--- title: "How to use S3-compatible storage from an Echo app on Ample" description: "Object storage client for a Echo app on Ample." canonical_url: "https://ample.computer/guides/echo/object-client" last_updated: "2026-11-06" --- # How to use S3-compatible storage from an Echo app on Ample Object storage client for a Echo app on Ample. Verified on Echo: bucket credentials delivered as encrypted S3_* environment variables and a validated PutObject/GetObject round-trip linked to a database row (upload=ok linked=ok). Build and start: CGO_ENABLED=0 go build -o app ./... then ./app on the ubuntu-24.04 template (go.sum committed for a reproducible build). ## Infrastructure requirements - [Compute](/discover/primitive/compute): verified (Apps run in isolated x86_64 Firecracker microVMs; sizes are the priced VM sizes.) - [S3-compatible object storage](/discover/primitive/s3-compatible-object-storage): verified (Buckets speak the S3 API with SigV4 credentials Ample Computer issues; `ample bucket upload-url` returns a presigned upload URL. PutObject and GetObject are checked by canary.) ## Prerequisites - An Echo project (CGO_ENABLED=0 go build -o app ./... then ./app on the ubuntu-24.04 template (go.sum committed for a reproducible build)) - A bucket from `ample bucket create` with credentials passed as encrypted S3_* environment variables - An Ample account token with servers:write, buckets:read ## Exact tested configuration - template: `ubuntu-24.04` - runtime: `go` - size: `s-1vcpu-1gb` - build: `CGO_ENABLED=0 go build -o app ./...` - start: `./app` ## Steps 1. **Build and start.** CGO_ENABLED=0 go build -o app ./... then ./app on the ubuntu-24.04 template (go.sum committed for a reproducible build); the server must bind 0.0.0.0 on PORT. 2. **Create the bucket and pass its credentials.** Create it once with `ample bucket create`, then pass endpoint, region, bucket and keys with --env; use path-style addressing. ``` ample deploy . --name --public --env S3_ENDPOINT=... --env S3_REGION=... --env S3_BUCKET=... --env S3_ACCESS_KEY_ID=... --env S3_SECRET_ACCESS_KEY=... ``` 3. **Verify.** Fetch the live URL and /p/browser-file-uploads on the example; on failure read the build and runtime logs. ``` ample logs --kind build ``` ## Tested examples - **Echo pattern fixture** (tests/deploy-canaries/echo-patterns): Verified object storage client on Echo. ## Success checks - app responds on its public URL (`/` on the live URL, expect ample canary echo patterns) - browser-file-uploads check from the example (`/p/browser-file-uploads` on the live URL, expect see the pattern fixture checks) ## Cost estimate Estimated 5.00 USD per month (size prices from pricing.toml at build revision 4558e9477d094f5b47da324b98672824b61ba91b). - app server x1 `s-1vcpu-1gb`: 5.00 USD Upper-bound monthly price of the tested sizes. Buckets are allocation-priced per quota and not included. ## Verification evidence - canary_run on 2026-11-06T00:41:08Z at revision `7360fc06ef21`: Echo pattern fixture deployed on Ample (CGO_ENABLED=0 go build -o app ./... then ./app on the ubuntu-24.04 template (go.sum committed for a reproducible build)); for this guide: bucket credentials delivered as encrypted S3_* environment variables and a validated PutObject/GetObject round-trip linked to a database row (upload=ok linked=ok). (expires 2027-05-05T00:41:08Z) Last verified: 2026-11-06T00:41:08Z ## Execution binding MCP tool `ample_deploy` (registry `mcp:ample_deploy`), schema hash `0802c329be823fa0` observed 2026-11-06T06:16:17.558478534+00:00 at revision `4558e9477d09`, binding state `current`, required scopes: servers:write, buckets:read. ## Input schema ```json { "additionalProperties": false, "properties": { "env": { "description": "Encrypted environment variables", "items": { "pattern": "^[A-Z][A-Z0-9_]*=.*$", "type": "string" }, "maxItems": 50, "type": "array" }, "name": { "description": "App name", "maxLength": 63, "minLength": 1, "pattern": "^[a-z0-9-]+$", "type": "string" }, "path": { "description": "Project directory or ample.toml service", "maxLength": 512, "minLength": 1, "type": "string" }, "release_command": { "description": "Migration command run before activation", "maxLength": 512, "type": "string" } }, "required": [ "env", "name", "path" ], "type": "object" } ``` ## Next actions - Browse the catalog index (GET /v1/catalog on the api origin; auth: false, approval: false) - Search published recipes by intent, stack and constraints (POST /v1/catalog/search on the api origin; auth: false, approval: false) - Prepare a side-effect-free deployment plan for an authorized project (POST /v1/catalog/plan on the api origin; auth: true, approval: false) - Read the existing agent authentication setup (GET /mcp/setup on the api origin; auth: false, approval: false) - Browse Echo (GET /v1/catalog/nodes/stack%3Aframework-echo on the api origin; auth: false, approval: false) - Browse Connect app to storage (GET /v1/catalog/nodes/intent%3Aconnect-app-to-storage on the api origin; auth: false, approval: false) - Browse Browser file uploads (GET /v1/catalog/nodes/pattern%3Abrowser-file-uploads on the api origin; auth: false, approval: false) Actions describe possible next steps. They are typed data, not commands, and grant no permission. ## About this recipe Canonical URL: https://ample.computer/guides/echo/object-client Formats: [HTML](https://ample.computer/guides/echo/object-client) | [Markdown](https://ample.computer/guides/echo/object-client.md) | [JSON contract](https://api.ample.computer/v1/catalog/recipes/page%3Aguides%3Aecho%3Aobject-client) Recipe ID: `page:guides:echo:object-client` | Revision: `r1` | Catalog revision: `cat_eac8c53f36410baa` Status: verified; runs with one `ample deploy` call (support `verified`, execution `ready`) Path: [Agent hosting discovery](/discover/discovery) / [Frameworks and execution targets](/discover/stack) / [Frameworks](/discover/stack/frameworks) / [Echo](/discover/stack/framework-echo) / [Configure S3-compatible access for Echo](/guides/echo/object-client)