As senior engineers evaluating open-source time-series databases, a comparison of Apache HoraeDB (incubating) and SiriDB reveals distinct profiles in momentum, community size, and apparent use cases. Apache HoraeDB boasts 2,834 stars, with a notable 8 stars added in the last 30 days, indicating a moderate and growing momentum. This suggests a sizable, albeit not extremely large, community around the project, potentially attracting more contributors and users due to its Apache incubation status. Its cloud-native, distributed architecture positions it well for large-scale, modern infrastructure deployments, particularly in environments already invested in the Apache ecosystem. In contrast, SiriDB stands at 511 stars with no additions in the last 30 days, suggesting a smaller, more stagnant community and lower current momentum. Despite this, its unique technical features (lack of a global index, dynamic on-the-fly resource addition, and a bespoke query language for dynamic grouping) may appeal to specific, possibly niche use cases requiring high scalability and custom analytics capabilities without the overhead of a global index. This could suit specialized applications or teams seeking to leverage its distinctive architectural advantages. The choice between the two may hinge on whether the project's integration with broader Apache technologies and a growing community (Apache HoraeDB) is more valuable than the innovative, albeit less actively maintained, solution (SiriDB) for particular scalability and query requirements.