altS3.com Developer Docs

Endpoints

altS3.com exposes a managed S3-compatible endpoint. It expects path-style requests unless you control DNS + certificates for virtual hosts.

• Example REST endpoint: https://s3.us.alts3.com
• Example region string: us-east-1 (platform default)
• Path-style addressing: set aws configure set s3.use_path_style true or forcePathStyle: true in SDKs.

Confirm your assigned endpoint and region inside the dashboard or welcome email before wiring up clients.

Advanced S3 feature parity

altS3 matches the same capabilities you rely on in self-hosted S3-compatible stacks:

• Erasure-coded durability + bitrot protection on every bucket.
• Bucket versioning & object locking for governance/compliance workloads.
• Server-side encryption (SSE-S3/AES-256 or SSE-C) on uploads.
• Lifecycle policies that expire or transition objects based on prefixes/tags.
• Per-tenant quotas + telemetry surfaced in the altS3 portal.
• Open-source mc CLI compatibility for scripting and automation.

Bring your existing automation, mc command sets, and SDK behaviors—they work the same way against altS3.

Authentication

We accept S3-style signatures (v4). Provide your access key and secret key in the client/SDK.

# example ~/.aws/credentials
[alts3]
aws_access_key_id = ALTS3ACCESSKEY
aws_secret_access_key = alts3-secret-key

# example ~/.aws/config
[profile alts3]
region = YOUR_ALTS3_REGION   # typically us-east-1 for altS3
output = json
s3 =
  addressing_style = path

Time skew can cause signature errors. Ensure your server time is accurate.

Buckets

Buckets behave like standard S3 buckets:

• Create: PUT /{bucket}
• List: GET /
• Delete: DELETE /{bucket}

aws s3 mb s3://my-bucket \
  --endpoint-url https://s3.us.alts3.com \
  --region YOUR_ALTS3_REGION \
  --profile alts3

Our platform enforces JSON bucket policies (similar to AWS bucket policies). Classic ACLs are not supported—grant access via policies or dedicated access keys.

---

Versioning & object locking

Full S3 versioning and WORM-style object locking are available—enable versioning per bucket, then optionally require retention windows.

# enable versioning
aws s3api put-bucket-versioning \
  --bucket my-bucket \
  --versioning-configuration Status=Enabled \
  --endpoint-url https://s3.us.alts3.com \
  --region YOUR_ALTS3_REGION \
  --profile alts3

# optional: enable governance-mode object lock with default retention
aws s3api put-object-lock-configuration \
  --bucket my-bucket \
  --object-lock-configuration '{
    "ObjectLockEnabled":"Enabled",
    "Rule":{"DefaultRetention":{"Mode":"GOVERNANCE","Days":30}}
  }' \
  --endpoint-url https://s3.us.alts3.com \
  --region YOUR_ALTS3_REGION \
  --profile alts3

Retention settings require versioning to be enabled first. Governance mode lets admins bypass locks with the appropriate header; Compliance mode is immutable until expiration.

Objects

Upload, download, list, and delete work like S3. Multipart uploads are supported.

# upload
aws s3 cp ./file.zip s3://my-bucket/file.zip \
  --endpoint-url https://s3.us.alts3.com \
  --region YOUR_ALTS3_REGION \
  --profile alts3

# download
aws s3 cp s3://my-bucket/file.zip ./ \
  --endpoint-url https://s3.us.alts3.com \
  --region YOUR_ALTS3_REGION \
  --profile alts3

For very large objects, use multipart. Most SDKs handle this automatically.

Lifecycle policies

Use lifecycle rules to expire or transition prefixes/tags—perfect for keeping buckets tidy without manual cleanup.

cat > lifecycle.json <<'EOF'
{
  "Rules": [
    {
      "ID": "logs-expire",
      "Status": "Enabled",
      "Prefix": "logs/",
      "Expiration": { "Days": 30 }
    },
    {
      "ID": "tmp-cleanup",
      "Filter": { "Tag": { "Key": "ttl", "Value": "7d" } },
      "Status": "Enabled",
      "Expiration": { "Days": 7 }
    }
  ]
}
EOF

aws s3api put-bucket-lifecycle-configuration \
  --bucket my-bucket \
  --lifecycle-configuration file://lifecycle.json \
  --endpoint-url https://s3.us.alts3.com \
  --region YOUR_ALTS3_REGION \
  --profile alts3

Lifecycle rules run natively on altS3. Use prefixes, filters, and tags to dial in the exact clean-up behavior you want.

