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Floci – A free, open-source local AWS emulator

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Re: Floci – A free, open-source local AWS emulator

#81

Post by [deleted] »

mdavid626 wrote: post #77
jeroenhd wrote: post #55

Earlier quoted context omitted.

Getting Java to run is a base requirement for running most software written in Java. However, there is a dedicated Dockerfile for creating a native image (Java words for "binary") that shouldn't require a JVM. I haven't tested running the binary myself so it's possible there are dependencies I'm not aware of, but I'm pretty sure you can just grab the binary out of the container image and run there locally if you want…

Yeah, compare this with downloading single binary approach. Downloading JDK, setting up the correct env variables, or running Docker, all this is just pain, compared to single binary approach.

[deleted]

Re: Floci – A free, open-source local AWS emulator

#82

Post by useftmly »

Longwelwind wrote: post #65

Those kind of tools are futile endeavors to me. 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…

[dead]

Re: Floci – A free, open-source local AWS emulator

#83

Post by drzaiusx11 »

cosmotic wrote: post #51
thezenmonsta wrote: post #50

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…

Relying on staging means no offline development and also leads to toe-stepping. Cheap local implementations are great for consistent tests.

100% this. I've used AWS emulation layers for local-first development going on the better part of a decade. I cannot stress how much time it saves me from pushing code that would have failed in staging. When the cost of deployment pipelines via cloudformation is so high, it's a no brainer.

DIY mocks alone can get you somewhat there, but that relies on the developer having intimate knowledge of the aws sdk under test and it's very easy to mock the inputs and outputs wrong. I'd rather defer that to an emulation layer that does that mimicry better than my guess and check with 30m between attempts when my cloudformation deployments ultimately fail...

Re: Floci – A free, open-source local AWS emulator

#84

Post by drzaiusx11 »

seer wrote: post #35
kay_o wrote: post #3

is all of this is vibe coded?

Isn’t a “local emulator of cloud services” kind of the perfect project to be vibe coded? Extremely well documented surface to implement, very easy to test automatically and prove it matches the spec, and if you make some things sub optimal performance wise, that is totally fine because by project will not be used in a tight loop anyway - e.g. it will just need to be faster than over the network hop plus the time it t…

AWS _does_ officially provide local-first dev containers for services like DynamoDB but sadly not every AWS service comes with those. Why? I have no idea, like you said it's clearly feasible and they already do it for some services today...

Re: Floci – A free, open-source local AWS emulator

#85

Post by drzaiusx11 »

drzaiusx11 wrote: post #75
4riel wrote: post #47

24ms startup is the real story 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

This is why I use LocalStack today. I can stand up all my infra for my teams 14 microservices in under 30s and test my in flight changes, all without an internet connection. Deploying to our real staging environments take 30m (literally) for a single CDK / cloudformation stack change. The fact I have an immediate feedback loop saves my team inordinate amounts of time. Cloudformation deployments are criminally slow. I…

Side note: this local-first strategy works well but requires some beefy hardware with gobs of ram, at least in my line of work with java and rails microservices. My laptop is an M4 with 64gb ram. I honestly wish I had the 128GB model...

Re: Floci – A free, open-source local AWS emulator

#86

Post by drzaiusx11 »

mdavid626 wrote: post #77
jeroenhd wrote: post #55

Earlier quoted context omitted.

Getting Java to run is a base requirement for running most software written in Java. However, there is a dedicated Dockerfile for creating a native image (Java words for "binary") that shouldn't require a JVM. I haven't tested running the binary myself so it's possible there are dependencies I'm not aware of, but I'm pretty sure you can just grab the binary out of the container image and run there locally if you want…

Yeah, compare this with downloading single binary approach. Downloading JDK, setting up the correct env variables, or running Docker, all this is just pain, compared to single binary approach.

Isn't a docker image basically a universal binary at this point? It's a way to ship a reproducible environment with little more config than setting an ENV var or two. All my local stuff runs under a docker compose stack so I have a container for the db, a container for redis, LocalStack, etc

Re: Floci – A free, open-source local AWS emulator

#87

Post by thinkthatover »

hrmtst93837 wrote: post #66
cebert wrote: post #12

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…

[flagged]

what makes you think AWS would look at any of the bugs filed by people using local emulators

Re: Floci – A free, open-source local AWS emulator

#88

Post by littlestymaar »

hrmtst93837 wrote: post #66
cebert wrote: post #12

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…

[flagged]

“A trillion dollar company cannot afford bug triage” is a weird argument tbh.

Re: Floci – A free, open-source local AWS emulator

#89

Post by autotune »

stevekemp wrote: post #56

Looking at the features this seems to be an awesome project, but the commit history (even on the develop branch) shows almost nothing. No pull-requests, no real issues, it smells like it was auto-generated which is disappointing. Makes it harder to trust if you're going to test with "real data", how do we know it won't be sent elsewhere?

Definitely this. I like seeing issues reasonably populated with OSS projects. Otherwise, how am I supposed to contribute back to it? Granted it's a newer project so I will be keeping track in the future.

Re: Floci – A free, open-source local AWS emulator

#90

Post by mdavid626 »

drzaiusx11 wrote: post #86
mdavid626 wrote: post #77

Earlier quoted context omitted.

Yeah, compare this with downloading single binary approach. Downloading JDK, setting up the correct env variables, or running Docker, all this is just pain, compared to single binary approach.

Isn't a docker image basically a universal binary at this point? It's a way to ship a reproducible environment with little more config than setting an ENV var or two. All my local stuff runs under a docker compose stack so I have a container for the db, a container for redis, LocalStack, etc

Is it though?

On my Mac Docker runs Linux virtualized. It’s a resource hog.

Compare that with simple native binary.

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