Best Open Serverless (osls) Alternatives in 2026
The top Open Serverless (osls) alternatives are Serverless Framework, AWS Serverless Application Model (AWS SAM) and Apache OpenWhisk: 15 serverless development frameworks our editors would look at instead of Open Serverless (osls), in our ranking order.
Open Serverless (osls): A YAML-based framework for packaging and locally running AWS Lambda services. Where it falls short: deployment targets are limited to AWS.
Switching from Open Serverless (osls)? For most serverless development frameworks buyers the best Open Serverless (osls) alternative is Serverless Framework, built for teams deploying AWS serverless apps with YAML.
Why People Look for an Open Serverless (osls) Alternative
- Deployment targets are limited to AWS
- The project prioritizes maintenance over major new feature areas
- AWS infrastructure and usage may incur separate charges
- No kubernetes support — 1 of the alternatives below has it
Quick Picks by What You Need
- Best overallServerless Framework9.2
Teams deploying AWS serverless apps with YAML
Visit Serverless Framework - Lowest priceServerless Framework9.2
Paid plans from $142/mo
Visit Serverless Framework - Best free optionServerless Framework9.2
Has a free plan
Visit Serverless Framework - Best for kubernetes supportNitric7.8
Kubernetes support (Open Serverless (osls): no)
Visit Nitric
All 15 Open Serverless (osls) Alternatives, Ranked
Advertiser disclosure: iTechGuides is reader-supported. Vendors can pay for top positions in our rankings and for a place on other products' pages, and we may earn a commission when you click some links. Bought places stand at the number bought; this page and our disclosure say so. Paying vendors may get a fuller, more detailed review from our editors, and that review can change their score. How we rank.
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Best forTeams deploying AWS serverless apps with YAML
- Better than Open Serverless (osls):
- Editor score 9.2 vs 6.4
An open-source, YAML-driven AWS framework with optional hosted deployment and monitoring tools.
9.2/10★★★★★Visit site -
Best forAWS teams wanting templates and local debugging
- Better than Open Serverless (osls):
- Editor score 9.1 vs 6.4
A free AWS-focused toolkit for defining, deploying, and locally debugging serverless apps.
9.1/10★★★★★Visit AWS SAM -
Best forTeams building portable event-driven functions
- Better than Open Serverless (osls):
- Editor score 8.8 vs 6.4
A portable, self-managed framework for event-driven functions, with Kubernetes and Docker support.
8.8/10★★★★☆Try Apache OpenWhisk -
Best forJava teams targeting several cloud function providers
- Better than Open Serverless (osls):
- Editor score 8.7 vs 6.4
An open-source Spring programming model for packaging and adapting Java functions across clouds.
- Local testing
- Application packaging
8.7/10★★★★☆Visit site -
Best forJava teams building cloud-native applications and functions
- Better than Open Serverless (osls):
- Editor score 8.6 vs 6.4
An open-source Java and Kotlin framework with Kubernetes tooling, not a serverless deployment workflow.
8.6/10★★★★☆Visit Quarkus -
Best forTeams deploying containerized functions on Kubernetes
- Better than Open Serverless (osls):
- Editor score 8.4 vs 6.4
A self-hosted, container-based serverless platform with broad Kubernetes targets and paid scale-to-zero.
8.4/10★★★★☆Visit OpenFaaS -
Best forKubernetes teams needing scalable event-triggered functions
- Better than Open Serverless (osls):
- Editor score 8.2 vs 6.4
A self-hosted way to run event-triggered functions on Kubernetes, with automatic scaling.
8.2/10★★★★☆Visit Fission -
Best forTeams running containerized functions across environments
- Better than Open Serverless (osls):
- Editor score 8.1 vs 6.4
A self-hosted, container-native Functions-as-a-Service platform for deployment across environments.
8.1/10★★★★☆Visit Fn Project -
Best forTeams seeking Go or TypeScript cloud infrastructure
- Better than Open Serverless (osls):
- Editor score 8.0 vs 6.4
A Go and TypeScript backend platform that automates infrastructure, deployment, and observability.
8.0/10★★★★☆Visit Encore -
Best forTeams deploying functions across cloud providers
- Better than Open Serverless (osls):
- Editor score 7.9 vs 6.4
A multi-cloud serverless CLI with templates, YAML tools, and local debugging.