Server-side encryption

altS3 honors standard SSE-S3 (AES256) and SSE-C headers, so objects are encrypted at rest by default. Use the AWS CLI/S3 APIs to enforce encryption per upload.

# SSE-S3 (managed keys)
aws s3 cp ./finance.csv s3://my-bucket/finance.csv \
  --sse AES256 \
  --endpoint-url https://s3.us.alts3.com \
  --region YOUR_ALTS3_REGION \
  --profile alts3

# SSE-C (customer-provided key)
aws s3 cp ./secret.tgz s3://my-bucket/secret.tgz \
  --sse-c AES256 \
  --sse-c-key "$(openssl rand -base64 32)" \
  --endpoint-url https://s3.us.alts3.com \
  --region YOUR_ALTS3_REGION \
  --profile alts3

For SSE-C workloads, store the keys securely—altS3 never retains a copy. SSE-S3 uploads automatically inherit the platform’s KMS integration.

Presigned URLs

Generate a temporary URL for PUT or GET using your client. This is handy for browsers and apps.

# presigned GET
aws s3 presign s3://my-bucket/file.zip \
  --endpoint-url https://s3.us.alts3.com \
  --region YOUR_ALTS3_REGION \
  --profile alts3 \
  --expires-in 3600

Presigned URLs are time-limited; use shorter expirations for public sharing.

SDK examples

Python (boto3)

import boto3

session = boto3.session.Session()
s3 = session.client(
    service_name="s3",
    region_name="YOUR_ALTS3_REGION",
    endpoint_url="https://s3.us.alts3.com",
    aws_access_key_id="ALTS3ACCESSKEY",
    aws_secret_access_key="alts3-secret-key",
)

# list buckets
print(s3.list_buckets())

Node.js (AWS SDK v3)

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

const client = new S3Client({
  region: "YOUR_ALTS3_REGION",
  endpoint: "https://s3.us.alts3.com",
  forcePathStyle: true,
  credentials: {
    accessKeyId: "ALTS3ACCESSKEY",
    secretAccessKey: "alts3-secret-key",
  },
});

const data = await client.send(new ListBucketsCommand({}));
console.log(data.Buckets);

Note forcePathStyle: true is often required when using S3-compatible providers.

mc CLI quickstart

The open-source mc CLI works unchanged against altS3, so you can keep your existing scripting, lifecycle management, and replication routines.

# configure an alias
mc alias set alts3 https://s3.us.alts3.com ALTS3ACCESSKEY alts3-secret-key

# inspect buckets
mc ls alts3

# mirror a folder
mc mirror ./assets alts3/my-bucket/assets

# manage policies/quotas
mc admin policy list alts3

Use the same mc commands you already run against self-hosted S3-compatible clusters—no changes needed.

Features not available

To deliver $5.95/TB on the base tier we disable some advanced S3 capabilities:

• No Object Lambda
• No S3 Inventory reports
• No S3 Batch Operations
• No Glacier-like archival tiers
• No bucket ACLs or S3 Access Points (use bucket policies instead)
• No AWS event notifications/Lambda triggers

If your workload uses any of the above, keep it on Amazon S3 or another provider. For backups, media, app assets, and logs, altS3.com is drop-in.

Troubleshooting

SignatureDoesNotMatch

• Check endpoint is exactly https://s3.us.alts3.com
• Check region matches YOUR_ALTS3_REGION (defaults to us-east-1 if unspecified)
• Check system time (NTP)

AccessDenied

• Bucket does not exist or is owned by another account
• Your access key was rotated; request a new one