---
title: "Session: vpc-and-nat-gateways — 2026-08-13"
type: source
tags: [zcode, session-transcript, demo]
date: 2026-08-13
source_file: raw/sessions/infra-stack/2026-08-13-vpc-and-nat-gateways.md
sessionId: demo-892373135182
slug: vpc-and-nat-gateways
project: infra-stack
started: 2026-08-13T15:00:00+00:00
ended: 2026-08-13T16:00:00+00:00
cwd: /home/dev/code/infra-stack
gitBranch: feat/vpc
permissionMode: default
model: glm-4.6
user_messages: 1
tool_calls: 2
tools_used: [Bash, Edit]
tool_counts: {"Edit": 1, "Bash": 1}
token_totals: {"input": 6000, "cache_creation": 12000, "cache_read": 36000, "output": 2000}
turn_count: 1
hour_buckets: {"2026-08-13T15": 4}
duration_seconds: 3600
is_subagent: false
---

# Session: vpc-and-nat-gateways — 2026-08-13

**Project:** `infra-stack` · **Branch:** `feat/vpc` · **Mode:** `default` · **Model:** `glm-4.6`

## Summary

Added the VPC module the EKS cluster sits in: three AZs, private and public subnets, one NAT gateway per AZ in prod and a single shared one in staging to save cost.

## Conversation

### Turn 1 — User

Staging is burning money on NAT gateways.

### Turn 1 — Assistant

Make the NAT layout a variable: one per AZ for prod, a single shared gateway for staging.

**Tools used in this turn:**

- `Edit`: modules/vpc/main.tf
- `Bash`: terraform plan -var-file=staging.tfvars — 2 to destroy

## Connections

- [[infra-stack]]
- [[Terraform]]
- [[AWSVPC]]