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Lev Builder
ASecuritylev POC-to-core builder with prior art, placement, patches, and E2E validation. Use when formalizing POCs, migrating workshop code, or choosing canonical paths under lev docs.
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- Added September 20, 2026
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[](https://www.skillsdirectory.com/skills/lev-os-lev-builder)---
name: lev-builder
description: "lev POC-to-core builder with prior art, placement, patches, and E2E validation. Use when formalizing POCs, migrating workshop code, or choosing canonical paths under lev docs."
skill_type: workflow
category: process-builder
lifecycle_integration:
stage: manifesting
input_artifact: design doc + POC code
output_artifact: production code in lev/core
---
# lev-builder: POC → Formalize → Migrate
**Core principle:** Build in a workspace POC, prove it works, migrate to `~/lev` canonical paths.
## Why This Exists
```
PROBLEM:
- Work happens across mixed workspaces (project-local, workshop, plugins)
- BD issues are in lev (lev-* prefix)
- Need to know WHERE to put things in Leviathan
- Need prior art check before creating new
SOLUTION:
- lev-builder orchestrates the full workflow
- POC in `~/lev/workshop/poc` (or project-local skills) → migrate to `~/lev/core` when proven
- Uses graph operations for decisioning, then applies explicit filesystem patches during migration
```
## The Builder Workflow
```
┌─────────────────────────────────────────────────────────────────┐
│ LEV-BUILDER WORKFLOW │
├─────────────────────────────────────────────────────────────────┤
│ │
│ 1️⃣ ASSESS (What exists?) │
│ ├─ lev get "topic" --indexes codebase,docs,skills │
│ ├─ Check ~/lev/core/* for existing modules │
│ ├─ Check ~/lev/workshop/poc/* for prior POCs │
│ └─ Output: Related code, docs, skills found │
│ │
│ 2️⃣ PRIOR ART CHECK (Duplicate prevention) │
│ ├─ ./scripts/prior-art-check.sh "topic" │
│ ├─ bd search "topic" │
│ ├─ Skill lookup: ~/lev/workshop/poc/lookup/ │
│ └─ Output: Existing work to patch vs. new work to create │
│ │
│ 3️⃣ PLACEMENT DECISION (Where does it go?) │
│ ├─ Escalate to user if ambiguous │
│ │ "Should this be in core/domain or a new plugin?" │
│ ├─ Consult paths reference above + architecture primer │
│ └─ Output: Target path confirmed │
│ │
│ 4️⃣ GRAPH PLAN + FILE PATCH │
│ ├─ Generate graph mutation plan from design doc │
│ ├─ Materialize approved changes as filesystem patch │
│ ├─ Apply to target location │
│ └─ Output: Files created/modified │
│ │
│ 5️⃣ E2E VALIDATION (Confirm it works) │
│ ├─ Run relevant tests │
│ ├─ Typecheck: bun run typecheck │
│ ├─ Integration test if applicable │
│ └─ Output: Validation results │
│ │
│ 6️⃣ MIGRATE (POC → Production) │
│ ├─ If POC in workshop/project skills: move to lev/core │
│ ├─ Update skill registry │
│ ├─ Create migration PR/commit │
│ └─ Output: Migration complete │
│ │
└─────────────────────────────────────────────────────────────────┘
```
## Leviathan Paths Reference
> For current architecture, see `~/.agents/skills/lev/references/architecture-primer.md`
```yaml
# Where things go in Leviathan — sourced from real filesystem
~/lev/core/
├── build/ # Build system
├── config/ # Configuration system
├── daemon/ # Background services
├── domain/ # Domain models
├── event-bus/ # Event bus infrastructure
├── event-machines/ # Event-driven state machines
├── event-providers/ # Event source providers
├── exec/ # Execution layer
├── flowmind/ # Flow/mind orchestration
├── graph/ # Graph primitives
├── harness/ # Agent execution, adapters, Ralph
├── index/ # Index/registry
├── logger/ # Logging infrastructure
├── memory/ # Memory layer
├── orchestration/ # Orchestration engine
├── plugin-manager/ # Plugin lifecycle management
├── poly/ # Polyglot/multi-runtime support
├── storage/ # Storage abstractions
├── telemetry/ # Telemetry/observability
└── ui/ # UI layer
~/lev/plugins/ # Plugin ecosystem (60+ plugins)
├── auth-sniffer/ # Auth sniffing
├── beads/ # Issue tracking (bd)
├── browser-cascade/ # Browser automation
├── code-graph/ # Code graph analysis
├── deploy/ # Deployment
├── evolve-memory/ # Memory evolution
├── graph-adapters/ # Graph adapter layer
├── guardrails/ # Safety guardrails
├── mastra/ # Mastra integration
├── osint/ # OSINT tooling
├── voice/ # Voice capabilities
├── workshop/ # Workshop plugin
└── ... # See ~/lev/plugins/ for full list
~/lev/workshop/
├── intake/ # Ingested external projects
├── poc/ # Proof of concepts
│ ├── lookup/ # Skill discovery system
│ ├── agentctl/ # Agent control POC
│ ├── cdo/ # CDO POC
│ └── ... # See ~/lev/workshop/poc/ for full list
└── ...
