Koko Development

Use this skill when working on the Koko Elixir project — the BEAM co-resident agent alongside joelclaw.

When to Use

• Building new GenServers, supervisors, or event handlers in Koko
• Implementing workloads (health pulse, event digest, shadow executor)
• Wiring Koko to new Redis channels or joelclaw events
• Debugging OTP supervision trees or process crashes
• Comparing Koko shadow results against TypeScript equivalents

Triggers: koko, elixir agent, beam, otp, shadow executor, koko workload, koko event, mix

Project Location

• Repo: ~/Code/joelhooks/koko (github.com/joelhooks/koko)
• Host: Overlook (Mac Mini M4 Pro), accessible via ssh joel@panda
• AGENTS.md: Full context in repo root

ADR Awareness

Always check relevant ADRs before implementing. Koko's architecture is ADR-driven.

Before adding a new workload: Check ADR-0117 for the workload plan and ADR-0118 for shadow execution patterns.

Before changing Redis integration: Check ADR-0116 for the bridge protocol and phase boundaries.

Before any architectural change: Propose or update an ADR in ~/Vault/docs/decisions/.

Key Constraints

1. Koko is read-only (Phase 1). PubSub observer only. No LPUSH drain, no authoritative writes.
2. Shadow results only. Write to joelclaw:koko:shadow:<function> in Redis or local files. Never to Typesense, Todoist, gateway, or any production state.
3. If Koko crashes, nothing breaks. The TypeScript stack doesn't depend on it.
4. Redis at localhost:6379 — k8s NodePort on Overlook.

Development Commands

# Run
cd ~/Code/joelhooks/koko
mix deps.get
mix run --no-halt

# Test
mix test

# Interactive
iex -S mix
Koko.events_seen()

# Format
mix format

# Remote (from another machine)
ssh joel@panda "cd ~/Code/joelhooks/koko && mix run --no-halt"

OTP Patterns to Follow

• One GenServer per concern — health checker, event accumulator, shadow runner are separate processes
• Supervisor strategy: one_for_one unless processes are coupled (then rest_for_one)
• Pattern match event types in handle_info — don't use if/else chains
• Use Logger.info("[koko]") prefix for all log output
• Crash early — let supervisors handle recovery, don't defensive-code around failures

Implementation Phases

Phase 1: Passive Observer (current)

• Subscribe to joelclaw:gateway:events via PubSub ✅
• Log and classify events ✅
• Next: Add health pulse GenServer (Workload 1 from ADR-0117)

Phase 2: Dedicated Channel

• Create joelclaw:koko:events for claimed work
• TypeScript fans out to Koko: LPUSH joelclaw:koko:events <payload>
• Koko writes results to joelclaw:koko:results

Phase 3: Shadow Executor

• Mirror select Inngest functions as Koko GenServers
• Same inputs, parallel execution, compare results
• Shadow log at joelclaw:koko:shadow:<function>

Phase 4: Graduation

• Koko handles a workload more reliably than TypeScript
• Survived 30 days without manual intervention
• DX is enjoyable