AppService construct wires the per-env EC2 box and its internet path. The
seahaven-vpc and the internet-facing seahaven-com ALB are SHARED with the
on-prem seahaven-site stack, so everything VPC/ALB/zone-side is IMPORTED and
never owned/mutated; open-swe only ADDS its own resources.
Per env (open-swe-stack.ts → AppService):
- ARM64 EC2 box (t4g.medium dev / t4g.large prod) in private1 (us-east-1a,
in-AZ NAT egress). requireImdsv2, gp3-encrypted root, deleteOnTermination
(no RETAIN volume — replacement-tolerant; see ami-cache.ts).
userDataCausesReplacement; user-data rendered from deploy/ami/user-data.sh.
- Standalone instance SG: ingress ONLY from the shared ALB SG on :80; egress
via NAT. The ALB SG is opened to the box via a STANDALONE CfnSecurityGroupEgress
(the imported, on-prem-owned SG is never mutated).
- Target group → instance:80 (nginx is sole ingress; LangGraph :2024 stays
loopback). Health check GET /healthz.
- Two rules on the imported :443 listener, both → the TG:
* webhooks (priority 2 dev / 3 prod): host∈{openswe,hooks}-<env> AND /webhooks/*
* site (priority 10 dev / 11 prod): host=openswe-<env> (dashboard SPA + api)
Webhooks MUST sit below the on-prem host-agnostic /webhooks/* rule (priority 5)
or it would steal every webhook — first-match-by-ascending-priority.
- Route53 alias records (openswe[-dev] + hooks[-dev]) → shared ALB.
- 4 CloudWatch log groups at 30-day retention (IaC-owned; mirrors CW-agent config).
Security (/sh-security-review T12): iac-iam pass clean. Logic pass → 1 confirmed
medium fixed (OSWE-T12-01: nginx 1MB default client_max_body_size would 413 large
GitHub webhooks pre-signature-verification → set 25m on /webhooks/, 10m on
/dashboard/api/); hooks host scoped to /webhooks/* only (OSWE-T12-02 hygiene);
XFF-spoof candidate killed (no code trusts leftmost XFF). No confirmed
critical/high.
Synth-only; not deployed. AMI is the cdk.context.json placeholder until the baked
open-swe-base-arm64 id is pinned pre-deploy. tsc/synth(dev+prod)/jest(16) clean.
Next: T13 GPT-4.1 cross-review of the SG/listener diff before any deploy.
PR#2 of the AWS migration. deploy/ami/: Packer template (Ubuntu 24.04 arm64,
uv+py3.12, nginx, awscli v2, CW agent; no swapfile), provisioning-only user-data
(userDataCausesReplacement rationale), systemd unit + nginx + CW templates.
Incorporates T5 /sh-security-review fixes: langgraph binds 127.0.0.1 (not 0.0.0.0);
nginx is the sole ingress proxying only /dashboard/api/ + /webhooks/; ExecStartPre
runs fetch-config as root (+) and passes the env arg; the app runs as the
unprivileged openswe user reading an openswe-owned 0600 .env. packer validate clean.