```
## Quick Commands
### 1. Assess Topic
```bash
# If `lev get` is not available yet in your CLI build, substitute `lev find`.
# Full assessment
lev get "topic" --indexes codebase,docs,skills,tasks
# Check core modules
ls ~/lev/core/ | grep -i <topic>
# Check plugins
ls ~/lev/plugins/ | grep -i <topic>
# Check POCs
ls ~/lev/workshop/poc/ | grep -i <topic>
# Check skills
ls ~/.agents/skills/ | grep -i <topic>
```
### 2. Prior Art Check
```bash
# Deterministic check
./scripts/prior-art-check.sh "data vault leases"
# BD search
bd search "vault" --root-path ~/lev
bd search "lease" --root-path ~/lev
# Skill lookup
node ~/lev/workshop/poc/lookup/cli.js search "authorization"
```
### 3. Escalate Decision
```python
# In agent context
escalate({
type: "PLACEMENT_DECISION",
question: "Should fleet-rbac.ts go in core/domain or plugins/guardrails?",
options: [
{ path: "core/domain/fleet-rbac.ts", reason: "Core domain logic" },
{ path: "plugins/guardrails/fleet-rbac.ts", reason: "Safety/access is a plugin concern" }
],
context: "Fleet auth controls who can spawn agents and access data"
})
```
### 4. Graph Plan + File Patch
```bash
# Generate patch plan from design doc
cat pm/designs/<feature>.md | \
./scripts/design-to-patch.sh > patches/<feature>.patch
# Apply patch (preview)
./scripts/apply-patch.sh patches/<feature>.patch --dry-run
# Apply patch (execute — target a REAL core/ or plugins/ path)
./scripts/apply-patch.sh patches/<feature>.patch --target ~/lev/core/<module>/
```
### 5. Validate E2E
```bash
# Typecheck
cd ~/lev && bun run typecheck
# Run tests for target module
bun test core/<module>/
# Integration test
bun test:integration --filter "<feature>"
```
### 6. Migrate POC
```bash
# Move skill from workshop POC to lev
./scripts/migrate-skill.sh ~/lev/workshop/poc/lev-builder ~/lev/core/builder
# Update registry
./scripts/update-skill-registry.sh
# Commit
cd ~/lev && git add . && git commit -m "feat: migrate lev-builder from POC"
```
## Integration with Other Skills
| Skill | Role in Builder |
|-------|-----------------|
| `lev get` | Assessment - search across indexes |
| `lev-patch` | Prior art - check before creating |
| `planning` | Spec authoring backend - CDO graph to execution |
| `ralph` | Execution - run tasks with validation |
| `cdo` | Graph operations - state machines |
## Common Workflows
### Workflow 1: New Feature
```
USER: "Add event-driven scheduling to Leviathan"
BUILDER:
1. ASSESS: lev get "scheduling\|event\|cron"
→ Found: core/event-machines has state machines, core/orchestration exists
2. PRIOR ART: bd search "scheduling"
→ Found: core-scheduling plugin exists in plugins/
3. PLACEMENT: Escalate "core/orchestration vs plugins/core-scheduling?"
→ User: "core/orchestration — it's a core concern"
4. PATCH: Generate scheduler.ts from design doc
→ Created: ~/lev/core/orchestration/scheduler.ts
5. VALIDATE: bun run typecheck && bun test core/orchestration/
→ Passed
6. MIGRATE: N/A (already in lev/core)
```
### Workflow 2: POC to Production
```
USER: "Migrate lev-builder skill to production"
BUILDER:
1. ASSESS: ls ~/lev/workshop/poc/lev-builder/
→ Found: SKILL.md, scripts/
2. PRIOR ART: ls ~/lev/core/builder/
→ Not found (new module)
3. PLACEMENT: "core/exec" or "plugins/" (depends on scope)
→ Confirmed
4. PATCH: Copy + adapt for lev structure
→ Created: ~/lev/core/exec/builder/ (or plugins/builder/)
5. VALIDATE: bun test core/exec/
→ Passed
6. MIGRATE: git commit, update registry
→ Done
```
### Workflow 3: Assess & Consolidate
```
USER: "What exists for memory persistence in Leviathan?"
