Storage / Buckets — MIOSA Docs

What you get

Per project: an S3-compatible bucket, accessed through MIOSA endpoints. Credentials injected as env vars:


STORAGE_BUCKET=miosa-proj_xxx-uploads
STORAGE_ENDPOINT=https://storage.miosa.app
STORAGE_KEY_ID=...
STORAGE_KEY_SECRET=...

Your code uses the standard S3 client libraries:

import { S3Client, PutObjectCommand } from "@aws-sdk/client-s3"

const s3 = new S3Client({
  endpoint: process.env.STORAGE_ENDPOINT,
  credentials: {
    accessKeyId: process.env.STORAGE_KEY_ID!,
    secretAccessKey: process.env.STORAGE_KEY_SECRET!,
  },
  region: "us-east-1",
})

await s3.send(new PutObjectCommand({
  Bucket: process.env.STORAGE_BUCKET,
  Key: "uploads/foo.png",
  Body: pngBuffer,
}))

Signed URLs for browser uploads

Don’t proxy file uploads through your runtime. Mint a signed URL server-side; the browser uploads directly to storage:

// Server
const url = await miosa.storage.signedUrl({
  bucket: process.env.STORAGE_BUCKET!,
  key: `users/${userId}/avatar.png`,
  operation: "put",
  expiresInSec: 300,
  contentType: "image/png",
})
return { uploadUrl: url }

// Browser
await fetch(uploadUrl, {
  method: "PUT",
  body: file,
  headers: { "Content-Type": "image/png" },
})

Same pattern for downloads (operation: "get"). Signed URLs are scoped (single key, single operation, short expiry) — no risk of leaking bucket-wide credentials to a browser.

Each object can be private (default; access only via signed URL) or public (served from a *.storage.miosa.app URL). Public objects can also be fronted by a custom domain via your project’s Domain settings.

Bandwidth and storage costs

Two billable dimensions:

Storage — GB-month for stored bytes.
Egress — GB out from MIOSA to the public internet. Storage-to-runtime within MIOSA is free.

Attribution is carried on every event for chargeback.

Limits

Limit	Default	Tunable
Storage per project	1 GB	Yes (plan-dependent)
Max object size	5 GB	Up to 100 GB for multipart
List keys per call	1000	Standard S3 pagination

Sandboxes can use the bucket too

The same env vars are injected into sandboxes for dev / testing. Upload from inside a sandbox:

await sandbox.exec({
  cmd: "aws",
  args: ["s3", "cp", "/workspace/build.tar.gz", `s3://${process.env.STORAGE_BUCKET}/builds/`],
  env: {
    AWS_ACCESS_KEY_ID: process.env.STORAGE_KEY_ID,
    AWS_SECRET_ACCESS_KEY: process.env.STORAGE_KEY_SECRET,
    AWS_ENDPOINT_URL: process.env.STORAGE_ENDPOINT,
  },
})

Bring your own bucket?

Yes. Set the env vars to point at an external S3-compatible bucket (real AWS, Backblaze B2, R2, etc.). MIOSA injects whatever you set.