The SSH session froze, but the build kept running. Somewhere deep inside the VPC, inside a private subnet no one could reach, a process waited for a key it could never see.
Deploying a GPG proxy inside a VPC private subnet is not hard. Doing it right, so it scales, so it’s secure, and so it actually works with your CI/CD pipeline without leaking a single bit of trust? That’s where most deployments fail.
A GPG VPC private subnet proxy lets you sign, decrypt, and manage secrets inside isolated infrastructure. It means no internet exposure, no public IP, no awkward manual imports of long‑lived keys. The proxy sits inside your private subnet, reachable only from systems you control. Applications connect over secure internal channels. GPG operations happen in place. The keys never leave.
Why use a GPG proxy in a VPC private subnet
Isolation is the first reason, and the only one that matters if your threat model is strict. No route tables pointing to the internet. No NAT gateway for the proxy host. The instance holds your GPG key in memory or on disk with hardened permissions. The private network limits the blast radius of any compromise.
Performance is the second. Internal traffic within a VPC is fast and predictable. Latency drops when signing or decrypting large payloads for binary distributions, container images, or configuration bundles.
How to structure your deployment
- Provision the private subnet with no direct internet route. Set up security groups to allow only required inbound connections from known application hosts.
- Deploy the proxy host with minimal OS footprint, hardened SSH, and GPG installed from a trusted source.
- Import or generate keys directly within the host. Store them with GPG’s keyring in a directory owned by a dedicated user.
- Expose a local service (like a simple TCP socket or HTTP API bound to internal IPs) that accepts sign/decrypt requests from your applications.
- Lock down IAM or role access if using a cloud provider. The compute instance should have the least privilege possible.
Security considerations
Public key sharing is safe, but private keys are not. Never copy them out. Never mount them on an EFS or other shared volume without encryption. Monitor all process calls to GPG with your logging pipeline. Keep the proxy patched and rotate keys on schedule.
Integrating into CI/CD
Build systems inside the same VPC can call the proxy service during build or release jobs. Instead of storing GPG keys in your CI secrets store or environment variables, you hand off payloads internally for signing. This design removes exposure from developer workstations and build logs.
Scaling the proxy
If traffic grows, run multiple proxies behind an internal load balancer. Each proxy has the same locked‑down key set. Use private DNS for service discovery. Maintain strict update policies for key material and GPG configuration.
You can have this running in minutes. No custom glue code, no costly infrastructure planning phase, no weeks lost to security reviews. See it live at hoop.dev and watch your GPG VPC private subnet proxy deployment go from idea to reality before your coffee cools.