Vera AWS

Local AWS EC2 emulator. Version 0.1 : 89 resource types — VPCs, instances, security groups, volumes, and more (complete list at the end) — running on your machine with no AWS account needed.

Check out the Vera website for more information.

Setup

./install.sh

This creates a venv, installs dependencies, sets up dummy AWS credentials (~/.aws/credentials), and generates two wrapper scripts in .bin/:

• awscli — drop-in for aws, routes requests to the emulator
• terlocal — drop-in for terraform, configures the AWS provider endpoint

Prerequisites

• Python 3.10+
• AWS CLI and Terraform are installed automatically by install.sh if missing (macOS/Linux)

Usage

Start the emulator on one terminal:

uv run main.py
# Running at http://localhost:5003

AWS CLI via uv run awscli

uv run awscli ec2 create-vpc --cidr-block 10.0.0.0/16
# {
#     "Vpc": {
#         "VpcId": "vpc-28bc3a23",
#         "CidrBlock": "10.0.0.0/16",
#         "State": "available",
#         ...
#     }
# }

AWS CLI directly via awscli

Simply activate the venv and run awscli:

source .venv/bin/activate

awscli ec2 describe-vpcs
awscli ec2 run-instances --image-id ami-12345678 --instance-type t2.micro
awscli ec2 describe-instances

Terraform

Write standard Terraform — no provider overrides needed:

provider "aws" {
  region = "us-east-1"
}

resource "aws_vpc" "main" {
  cidr_block = "10.0.0.0/16"
}

Then use uv run terlocal instead of terraform. Or simply activate the venv and directly run terlocal:

source .venv/bin/activate

terlocal init
terlocal apply -auto-approve
terlocal destroy -auto-approve

See tests/tf/ for more examples.

Running Tests

# Terminal 1 — start the emulator
uv run main.py

# Terminal 2 — run 260 CLI commands against it
cd tests
uv run eval_emulator.py test.sh --endpoint http://localhost:5003 \
  --checkpoint eval_results.json --start-from 0
uv run analyze_results.py eval_results.json

# Terraform smoke test
cd tests/tf/00-simple-vpc
uv run terlocal init && uv run terlocal apply -auto-approve

Emulator	Passing (260 commands)
LocalStack	122 (47%)
Vera AWS	187 (72%)

Project Structure

main.py                        Flask server (port 5003)
install.sh                     Sets up awscli/terlocal wrappers
emulator_core/
├── state.py                   In-memory resource store
├── backend.py                 Base backend class
├── gateway/base.py            Action → backend dispatch
└── services/                  89 resource modules
tests/
├── test.sh                    260 CLI commands (awscli wrapper)
├── eval_emulator.py           Evaluator with checkpointing
└── tf/                        Terraform test cases

Supported Resources

Vera AWS supports the following resources (via EC2 API):

• Account Attributes
• AFIs
• AMIs
• Authorization Rules
• AWS Marketplace
• Block Public Access
• Bundle Tasks
• BYOASN
• BYOIP
• Capacity Reservations
• Carrier Gateways
• Certificate Revocation Lists
• Client Connections
• Client VPN Endpoints
• Configuration Files
• Customer Gateways
• Customer Owned IP Addresses
• Declarative Policies (Account Status Report)
• Dedicated Hosts
• DHCP Options
• EC2 Fleet
• EC2 Instance Connect Endpoints
• EC2 Topology
• Elastic Graphics
• Elastic IP Addresses
• Elastic Network Interfaces
• Encryption
• Event Notifications
• Event Windows For Scheduled Events
• Fast Snapshot Restores
• Infrastructure Performance
• Instance Types
• Instances
• Internet Gateways
• IPAMs
• Key Pairs
• Launch Templates
• Link Aggregation Groups
• Local Gateways
• Managed Prefix Lists
• NAT Gateways
• Network Access Analyzer
• Network ACLs
• Nitro TPM
• Placement Groups
• Pools
• Reachability Analyzer
• Regions And Zones
• Reserved Instances
• Resource Discoveries
• Resource IDs
• Route Servers
• Route Tables
• Routes
• Scheduled Instances
• Scopes
• Security Groups
• Serial Console
• Service Links
• Snapshots
• Spot Fleet
• Spot Instances
• Subnets
• Tags
• Target Networks
• Traffic Mirroring
• Transit Gateway Connect
• Transit Gateway Multicast
• Transit Gateway Peering Attachments
• Transit Gateway Policy Tables
• Transit Gateway Route Tables
• Transit Gateways
• Verified Access Endpoints
• Verified Access Groups
• Verified Access Instances
• Verified Access Logs
• Verified Access Trust Providers
• Virtual Private Gateway Routes
• Virtual Private Gateways
• VM Export
• VM Import
• Volumes
• VPC Endpoint Services
• VPC Endpoints
• VPC Flow Logs
• VPC Peering
• VPCs
• VPN Concentrators
• VPN Connections