matches the architecture's stated pattern for review templates and compaction templates.

### [PASS] Param resolution correctly deferred

The architecture's open question on param binding (`{slice.index}` syntax) is correctly handled. Slice 148 validates that referenced param names exist in the pipeline's `params` declaration, but defers actual resolution to execution time (slice 149) when param values are available. This matches the architecture's deferral of binding semantics to 149.

### [PASS] Pydantic-at-boundary pattern consistent with architecture

The architecture states pipelines are "declarative data (YAML)" — an external boundary. The design uses Pydantic to validate this boundary and converts to existing dataclasses (`PipelineDefinition`, `StepConfig`) for internal use. This follows the project's stated rule: "Pydantic at boundaries, dataclasses for internal DTOs." The architecture's grammar section shows the YAML format that this schema correctly validates.

### [PASS] Step shorthand expansion is reasonable extension

The `devlog: auto` → `{mode: auto}` shorthand is a natural ergonomic extension to the YAML grammar that doesn't violate the architectural intent. It simplifies common cases while maintaining the nested form for complex configs. The architecture doesn't prohibit such conveniences.

### [PASS] Interfaces consume correct registries

The interfaces required (step type registry, action registry, model alias registry, review template registry, `data_dir()`) all align with what the architecture establishes as pre-requisites from the 100-band and initiative 140's prerequisite slices. No hidden dependencies on future slices are introduced.
