Cloud providers like AWS, GCP, and Azure should offer local emulators for development. This would encourage developers to utilize their services more.
I currently work with several AWS serverless stacks that are challenging or even impossible to integration test locally. While Localstack provide a decent solution, it seems like a service that AWS should offer to enhance the developer experience. They’d also be in the best position to keep it current.
A few notes about "local AWS" (or "local cloud") based on other comments and my own XP:
- I'm not sure this kind of product is really a foot in the door to create new customers. Someone not willing to create an actual account because they have no money or they just don't want to put their card details is not someone who's going to become a 6 figures per year customer, which is the level to be noticed by those providers.
- The free tier of AWS is actually quite generous. For my own needs I spend less than $10/year total spread around dozens of accounts.
- If one wants to learn AWS, they MUST learn that there are no hard spend limits, and the only way to actually learn it, is to be bitten by it as early as possible. It's better to overspend $5 at the beginning of the journey than to overspend $5k when going to prod.
- The main interest of local cloud is actually to make things easier and iterating faster, because you don't focus on all the security layer. Since everything is local, focus on using the services, period. Meanwhile, if you wanted to rely on actual dev accounts, you need to first make sure that everything is secure. With local cloud you can skip all this. But then, if you decide to go live, you have to fix this security debt and it most often than not break things that "work on my computer".
- Localstack has the actual support of AWS, that's why they have so much features and are able to follow the releases of the services. I doubt this FOSS alternative will have it.
How's this compare to moto? I understand folks are upset about licensing changes for LocalStack (which I happily use at my day job with an enterprise license), but there are already several good alternatives.
The aws endpoint coverage is impressive for moto [1], which my team almost migrated to, but we liked our support contract with LocalStack.
If you want to use that for unit testing, then I think it would be better to mock the calls to AWS services. That way you test only your implementation, in an environment you control.
If you want to use that for local development, then I think it would be better to provision a test environment (using Terraform or any other IaC tool). That way you don't run the risk of a bug slipping into prod because the emulator has a different behaviour than the real service.
> LocalStack's community edition sunset in March 2026 — requiring auth tokens, dropping CI support, and freezing security updates. Floci is the no-strings-attached alternative.
This project would be comical if it takes off. In Romanian this name means "a small pile of hair", but informally it's only used as a synonym for pubic hair.
Although I love localstack and am grateful for what they have done, I always thought that an open community-driven solution would be much more suitable and opens a lot of doors for AWS engineers to contribute back. I’m certain that it’s on their best interest to do so (specially as many of their popular products have local versions)
It’s a no-brainer to me as AI adoption continues to increase: local-first integration testing is a must and teams that are equipped to do so will be ahead of everyone else
We wrote a detailed breakdown of Floci's specs vs LocalStack — the 408/408 SDK test pass rate, 24ms vs 3.3s startup, services LocalStack community edition doesn't cover (API Gateway v2, Cognito, RDS with IAM auth): https://megaoneai.com/spotlight/floci-free-aws-emulator-alte...
Cool, I've tried localstack before and cant wait to give it a try
Anyway, do anyone know if there're similar stuff but for gcp? So far https://github.com/goccy/bigquery-emulator helped me a lot in emulating bigquery behaviour, but I cant find emulator for the whole gcp environment.
Local AWS emulators are one of those tools where the value is inversely proportional to how much you trust your staging environment. If your staging account perfectly mirrors prod, you don't need a local emulator. But nobody's staging perfectly mirrors prod, so you end up needing something like this for the fast feedback loop on IAM policies, Step Functions state machines, and anything involving SQS/SNS fanout where the iteration cycle against real AWS is measured in minutes per attempt. The question is always parity — how closely does the emulation match real AWS behavior at the edges? LocalStack has been chasing that for years and still hits gaps. Curious how Floci handles the services where AWS's own behavior is underdocumented.
At that speed you can treat it as disposable: fresh instance per test run, no shared state, no flaky tests from leftover S3 objects. that was never practical with LocalStack cold start
95 comments
I currently work with several AWS serverless stacks that are challenging or even impossible to integration test locally. While Localstack provide a decent solution, it seems like a service that AWS should offer to enhance the developer experience. They’d also be in the best position to keep it current.
- I'm not sure this kind of product is really a foot in the door to create new customers. Someone not willing to create an actual account because they have no money or they just don't want to put their card details is not someone who's going to become a 6 figures per year customer, which is the level to be noticed by those providers.
- The free tier of AWS is actually quite generous. For my own needs I spend less than $10/year total spread around dozens of accounts.
- If one wants to learn AWS, they MUST learn that there are no hard spend limits, and the only way to actually learn it, is to be bitten by it as early as possible. It's better to overspend $5 at the beginning of the journey than to overspend $5k when going to prod.
- The main interest of local cloud is actually to make things easier and iterating faster, because you don't focus on all the security layer. Since everything is local, focus on using the services, period. Meanwhile, if you wanted to rely on actual dev accounts, you need to first make sure that everything is secure. With local cloud you can skip all this. But then, if you decide to go live, you have to fix this security debt and it most often than not break things that "work on my computer".
- Localstack has the actual support of AWS, that's why they have so much features and are able to follow the releases of the services. I doubt this FOSS alternative will have it.
The aws endpoint coverage is impressive for moto [1], which my team almost migrated to, but we liked our support contract with LocalStack.
http://docs.getmoto.org/en/latest/docs/services/index.html
If you want to use that for unit testing, then I think it would be better to mock the calls to AWS services. That way you test only your implementation, in an environment you control.
If you want to use that for local development, then I think it would be better to provision a test environment (using Terraform or any other IaC tool). That way you don't run the risk of a bug slipping into prod because the emulator has a different behaviour than the real service.
> LocalStack's community edition sunset in March 2026 — requiring auth tokens, dropping CI support, and freezing security updates. Floci is the no-strings-attached alternative.
Although I love localstack and am grateful for what they have done, I always thought that an open community-driven solution would be much more suitable and opens a lot of doors for AWS engineers to contribute back. I’m certain that it’s on their best interest to do so (specially as many of their popular products have local versions)
It’s a no-brainer to me as AI adoption continues to increase: local-first integration testing is a must and teams that are equipped to do so will be ahead of everyone else
Anyway, do anyone know if there're similar stuff but for gcp? So far https://github.com/goccy/bigquery-emulator helped me a lot in emulating bigquery behaviour, but I cant find emulator for the whole gcp environment.
At that speed you can treat it as disposable: fresh instance per test run, no shared state, no flaky tests from leftover S3 objects. that was never practical with LocalStack cold start
https://news.ycombinator.com/item?id=47420619
https://github.com/robotocore/robotocore