Comparing Alooma with Census and Weld
Carolina Russ6 min read
What is Alooma
Alooma (acquired by Google Cloud in 2019) was a streaming ETL platform that enabled real-time ingestion of data from various sources into BigQuery. It provided a visual pipeline editor to map, transform, and route data with minimal code, automatically handling schema changes and ensuring exactly-once delivery. While Alooma as a standalone product is retired, many of its features have been integrated into Google Cloud’s Dataflow and Pub/Sub pipelines.
Pros
- Real-time streaming ETL with automatic schema drift handling.
- Minimal coding: visual pipeline UI with built-in connectors to databases, Kafka, APIs, and SaaS apps.
- Exactly-once delivery guarantees to BigQuery, eliminating duplicate data.
Cons
- Standalone Alooma product is discontinued—functionality now lives in GCP services (e.g., Dataflow, Data Fusion).
- Migrating legacy Alooma pipelines to GCP-native services requires rework, as UI and features differ from original Alooma.
Google Cloud’s Dataflow (Alooma integration):
What I like about Alooma
Alooma’s ease of connecting live streaming data sources directly into BigQuery with automated schema management was revolutionary for our real-time analytics.
What I dislike about Alooma
Since Google integrated Alooma into its native services, the standalone product no longer exists, so new users must migrate to Dataflow or Data Fusion.
What is Census
Census is a leading Reverse ETL platform that syncs data from your data warehouse back into SaaS tools like Salesforce, HubSpot, and Marketo. It integrates deeply with dbt and modern warehouses, enabling no-code mapping, incremental upserts, and reliable syncs to operational systems in near real time.
Pros
- Warehouse-centric: works directly on tables or dbt models
- No-code field mapping with live previews
- Broad destination support: Salesforce, HubSpot, Slack, Google Sheets, etc.
- Incremental upserts ensure data consistency with no duplicates
- Deep dbt integration and “analytics-as-code” workflows (YAML config)
- Flexible scheduling and API triggers for near real-time use cases
Cons
- Focuses only on reverse ETL—requires a separate ELT tool for ingestion
- Pricing based on rows or syncs can be expensive at very large volumes
- Complex transformations must be done upstream in the warehouse/dbt
- Dependent on destination API rate limits, which can slow large syncs
- SaaS-only (no on-prem deployment)
Census Overview (G2):
What I like about Census
Census is the fastest and most reliable reverse ETL platform with 99.5% uptime and premium support for all plans. It delivers transformed data at time-of-use—fueling rapid data activation in operational tools without relying on leaky pipelines.
What I dislike about Census
What is Weld
Weld is a powerful ETL platform that seamlessly integrates ELT, data transformations, reverse ETL, and AI-assisted features into one user-friendly solution. With its intuitive interface, Weld makes it easy for anyone, regardless of technical expertise, to build and manage data workflows. Known for its premium quality connectors, all built in-house, Weld ensures the highest quality and reliability for its users. It is designed to handle large datasets with near real-time data synchronization, making it ideal for modern data teams that require robust and efficient data integration solutions. Weld also leverages AI to automate repetitive tasks, optimize workflows, and enhance data transformation capabilities, ensuring maximum efficiency and productivity. Users can combine data from a wide variety of sources, including marketing platforms, CRMs, e-commerce platforms like Shopify, APIs, databases, Excel, Google Sheets, and more, providing a single source of truth for all their data.
Pros
- Premium quality connectors and reliability
- User-friendly and easy to set up
- AI assistant
- Very competitive and easy-to-understand pricing model
- Reverse ETL option
- Lineage, orchestration, and workflow features
- Advanced transformation and SQL modeling capabilities
- Ability to handle large datasets and near real-time data sync
- Combines data from a wide range of sources for a single source of truth
Cons
- Requires some technical knowledge around data warehousing and SQL
- Limited features for advanced data teams
A reviewer on G2 said:
What I like about Weld
First and foremost, Weld is incredibly user-friendly. The graphical interface is intuitive, which makes it easy to build data workflows quickly and efficiently. Even with little experience in SQL and pipeline management, we found that Weld was straightforward and easy to use. What really impressed me, however, was Weld's flexibility. It was able to handle data from a wide variety of sources, including SQL databases, Google Sheets, and even APIs. The solution also allowed us to customize my data transformations in a way that best suited my needs. Whether I needed to clean data, join tables, or aggregate data, Weld had the necessary tools to accomplish the task. Weld's performance was also exceptional. I was able to run large-scale ETL jobs quickly and efficiently, with minimal downtime via a Snowflake instance and visualization via own-hosted Metabase. The solution's scalability meant that I could process more data without any issues. Another standout feature of Weld was its support. I never felt lost or unsure about how to use a particular feature, as the support team was always quick to respond to any questions or concerns that I had. Overall, I highly recommend Weld as an ETL solution. Its user-friendliness, flexibility, performance, and support make it an excellent choice for anyone looking to streamline their data integration processes. I will definitely be using Weld for all my ETL needs going forward.
