# workshop-engine/src

**Generated:** 2026-05-19
**Commit:** 28abc5d

Execution engine extracted from workshop-baker. Process management, package detection, resource isolation.

## STRUCTURE
```
src/
├── lib.rs             # Module declarations + 10+ convenience re-exports
├── error.rs           # ExecutionError + DependencyError + HasExitCode trait
├── types.rs           # ExecutionContext, ExecutionResult, Engine, etc.
├── child.rs           # ManagedChild + TokioChild process wrappers
├── command.rs         # CustomCommand builder
├── executor.rs        # Script execution
├── time.rs            # Duration parsing helpers
├── pm.rs              # PackageManager trait + detection
├── pm/                # Backends: apt, apk, dnf, pacman
├── upm.rs             # UserPackageManager trait
├── upm/               # Backends: rust (cargo), python (pip), go, custom
├── repology.rs        # RepologyEndpoint enum
└── repology/          # Package name resolution (local/)
```

## KEY EXPORTS
| Symbol | Type | Role |
|--------|------|------|
| ExecutionContext | struct | Pipeline context (task_id, username, env, etc.) |
| Engine | struct | Script executor (placeholder) |
| ExecutionError | enum | Error types with exit codes |
| HasExitCode | trait | Exit code protocol for all error types |
| ManagedChild | struct | Child process wrapper with managed lifecycle |
| TokioChild | struct | Tokio-based child process wrapper |
| CustomCommand | struct | Builder for command execution |
| PackageManager | trait | System package manager abstraction |
| UserPackageManager | trait | User-level package manager abstraction |
| RepologyEndpoint | enum | Package name resolution endpoint |
| ExecutionEvent | enum | Event stream (TaskStarted, OutputChunk, etc.) |
| ExecutionResult | struct | Command execution result (exit_code, stdout, stderr) |
| EventSender | type alias | `Option<mpsc::Sender<ExecutionEvent>>` |

## CONVENTIONS
- **Exit codes**: Centralized in `error.rs` — EXITCODE_OK=0 through EXITCODE_PRIV_DROP_FAILED=201
- **ExecutionContext**: Defaults to current directory, bash shell, non-privileged
- **PackageManagers**: Auto-detected via `os_info`, fallback chain (apt→apk→dnf→pacman)
- **Engine**: Currently a unit struct with `execute_script()` method
- **All errors implement HasExitCode**: Enables uniform error propagation up to CLI

## ANTI-PATTERNS
1. **Engine is a stub** — `types.rs:99` — `pub struct Engine;` with no fields, minimal implementation