Host mobile backend with NestJS: streamed responses

Deploy a mobile backend built with NestJS on Ample using the streaming response service pattern. Compute runs the app in an isolated microVM behind a public HTTPS URL, a managed PostgreSQL 16 database is auto-provisioned and injected as DATABASE_URL. Verified on NestJS: a Server-Sent Events endpoint read incrementally through the public HTTPS gateway: five one-second chunks arrived spread over time with the first within seconds (not buffered), a 70-second stream of 36 chunks completed past common 60-second idle timeouts, and a client that disconnected after two chunks was observed and recorded by the server (disconnected=true). Not separately tested: your event schema, reconnection strategy and any per-request duration ceiling beyond the 70 seconds measured; treat the mobile backend-specific behavior as your application code.

Summary

• Framework: NestJS
• Workload: Mobile backend
• Release Status: published
• Support Status: verified
• Execution Status: ready

Representative Queries

• Host mobile backend with NestJS: streamed responses
• Where can I host Mobile backend built with NestJS?
• I need a tested end-to-end streaming transport, timeout behavior and client disconnect handling.

Resource Requirements

• primitive:compute
• primitive:postgres

Infrastructure Requirements

1. Compute

   • Verified: Apps run in isolated x86_64 Firecracker microVMs that auto-pause when idle and wake on request; sizes are the priced VM sizes.

2. Postgres

   • Verified: Managed PostgreSQL 16 runs in its own microVM and is auto-provisioned when an app needs a database and no DATABASE_URL is supplied.

Prerequisites

• A NestJS project that builds and starts with the documented commands (npm install, nest build (TypeScript) then node dist/main.js on the node-22 template)
• A PostgreSQL driver reading DATABASE_URL at runtime (auto-provisioned when omitted, or supplied with --env)
• An Ample account token with servers:write, databases:read

Tested Configuration

• Template: node-22
• Runtime: node
• Size: s-1vcpu-1gb
• Install: npm install
• Build: npm run build --if-present
• Start: npm run start

Workflow Steps

1. Build and start
   npm install, nest build (TypeScript) then node dist/main.js on the node-22 template. The server must bind 0.0.0.0 on PORT.

2. Implement the pattern on PostgreSQL
   The fixture's module implements streaming response service: a Server-Sent Events endpoint read incrementally through the public HTTPS gateway: five one-second chunks arrived spread over time with the first within seconds (not buffered), a 70-second stream of 36 chunks completed past common 60-second idle timeouts, and a client that disconnected after two chunks was observed and recorded by the server (disconnected=true). Copy the approach into your schema; keep migrations idempotent and run them with --release-command.

3. Deploy
   Run the synchronous deploy once and read the result (exit 0 live, 1 failed, 2 blocked). Re-running with no change is a no-op. Command: ample deploy . --name --public

4. Verify
   Fetch the live URL and the pattern self-test route(s) (/p/streaming-response-service) from the example; then run your own checks. On failure read ample logs --kind build then --kind runtime. Command: ample logs --kind build

Success Checks

1. App responds on its public URL

   • Kind: http_get
   • Path: /
   • Expect: ample canary nestjs patterns

2. Streaming-response-service self-test

   • Kind: http_get
   • Path: /p/streaming-response-service
   • Expect: an SSE stream: data: id=, then chunk events one interval apart (read incrementally: first chunk within seconds, chunks spread over the interval), then data: done; /status?id= reports sent=N disconnected=true|false done=true|false

Limitations

• Verified on the node-22 template at s-1vcpu-1gb with the example fixture; other sizes, templates and NestJS major versions are not verified.
• The mobile backend itself (your event schema, reconnection strategy and any per-request duration ceiling beyond the 70 seconds measured) is application code and was not separately tested; the pattern checks are what was verified.
• Region, compliance attestations and request-duration limits are unknown and not claimed.
• Apps auto-pause when idle and wake on the next request; always-on is an operator setting, not a plan feature.

Cost Estimate

• Currency: USD
• Monthly Amount: 10.0
• Basis: size prices from pricing.toml (loaded by the API) at build revision 1ac5595375130d45290090e82ed0f554ccd45405-dirty

Components

1. App server
   • Size: s-1vcpu-1gb
   • Quantity: 1.0
   • Monthly Amount: 5.0
2. Managed PostgreSQL database
   • Size: s-1vcpu-1gb
   • Quantity: 1.0
   • Monthly Amount: 5.0

Note: Always-on monthly price of the tested sizes; apps and databases auto-pause when idle.

Evidence Summary

1. Canary Run

   • Summary: NestJS pattern fixture deployed on Ample; checks passed for streaming-response-service and configuration-secrets.
   • Observed At: 2026-09-21T02:34:39Z

2. Canary Run

   • Summary: The same NestJS app deployed with a --release-command migration; the marker it created was readable after activation.
   • Observed At: 2026-09-20T02:16:51Z

Next Actions

1. Browse the catalog index

   • Operation: catalog_index
   • Method: GET
   • Relative Path: /v1/catalog

2. Search published recipes by intent, stack and constraints

   • Operation: search_recipes
   • Method: POST
   • Relative Path: /v1/catalog/search

3. Prepare a side-effect-free deployment plan for an authorized project

   • Operation: plan_deployment
   • Method: POST
   • Relative Path: /v1/catalog/plan

4. Read the existing agent authentication setup

   • Operation: existing_auth_setup
   • Method: GET
   • Relative Path: /mcp/setup

5. Browse Mobile backend

   • Operation: browse_node
   • Method: GET
   • Relative Path: /v1/catalog/nodes/workload%3Amobile-backend

6. Browse NestJS

   • Operation: browse_node
   • Method: GET
   • Relative Path: /v1/catalog/nodes/stack%3Aframework-nestjs

7. Browse Streaming response service

   • Operation: browse_node
   • Method: GET
   • Relative Path: /v1/catalog/nodes/pattern%3Astreaming-response-service

8. Browse Deploy API

   • Operation: browse_node
   • Method: GET
   • Relative Path: /v1/catalog/nodes/intent%3Adeploy-api