ACID Properties
ACID — Atomicity, Consistency, Isolation, Durability — is the set of guarantees a relational transaction system commits to. Atomicity says all-or-nothing; Consistency says invariants survive; Isolation says concurrent transactions appear serial; Durability says committed writes survive crash. In TantraDev's FinTech work ACID is non-negotiable: money movement without ACID is money loss with a probability density function.
Concepts that travel with this one.
Architecture rarely lives in isolation — these are the terms that come up in the same conversation.
PostgreSQL
PostgreSQL is an open-source relational database with strong ACID guarantees, MVCC concurrency, and rich extension surface (PostGIS, pg_partman, logical replication). It is the default datastore on every TantraDev engagement where the workload is transactional, the data has relationships, and the team needs the option to scale via partitioning and read replicas before reaching for a specialised store.
Eventual Consistency
Eventual consistency is a relaxation of the strong-consistency guarantee: writes propagate asynchronously across replicas, and readers may briefly observe stale state, but the system converges to a single value if writes stop. The CAP-theorem trade-off is throughput and availability under partition. TantraDev uses eventual consistency knowingly — never as a side effect — and always with a documented staleness window.
Building a system where ACID Properties is the load-bearing decision?
30 minutes on the phone, one page in your inbox — what to build, what to skip, what it will cost. You keep the audit even if we are not the right fit.