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Data warehouse ⇄ Database

AWS S3 to Azure Cosmos DB integration — real-time, two-way sync

Keep AWS S3 and Azure Cosmos DB in sync without custom scripts. Cut weeks of integration work, eliminate silent data drift, and give your team a single, reliable source of truth.

  • SOC 2 and 6 other compliance frameworks
  • POC with real engineers in minutes

Adopted by fast-scaling companies moving mission-critical data in real time

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Why teams connect AWS S3 and Azure Cosmos DB

Connect Azure Cosmos DB and AWS S3 with one live, two-way sync: operational rows flow into the warehouse, and computed results flow back where systems can read them fast.

Operational databases and analytical warehouses want the same data at different moments. Analysts want Azure Cosmos DB's rows in AWS S3, current and joinable, without a change-data-capture pipeline to maintain. Engineers want the outputs of warehouse work, such as aggregates, features, and segments, available in Azure Cosmos DB where the services that read from it get them at normal query latency.

Stacksync covers both directions with one connection. Tables or collections in Azure Cosmos DB sync into AWS S3 in real time, and result tables in AWS S3 sync back into Azure Cosmos DB, with schema and type mapping between the two systems handled for you.

Common use cases

  • Archive change history from ongoing syncs as timestamped files for audit and replay.
  • Ingest partner or vendor file drops (CSV, JSON, Parquet) from a bucket into a database or CRM as records.
  • Consolidate documents from multiple containers into a single reporting store.
  • Stream operational documents from Cosmos DB into a SQL warehouse via the change feed for analytics without hitting request-unit budgets with full scans.

Fresh analytics without loading windows

Because changes stream continuously, analysts query current data instead of waiting for last night's load.

Offload heavy reads

Point analytical queries at the synced copy in AWS S3 and keep Azure Cosmos DB focused on its operational workload.

Operational data in the warehouse, minus the pipeline

Rows from Azure Cosmos DB land in AWS S3 as they change, replacing hand-built CDC and batch extract jobs.

What you can sync between AWS S3 and Azure Cosmos DB

Representative objects on each side — any object or custom field can map to any target. Schemas are auto-detected; types are converted between the two systems.

AWS S3 objects Azure Cosmos DB objects
Multipart Uploads The mechanism used to write large export files reliably. Partition keys Determine data distribution and must be included on writes for the sync to route items correctly.
Buckets Top-level containers a sync targets; region and policy are set at this level. Change feed entries Ordered record of inserts and updates per partition, consumed for incremental sync.
Objects The stored files (CSV, JSON, Parquet); syncs read them as datasets or write exports into them. Stored procedures and triggers Server-side logic scoped to a partition; relevant when writes must respect existing validation.
Prefixes Key-name paths used to partition synced datasets, since S3 has no real directories. Databases Top-level namespaces that scope containers and throughput provisioning.
Object Metadata System and user-defined metadata read alongside object contents. Containers The unit of partitioning and throughput; each container maps to a synced collection.
Object Versions Prior copies retained when versioning is enabled, relevant for reprocessing. Items (JSON documents) Schema-flexible JSON records read and written during sync; nested structures are flattened or mapped as needed.
What ships with AWS S3 ⇄ Azure Cosmos DB

Connect AWS S3 and Azure Cosmos DB for flexible, real-time data sync.

Real-time sync, workflow automation, event queues, EDI, and monitoring, for every AWS S3–Azure Cosmos DB connection.

Real-time

Two-way sync

Changes in AWS S3 or Azure Cosmos DB instantly reflect in both systems. No stale data, no manual imports.

No-code + pro-code

Workflow automation

Trigger automated workflows whenever AWS S3 or Azure Cosmos DB data changes, update records, fire webhooks, or kick off sequences without brittle API scripts.

At scale

Event queues

Handle millions of events per minute without losing a single AWS S3 or Azure Cosmos DB record.

Observability

Monitoring

Track your AWS S3 ⇄ Azure Cosmos DB sync health, view errors, and replay failed events in one click.

Trading partners

EDI

Transform legacy EDI complexity into simple database interactions between AWS S3 and Azure Cosmos DB.

How the AWS S3 and Azure Cosmos DB connectors work

AWS S3

Integration surface
REST API (the S3 API), accessed directly or through AWS SDKs
Authentication
AWS IAM credentials with SigV4 signing; commonly a role scoped to specific buckets and prefixes
Change detection
S3 Event Notifications on object create/delete delivered to SQS, SNS, Lambda, or EventBridge; list-based polling as a fallback
Capabilities
read · write · webhooks
Rate limits
Request throughput scales per prefix; sustained high-volume workloads should spread keys across prefixes

Azure Cosmos DB

Integration surface
REST API and SDKs over HTTPS (API for NoSQL, formerly the SQL API); also MongoDB, Cassandra, Gremlin, and Table API surfaces
Authentication
Account keys, resource tokens, or Microsoft Entra ID role-based access
Change detection
Built-in change feed exposing inserts and updates in order within each partition key range
Capabilities
read · write · CDC
How it works

How to connect AWS S3 to Azure Cosmos DB — three steps, no code

Configure and sync within minutes, no code. Whether you sync 50k or 100M+ records, Stacksync handles the queues, infra, and plumbing. Integrations are non-invasive and need zero setup on your systems.

  1. 01

    Connect your apps

    Authenticate AWS S3 and Azure Cosmos DB with each platform's native method — OAuth, API keys, or service accounts — plus secure options like SSH tunneling, IP whitelisting, and VPC peering.

    • OAuth 2.0
    • SSH tunnel
    • VPC peering
    AWS S3 connected
    Azure Cosmos DB connected
    OAuth 2.0
    SSH tunnel
    SSL certificate
    VPC peering
  2. 02

    Choose tables

    Pick the AWS S3 and Azure Cosmos DB objects to sync — Stacksync auto-detects both schemas, including custom fields where the platform exposes them. Sync to existing tables, or let Stacksync create new ones with ideal data types.

    • Standard objects
    • Custom objects
    • Auto-schema
    objects · AWS S3 ⇄ Azure Cosmos DB
    Customers 12,480
    Sales Orders 8,213
    Invoices 5,902
    Items 1,344
  3. 03

    Map fields

    Fields map automatically even when names and types differ. Stacksync handles transformation and type casting for you, zero configuration required.

    • Auto-map
    • Type casting
    • Transforms
    AWS S3 Azure Cosmos DB
    Company company_name text
    Email email text
    Amount amount numeric
    Created created_at timestamp
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FAQ

AWS S3 and Azure Cosmos DB integration FAQ

SECURITY

Security teams love Stacksync

As a data company, we understand the importance of keeping your data secure. Stacksync is built with security best practices to keep your data safe at every layer, and is DPF-certified for US, EU, UK and CH data transfers.

Learn more about security
SOC 2 type II
ISO 27001
HIPAA BAA
GDPR
CCPA
CSA STAR
DPF US-EU-UK-CH
→ SECURITY WITH BENEFITS

SSO & SCIM

Let your users access Stacksync from your centralized user management systems. Works with Okta, Azure, Google SSO and more.

Alerts

Immediately get alerted about record syncing issues over email, Slack, PagerDuty and WhatsApp. Resolve issues from a centralized dashboard with retry and revert options.

Secure connection options

Securely connects to your systems with:

OAuth 2 SSH Tunnelling SSL certificates IP Whitelisting VPN gateway VPC peering and more

Related integrations

Every pair below is a real-time, two-way sync. Search all 386 integrations available for AWS S3 and Azure Cosmos DB.

Popular · 8 of 386
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