LocalStack vs Gretel.ai

From $39 per licence/month (Base, billed annually; $45 monthly)

Quote on request

Plans are Hobby (free, non-commercial), Base $39 and Ultimate $89 per licence/month billed annually, then Enterprise. Commercial use needs a paid licence, and the higher tiers are what unlock advanced IAM enforcement and the wider service coverage.

The old credit-based self-serve tier is gone. The successor microservices are licensed through NVIDIA AI Enterprise; NeMo Data Designer can be tried on build.nvidia.com.

Hobby tier is free but explicitly non-commercial, and LocalStack has said the Community emulator will no longer receive product updates.

Category standard

LocalStack · since 2017

Emerging

NVIDIA (formerly Gretel) · since 2019

• Integration tests against AWS services run offline in seconds at no cloud cost.
• Removes the shared-sandbox-account contention that plagues cloud teams.
• Works with Terraform and CDK, so infrastructure code is testable.

• Formal differential-privacy guarantees rather than best-effort masking, now via DP-SGD in NeMo Safe Synthesizer.
• Synthetic data preserves statistical relationships useful for analytics and model training.
• Backed by NVIDIA's platform investment rather than a single startup's runway.

• No longer open source: the Community edition is end-of-life, the repo is archived, and running it now requires an account and auth token.
• Using it in CI counts as commercial use, so the free tier does not cover the case most teams want it for.
• Emulation is not identical to AWS; some behaviours and IAM semantics differ.

• No longer buyable as Gretel — you are procuring NVIDIA AI Enterprise, which is far heavier than the old self-serve signup.
• Model training adds time and cost compared to rule-based masking.
• Safe Synthesizer trains on a real dataset, so it does not help with greenfield data that does not exist yet.

AWS-native teams whose tests currently depend on a shared cloud account, and who are willing to pay for a licence now that the free community route has closed.

Regulated enterprises already standardising on NVIDIA AI Enterprise. Teams that wanted Gretel's self-serve tier should look at Tonic or Neosync instead.