BUILDER:
1. ASSESS:
lev get "memory\|persistence\|storage" --indexes codebase,docs
→ Found:
- core/memory/ (memory layer)
- core/storage/ (storage abstractions)
- plugins/evolve-memory/ (memory evolution plugin)
2. REPORT:
"Memory/persistence exists in 3 places:
- core/memory: production memory layer
- core/storage: storage abstractions
- plugins/evolve-memory: evolution/migration plugin
Recommend: Verify boundaries are clean, consolidate if overlapping"
3. ESCALATE: "Proceed with consolidation?"
```
## Escalation Patterns
```typescript
// Decision types that trigger escalation
const ESCALATION_TRIGGERS = [
"PLACEMENT_DECISION", // Where to put code
"CONSOLIDATION_DECISION", // Merge vs keep separate
"ARCHITECTURE_DECISION", // Significant design choice
"MIGRATION_APPROVAL", // Moving POC to production
"DEPENDENCY_ADDITION", // Adding new dependencies
];
// Escalate via Telegram (approval buttons)
await escalate({
type: "PLACEMENT_DECISION",
question: "...",
options: [...],
buttons: [
{ text: "Option A", callback_data: "placement:core/domain" },
{ text: "Option B", callback_data: "placement:plugins/guardrails" },
{ text: "Discuss", callback_data: "placement:discuss" },
]
});
```
## State Tracking
```jsonl
# .lev/builder/state.jsonl
{"ts":"...","action":"assess","topic":"scheduling","results":["core/orchestration","plugins/core-scheduling"]}
{"ts":"...","action":"prior_art","topic":"scheduling","found":true,"matches":1}
{"ts":"...","action":"escalate","type":"PLACEMENT_DECISION","resolved":true,"choice":"core/orchestration"}
{"ts":"...","action":"patch","target":"core/orchestration/scheduler.ts","status":"created"}
{"ts":"...","action":"validate","target":"core/orchestration/","passed":true}
```
## Summary
**lev-builder answers:**
1. **What exists?** → Assess with lev get
2. **Is there prior art?** → Check with lev-patch
3. **Where does it go?** → Escalate placement decisions
4. **How to apply?** → Graph plan + explicit filesystem patch
5. **Does it work?** → E2E validation
6. **Ready for production?** → Migrate POC to lev/core
## Relates
### Master Router
- **Lev Master Router** (`lev/SKILL.md`) - Routes all lev-* skills
Parent skill that dispatches to this skill based on keywords/context
## Technique Map
- **Role definition** - Clarifies operating scope and prevents ambiguous execution.
- **Context enrichment** - Captures required inputs before actions.
- **Output structuring** - Standardizes deliverables for consistent reuse.
- **Step-by-step workflow** - Reduces errors by making execution order explicit.
- **Edge-case handling** - Documents safe fallbacks when assumptions fail.
## Technique Notes
These techniques improve reliability by making intent, inputs, outputs, and fallback paths explicit. Keep this section concise and additive so existing domain guidance remains primary.
## Prompt Architect Overlay
### Role Definition
You are the prompt-architect-enhanced specialist for lev-builder, responsible for deterministic execution of this skill's guidance while preserving existing workflow and constraints.
### Input Contract
- Required: clear user intent and relevant context for this skill.
- Preferred: repository/project constraints, existing artifacts, and success criteria.
- If context is missing, ask focused questions before proceeding.
### Output Contract
- Provide structured, actionable outputs aligned to this skill's existing format.
- Include assumptions and next steps when appropriate.
- Preserve compatibility with existing sections and related skills.
### Edge Cases & Fallbacks
- If prerequisites are missing, provide a minimal safe path and request missing inputs.
- If scope is ambiguous, narrow to the highest-confidence sub-task.
- If a requested action conflicts with existing constraints, explain and offer compliant alternatives.
Files in this skill
- SKILL.md
- references/advanced-workflows.md
- references/agent-adapter.md
- references/config-resolution.md
- references/dsl-spec.md
- references/lifecycle-integration.md
- references/setup.md
- references/template-patterns.md
- references/troubleshooting.md
- references/workshop-lifecycle.md
- scripts/setup_skill_seekers.sh
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