Airbyte VS Debezium + Kafka

Airbyte was founded in 2020 as an open-source data integration company, and launched its cloud service in 2022.

Airbyte started as a Singer-based ELT tool, but has since changed their protocol and connectors to be different. Airbyte has kept Singer compatibility so that it can support Singer taps as needed. Airbyte has also kept many of the same principles, including being batch-based. This is eventually where Airbyte’s limitations come from as well.

If you go by pricing calculators and customers, Airbyte is the second-lowest-cost vendor in the evaluation after Estuary.

• Ease of use: Airbyte is an easy-to-use (harder to operate), modern ELT product.
• Open source: Airbyte is open source, which means you can self-host. In addition, open source has fewer limits, such as being able to run more frequent batch intervals.
• Low cost: Airbyte Cloud is one of the lowest-cost options for batch ETL.
• Widely used: Even though Airbyte is only 4 years old, it is widely used. Most of the customers use the open-source version. The official 1.0 product launch, the big milestone for any open-source project, was September, 2024.

• Only 50+ managed connectors: While Airbyte lists 500+ connectors, only 50+ of these are connectors actively developed by Airbyte. The rest are open source connectors listed as Marketplace connectors for Airbyte Cloud. Make sure you evaluate the connectors based on your needs.
• High Latency: While Airbyte has CDC source connectors mostly built on Debezium (except for a new Postgres CDC connector), and a Kafka source connector, everything is loaded in intervals of 5 minutes or more with the open source version. Airbyte Cloud is much worse. It only supports 1+ hour intervals and one source connector at a time. There is no staging or storage, so if something goes wrong with either source or target the pipeline stops. 
  Also, Airbyte is pulling from source connectors in batch intervals. When using CDC, this can put a load on the source databases. In addition, because all Airbyte CDC connectors (other than the new Postgres connector) use Debezium, it is not exactly-once, but at-least-once guaranteed delivery. Latency is also made worse with batch ELT because you need to wait for loads and transforms in the target data warehouse.
• Reliability: There are some issues with reliability you will need to manage. Most CDC sources, because they’re built on Debezium, only ensure at-least-once delivery. It means you will need to deduplicate (dedup) at the target. Airbyte does have both incremental and deduped modes you can use though. You just need to remember to turn them on. Also, Debezium does put less of a load on a source because it uses Kafka. This does make it less of a load on a source than Fivetran CDC. A bigger reliability issue is failure of under-sized workers. There is no scale-out option. Once a worker gets overloaded you will have reliability issues (see scalability). There is also no staging or storage within an Airbyte pipeline to preserve state. If you need the data again, you’ll have to re-extract from the source.
• Scalability: Airbyte is not known for scalability. It has scalability issues that may not make it suitable for your larger workloads. For example, each Airbyte operation of extracting from a source or loading into a target is done by one worker. The source worker is generally the most important component, and its most important component is memory. The source worker will read up to 10,000 records into memory, which could lead to GBs of RAM. By default only 25% of each instance’s memory is allocated to the worker container, which you have little control over in Airbyte Cloud.
  Airbyte is working on scalability. The new PostgreSQL CDC connector does have improved performance. Its latest benchmark as of the time of this writing produced 9MB/sec throughput, higher than Fivetran’s (non HVR) connector. But this is still only 0.5TB a day or so depending on how loads vary throughout the day.
• ELT only: Airbyte cloud supports dbt cloud. This is different from dbt core used by Fivetran. If you have implemented on dbt core in a way that makes it portable (which you should) the move can be relatively straightforward. But if you want to implement transforms outside of the data warehouse, Airbyte does not support that.
• DataOps: Airbyte provides UI-based replication designed for ease of use. It does not give you an “as code” mode that helps with automating end-to-end pipelines, adding tests, or managing schema evolution. But there is Octavia which acts as a CLI for Airbyte.

Airbyte starts at $10 per GB of data moved from a database, and $15 per million rows of data moved via an API (or custom source). There are volume-based discounts. You do pay for backfills as well. While this is solely volume-based, Estuary becomes less expensive for 10s of GB per month.

Debezium started within Red Hat following the release of Kafka, and Kafka Connect. It was inspired in part by Martin Kleppmann’s presentations on CDC and turning the database inside out.

Debezium is the open-source option for general-purpose replication, and it does many things right for replication, from scaling to incremental snapshots (make sure you use DDD-3 and not whole snapshotting). If you are committed to open source, have the specialized resources needed, and need to build your own pipeline infrastructure for scalability or other reasons, Debezium is a great choice.

Otherwise, think twice about using Debezium because it will be a big investment in specialized data engineering and admin resources. While the core CDC connectors are solid, you will need to build the rest of your data pipeline including:

• The many non-CDC source connectors you will eventually need. You can leverage all the Kafka Connect-based connectors to over 100 different sources and destinations. But they have a long list of limits (see confluent docs on limits).
• Data schema management and evolution - while the Kafka Schema Registry does support message-level schema evolution, the number of limitations on destinations and the translation from sources to message makes this much harder to manage.
• Kafka does not save your data indefinitely. There is no replay/backfilling service that manages previous snapshots and allows you to reuse them, or do time travel. You will need to build those services.
• Backfilling and CDC happens on the same topic. So if you need to redo a snapshot, all destinations will get it. If you want to change this behavior you need to have separate source connectors and topics for each destination, which adds costs and source loads.
• You will need to maintain your Kafka cluster(s), which is no small task.