What I dislike about Weld
Weld is still limited to a certain number of integrations - although the team is super interested to hear if you need custom integrations.
Alooma vs Census: Ease of Use and User Interface
Alooma
Alooma’s web-based pipeline builder allowed users to drag-and-drop connectors for streaming or batch data, apply transformations, and route data to BigQuery with just a few clicks. The interface auto-generated SQL when possible.
Census
Census provides an intuitive UI for mapping warehouse fields to destination fields, with live previews—non-technical business users quickly adopt it for operational data syncs.
Alooma vs Census: Pricing Transparency and Affordability
Alooma
No longer available as a separate product. Users adopt equivalent GCP services (Dataflow, Data Fusion) which have pay-as-you-go pricing under the GCP pricing model.
Census
While there’s a free tier to get started, professional plans based on usage can add up for large enterprises. Still, ROI often justifies the investment by automating data activation in CRM/marketing tools.
Alooma vs Census: Comprehensive Feature Set
Alooma
Alooma supported real-time ingestion from Kafka, databases (MySQL, PostgreSQL), logs, REST APIs, and SaaS apps, with built-in transformations (masking, enrichment). It automatically handled schema changes, and could write to BigQuery partitions.
Census
Census focuses on reverse ETL: no-code mapping, incremental upserts keyed on primary keys, scheduling, and deep dbt integration. It provides monitoring dashboards, alerting, and a CLI/API for GitOps workflows.
Alooma vs Census: Flexibility and Customization
Alooma
Users could write custom JavaScript transforms or Python UDFs for complex logic. The platform managed infrastructure, but custom connectors required Eloqua code or support.
Census
Mapping logic is as flexible as your SQL—any complex query can feed Census. Users can customize scheduling (cron or event triggers) and configure failure handling. It adapts well but relies on warehouse transformations for complex logic.
Summary of Alooma vs Census vs Weld
| Weld | Alooma | Census | |
|---|---|---|---|
| Connectors | 200++ | 100+ | 130+ |
| Price | €99 / Unlimited usage | N/A (product retired; GCP service pricing applies) | Free tier; Pro ~$350/mo for 2 destinations |
| Free tier | No | No | Yes |
| Location | EU | Sunnyvale, CA, USA (pre-acquisition) | US |
| Extract data (ETL) | Yes | Yes | No |
| Sync data to HubSpot, Salesforce, Klaviyo, Excel etc. (reverse ETL) | Yes | No | Yes |
| Transformations | Yes | Yes | No |
| AI Assistant | Yes | No | No |
| On-Premise | No | No | No |
| Orchestration | Yes | Yes | Yes |
| Lineage | Yes | No | No |
| Version control | Yes | No | Yes |
| Load data to and from Excel | Yes | No | No |
| Load data to and from Google Sheets | Yes | No | Yes |
| Two-Way Sync | Yes | No | No |
| dbt Core Integration | Yes | No | Yes |
| dbt Cloud Integration | Yes | No | No |
| OpenAPI / Developer API | Yes | No | Yes |
| G2 Rating | 4.8 | 4.5 |
Conclusion
You’re comparing Alooma, Census, Weld. Each of these tools has its own strengths:
- Alooma: alooma supported real-time ingestion from kafka, databases (mysql, postgresql), logs, rest apis, and saas apps, with built-in transformations (masking, enrichment). it automatically handled schema changes, and could write to bigquery partitions. . no longer available as a separate product. users adopt equivalent gcp services (dataflow, data fusion) which have pay-as-you-go pricing under the gcp pricing model. .
- Census: census focuses on reverse etl: no-code mapping, incremental upserts keyed on primary keys, scheduling, and deep dbt integration. it provides monitoring dashboards, alerting, and a cli/api for gitops workflows.. while there’s a free tier to get started, professional plans based on usage can add up for large enterprises. still, roi often justifies the investment by automating data activation in crm/marketing tools..
- Weld: weld integrates elt, data transformations, and reverse etl all within one platform. it also provides advanced features such as data lineage, orchestration, workflow management, and an ai assistant, which helps in automating repetitive tasks and optimizing workflows.. weld offers a straightforward and competitive pricing model, starting at €99 for 2 million active rows, making it more affordable and predictable, especially for small to medium-sized enterprises..
