diff --git a/CLAUDE.md b/CLAUDE.md
index 5b60dac..97b979b 100644
--- a/CLAUDE.md
+++ b/CLAUDE.md
@@ -62,7 +62,7 @@ src/
 
 ## Architecture
 
-Each module has a single responsibility. No classes — only exported async functions.
+Each module has a single responsibility. No classes — only exported functions (async when they do I/O, sync when pure).
 
 **Session flow for `sandlot new <branch>`:**
 1. `git.createWorktree()` → creates worktree at `~/.sandlot/<repo>/<branch>`
diff --git a/src/commands/config.ts b/src/commands/config.ts
index 3c8565d..6ef89c5 100644
--- a/src/commands/config.ts
+++ b/src/commands/config.ts
@@ -27,6 +27,6 @@ export async function action(args: string[]) {
 
   let normalized: string
   try { normalized = config.validateMemory(rest[0]) } catch { return die("Must be a number followed by G or M, minimum 512M (e.g. 16G)") }
-  await config.set("memory", normalized)
-  console.log(`memory = ${normalized}`)
+  await config.set(key as config.Key, normalized)
+  console.log(`${key} = ${normalized}`)
 }
diff --git a/src/vm.ts b/src/vm.ts
index 9f33af1..6e1728d 100644
--- a/src/vm.ts
+++ b/src/vm.ts
@@ -68,7 +68,7 @@ function hostMounts(home: string): { dev: boolean; code: boolean } {
 async function createContainer(home: string): Promise<void> {
   const mounts = hostMounts(home)
   let memory: string
-  try { memory = validateMemory((await getConfig("memory")) ?? DEFAULTS.memory) } catch { memory = DEFAULTS.memory }
+  try { memory = validateMemory((await getConfig("memory")) ?? DEFAULTS.memory) } catch (e) { info(`Invalid memory config, using default: ${e instanceof Error ? e.message : e}`); memory = DEFAULTS.memory }
   const args = ["container", "run", "-d", "--name", CONTAINER_NAME, "-m", memory]
   if (mounts.dev) args.push("--mount", `type=bind,source=${home}/dev,target=/host/dev,readonly`)
   if (mounts.code) args.push("--mount", `type=bind,source=${home}/code,target=/host/code,readonly`)