If you are already invested in Kafka as your backbone, it does make good sense to evaluate Debezium.

• Real-Time CDC: Kafka + Debezium captures database changes in real-time.
• Flexibility: Debezium supports multiple databases and allows for flexible configuration options for filtering and handling database changes.
• Scalable Data Streams: Kafka’s distributed architecture ensures that even high-velocity data streams are processed efficiently and can scale horizontally.

• Complex Setup: Managing a self-hosted Kafka cluster alongside Debezium requires significant operational effort, including scaling, monitoring, and ensuring fault tolerance.
• At-Least-Once Delivery: Debezium guarantees at-least-once delivery, meaning duplicate records may need to be handled at the consumer level. This adds complexity to building exactly-once data pipelines.
• High Infrastructure Costs: Running a Kafka cluster and Debezium connectors, especially at scale, can require substantial infrastructure resources, making it more costly than other CDC alternatives.

Kafka itself is open-source and free to use, but the costs associated with deploying and maintaining a Kafka cluster can vary depending on cloud or on-premise infrastructure. Managed Kafka services such as Confluent Cloud can provide a more streamlined, albeit pricier, solution. Debezium is open-source, but operational costs come from the Kafka infrastructure and any associated storage, processing, and egress costs.

Estuary is the right-time data platform that replaces fragmented data stacks with one dependable system for data movement. Teams use it to move data from databases, SaaS apps, files, and streams into warehouses, lakes, operational stores, and AI systems at the cadence they choose: sub-second streaming, near real-time, or scheduled batch. Founded in 2019, Estuary is built on Gazette, an open-source streaming broker developed by the same founding team that lets Estuary mix CDC, streaming, and batch in a single catalog with exactly-once delivery, deterministic recovery, and targeted backfills.

Unlike traditional ELT tools that focus on batch loads, Estuary stores every event in collections that can be reused for multiple destinations. Captured changes are written once to durable storage and fanned out to any number of targets without reloading the source, which reduces load on primary systems and makes replay easy when schemas change. Estuary runs as a multi-tenant cloud service, private data plane, or BYOC, and ships with 200+ fully-managed native connectors plus support for open-source Airbyte, Meltano, and Stitch connectors.

For AI-native workflows, Estuary ships Agent Skills that work with Claude Code, Cursor, OpenAI Codex, GitHub Copilot, and Gemini CLI, letting developers create captures, materialize into Snowflake, BigQuery, Redshift, or Databricks, and troubleshoot pipelines through natural-language prompts. A separate MCP server handles docs-aware Q&A inside the same assistants.

Customers include Glossier, which cut data costs by 50%; Xometry, which reduced integration costs by 60% with private deployment; Headset, which cut Snowflake ingestion costs by 40% after replacing Airbyte; and Prodege, which built Apache Iceberg pipelines.

• Right-time pipelines from millisecond streaming to scheduled batch. Choose cadence per pipeline so cost and freshness match each workload. Most ELT tools default to 15-minute or hourly intervals.
• One platform for CDC, batch, and streaming. Replaces the typical 3-4 tool stack of Debezium plus Kafka plus Airbyte plus dbt with a single system, reducing tool sprawl and operational overhead.
• Dependable replication built on Gazette. Exactly-once delivery, deterministic recovery, and targeted backfills keep pipelines stable through schema changes and source failures.
• Efficient log-based CDC with collection reuse. Captures inserts, updates, and deletes once, then fans out to any number of destinations without re-reading the source database, reducing load on production systems.
• Predictable usage-based pricing. $0.50 per GB moved plus $100 per connector instance per month for the first 6 instances, then $50 per instance for additional ones. No MAR-based surprises and no per-row charges.
• Agent-native developer experience. Open-source Agent Skills let Claude Code, Cursor, OpenAI Codex, GitHub Copilot, and Gemini CLI build and operate Estuary pipelines from natural language, with an MCP server for docs-aware Q&A in the same tools.

• No graphical transformation UI. Estuary focuses on SQL and TypeScript transformations alongside dbt integration. Teams that need point-and-click visual ETL like Matillion or Informatica PowerCenter will find this a gap, though dbt covers most warehouse-side needs.
• On-premises connectivity is narrower than legacy ETL vendors. For mainframe, SAP ECC on-premises, or other proprietary on-premises systems, vendors like Informatica or Talend may have broader native coverage. Verify legacy on-premises coverage during evaluation.
• Smaller market presence than category incumbents. Fivetran, Informatica (now Salesforce), and Talend (now Qlik) have larger enterprise customer bases and longer procurement track records. Estuary fits teams able to evaluate on technical merit, but buyers requiring a Gartner Magic Quadrant leader may need to factor this in.

Estuary uses a straightforward usage-based pricing model. Data movement is charged at $0.50 per GB sourced or delivered. Connector instances are $100 per month for the first 6 instances, then $50 per month for each additional instance. A Developer tier is free indefinitely up to 10 GB per month and 2 concurrent connector instances, and Cloud-tier customers can request a 30-day free trial.

Use the Estuary pricing calculator to model your specific workload. For larger deployments, Enterprise plans add volume-based discounts, SOC 2 and HIPAA compliance reports, SSO, custom SLA terms, private deployments, and dedicated support.