Connect to NEX - Polymarket Documentation

After approval, use either connection below. For the best latency results, use PrivateLink in NEX’s AWS London zone.

Set Up Your Connection

AWS PrivateLink
Public IP Allowlisting

Create an Endpoint

We’ll allowlist your 12-digit AWS account ID and send the service name. Create an IPv4 Interface VPC endpoint in eu-west-2, AZ ID euw2-az1 only. Allow TCP 443 from your clients in its security group and disable Private DNS (private_dns_enabled = false). Check the AZ ID: names such as eu-west-2a vary across accounts. Another AZ will not provide failover.

Get the Connection Approved

Send us the endpoint ID (vpce-…). Wait for approval and status available.

Set Up DNS

In a private hosted zone attached to your VPC, point these CNAMEs to your endpoint DNS name:

nex.preprod.defi.euw2.polymarket.sh
nex-ws.preprod.defi.euw2.polymarket.sh

Preserve the service hostname in TLS SNI and the HTTP Host header if connecting through endpoint DNS directly.

Check Connectivity

Run from a client inside your connected VPC after setting up DNS:

curl -i https://nex.preprod.defi.euw2.polymarket.sh/health

Expect HTTP 200.

AWS bills endpoint usage to your account.

Send Your Outbound IPs

Send each stable public IPv4 address your clients use, individually (/32). For clients behind NAT, use the NAT gateway’s public addresses. Wait for our approval before connecting.

Map the Service Hostnames

Map the trading and WebSocket hostnames to 51.24.102.79 in your resolver or hosts file. Their default DNS does not select the public connection. Allow outbound TCP 443 and keep the hostname in TLS SNI and HTTP Host.

Check Connectivity

Run from an allowlisted client. This selects the public address while preserving the hostname for TLS and routing:

curl -i \
  --connect-to nex.preprod.defi.euw2.polymarket.sh:443:51.24.102.79:443 \
  https://nex.preprod.defi.euw2.polymarket.sh/health

Expect HTTP 200.

Service Addresses

Service	Base URL
Trading API	`https://nex.preprod.defi.euw2.polymarket.sh`
WebSocket feeds	`wss://nex-ws.preprod.defi.euw2.polymarket.sh`
Markets (Gamma)	`https://gamma-api-preprod.polymarket.dev`
Relayer	`https://relayer-preprod.polymarket.dev`

Gamma and the relayer require x-client-id and x-client-secret headers. We’ll send the credentials privately after approval. These are separate from your trading credentials.