- Local testing
7.9/10★★★★☆Try Serverless Devs -
Best forTeams building backends for multiple cloud providers
- Better than Open Serverless (osls):
- Kubernetes support
- Editor score 7.8 vs 6.4
An open-source framework for declaring, locally testing and deploying cloud backends across providers.
- Kubernetes support
- Local testing
- Application packaging
7.8/10★★★★☆Visit Nitric -
Best forTeams deploying Next.js applications on AWS
- Better than Open Serverless (osls):
- Editor score 7.7 vs 6.4
Deploy Next.js to AWS with infrastructure defined in TypeScript and an optional Console.
7.7/10★★★★☆Visit SST -
Best forSmall teams building AWS apps with a local simulator
- Better than Open Serverless (osls):
- Editor score 7.6 vs 6.4
Manifest-based AWS app development with local Lambda emulation and AWS deployment.
- Local testing
- Application packaging
7.6/10★★★★☆Visit Architect -
Best forPython teams wanting a simple AWS Lambda workflow
- Better than Open Serverless (osls):
- Editor score 7.5 vs 6.4
A focused Python CLI for building, packaging, and deploying applications to AWS Lambda.
- Local testing
- Application packaging
7.5/10★★★★☆Visit AWS Chalice -
Best forJava teams adapting Micronaut functions to cloud providers
- Better than Open Serverless (osls):
- Editor score 7.3 vs 6.4
An open-source Micronaut option for building Java, Kotlin, and Groovy serverless functions.
- Local testing
- Application packaging
7.3/10★★★★☆Visit Micronaut
Open Serverless (osls) Alternatives: Common Questions
What is the best alternative to Open Serverless (osls)?
Serverless Framework: #1 in our Serverless Development Frameworks ranking, with an editor score of 9.2 out of 10. An open-source, YAML-driven AWS framework with optional hosted deployment and monitoring tools.
Is there a free alternative to Open Serverless (osls)?
Yes. Serverless Framework, AWS Serverless Application Model (AWS SAM), Apache OpenWhisk, Spring Cloud Function and Quarkus have a free plan or a free tier (15 of the 15 alternatives on this page).
What is the cheapest paid alternative to Open Serverless (osls)?
Of the alternatives here that publish a price, Serverless Framework starts lowest, at $142/mo.
Why do people look for Open Serverless (osls) alternatives?
Deployment targets are limited to AWS; The project prioritizes maintenance over major new feature areas; AWS infrastructure and usage may incur separate charges.
How do I switch from Open Serverless (osls)?
Snapshot or back up the data and configs on your Open Serverless (osls) server. Create the new server with the same operating system and size, and add your SSH key. Copy the data across (rsync or your backup tool) and reinstall your apps or containers. Move the DNS records or IP references to the new server, test it, then cancel Open Serverless (osls).
How to Switch from Open Serverless (osls)
- Snapshot or back up the data and configs on your Open Serverless (osls) server.
- Create the new server with the same operating system and size, and add your SSH key.
- Copy the data across (rsync or your backup tool) and reinstall your apps or containers.
- Move the DNS records or IP references to the new server, test it, then cancel Open Serverless (osls).
Open Serverless (osls) vs Each Alternative
| # | Tool | Free plan | Paid from | Score |
|---|---|---|---|---|
| 24 | Open Serverless (osls) | Yes | Free | 6.4 |
| 1 | Serverless Framework | Yes | $142/mo | 9.2 |
| 2 | AWS Serverless Application Model (AWS SAM) | Yes | Free | 9.1 |
| 3 | Apache OpenWhisk | Free | 8.8 | |
| 4 | Spring Cloud Function | Yes | Free | 8.7 |
| 5 | Quarkus | Yes | Free | 8.6 |
| 6 | OpenFaaS | Yes | $1,250/mo | 8.4 |
| 7 | Fission | Free | 8.2 | |
| 8 | Fn Project | Free | 8.1 | |
| 9 | Encore | Yes | 8.0 | |
| 10 | Serverless Devs | Yes | Free | 7.9 |
| 11 | Nitric | Yes | Free | 7.8 |
| 12 | SST | Yes | $0.03/unit usage-based | 7.7 |
| 13 | Architect | Yes | Free | 7.6 |
| 14 | AWS Chalice | Yes | Free | 7.5 |
| 15 | Micronaut Functions | Yes | Free | 7.3 |
Reviewed by iTechGuides Editors · Editorial team · Updated Oct 2026
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