8 Best Riza Alternatives (2026)

The closest alternatives to Riza are ascii, Blaxel, box and Cloudflare Sandbox, with 4 more below. Each shares a comparison category with it, so every rationale here names both tools' real values. Riza is marked No on Snapshot & fork, where Daytona records Yes, usually where a switch starts.

Website Docs Sandbox providers

Why do people look for Riza alternatives?

Most people searching for Riza alternatives are not shopping, they already run it and something has stopped fitting.
That something is usually a specific number rather than a feeling.
This page starts from the fields where Riza genuinely trails the rosters it appears in, and only then covers the reasons that never show up in a table.

The measured reasons.

Snapshot & fork, No. Daytona records Yes.
Custom images, No. E2B records Yes.
Streaming output, No. E2B records Yes.
Max runtime, 1 min, the weakest of the 16 here. E2B records 1440 min.
Persistent FS, No. Modal records Yes.

Any one of those is enough on its own if you sized your architecture around it.
None of them is enough if you didn't, which is why the list is short and specific rather than a general case against Riza.

The reasons that never make it into a table.

A price rise after a funding round.
A licence change that turns a self-host into a subscription.
A region you now need and they do not have.
An acquisition.
A support experience that quietly degrades.
None of those are fields, and all of them move teams, which is why every entry below links back to Sandbox providers, where the full field set and its sources live.
The ones we catch get logged on the Riza timeline.

How the shortlist is ordered.

Every tool below shares at least one comparison category with Riza, sorted by how many categories the two overlap in.
There is no editorial ranking, no sponsorship and no affiliate link, the order is the overlap count.
The rationale under each is generated from the two tools' own cells, so it names real values rather than adjectives.

1.ascii

ascii, Agent orchestration over Telegram, running on box's VM infrastructure.
It meets Riza in Sandbox providers.
It is ahead on Root in guest (Yes against No), Snapshot & fork (Partial against No) and Custom images (Partial against No).
What you give up: Meter (subscription, where Riza records per-request).
Best for you want an agent you message rather than an API you call.
An agent harness with a VM attached, judged from an unverified vendor table with no fundamentals established.

Where ascii and Riza actually differ

Root in guest: YesRiza: No
Snapshot & fork: PartialRiza: No
Meter: subscriptionRiza: per-request
Custom images: PartialRiza: No
Preview URLs: PartialRiza: No

ascii profile Compare in Sandbox providers

2.Blaxel

Blaxel, Agent-first cloud claiming ~25 ms microVM boots from snapshots.
It meets Riza in Sandbox providers.
It is ahead on Snapshot & fork (Yes against No), Custom images (Yes against No) and Streaming output (Yes against No).
What you give up: Egress control (open, where Riza records blocked-by-default) and Idle cost (storage-only, where Riza records free-when-stopped).
Best for you want sandboxes, agent hosting and MCP from one vendor.
The 25 ms claim measures the wrong operation, and the broad platform is a lot to buy from a seed-stage company.

Where Blaxel and Riza actually differ

Snapshot & fork: YesRiza: No
Custom images: YesRiza: No
Streaming output: YesRiza: No
Max runtime: 1440minRiza: 1 min
Preview URLs: YesRiza: No
Root in guest: YesRiza: No

Blaxel profile Compare in Sandbox providers

3.box

box, Persistent Linux VMs with SSH, per-VM IPv4 and disk-level forking, priced flat.
It meets Riza in Sandbox providers.
It is ahead on Root in guest (Yes against No), Snapshot & fork (Partial against No) and Custom images (Partial against No).
What you give up: Meter (subscription, where Riza records per-request).
Best for you want a VM that stays up rather than a sandbox that vanishes.
A coherent long-lived-VM pitch, but a vendor self-assessment with no measured isolation, boot time or price.

Where box and Riza actually differ

Root in guest: YesRiza: No
Snapshot & fork: PartialRiza: No
Meter: subscriptionRiza: per-request
Custom images: PartialRiza: No
Preview URLs: PartialRiza: No

box profile Compare in Sandbox providers

4.Cloudflare Sandbox

Cloudflare Sandbox, Container sandboxes driven from a Worker, addressed through Durable Objects.
It meets Riza in Sandbox providers.
It is ahead on Custom images (Yes against No), Streaming output (Yes against No) and Preview URLs (Yes against No).
What you give up: Runtimes (any-oci-image, where Riza records python, javascript-typescript, ruby, php) and Isolation (container, where Riza records wasm).
Best for your app already runs on Workers and Durable Objects.
An addressable sandbox object in your app, worth it on Workers but too slow to migrate to.

Where Cloudflare Sandbox and Riza actually differ

Custom images: YesRiza: No
Streaming output: YesRiza: No
Preview URLs: YesRiza: No
Root in guest: YesRiza: No
Runtimes: any-oci-imageRiza: python, javascript-typescript, ruby, php
Funding: publicRiza: seed

Cloudflare Sandbox profile Compare in Sandbox providers

5.CodeSandbox SDK

CodeSandbox SDK, Firecracker VMs with memory snapshots, from the online IDE, now owned by Together AI.
It meets Riza in Sandbox providers.
It is ahead on Snapshot & fork (Yes against No), Custom images (Yes against No) and Streaming output (Yes against No).
What you give up: Egress control (open, where Riza records blocked-by-default) and MCP server (No, where Riza records Partial).
Best for you fork one prepared environment many times.
The best-engineered snapshot-and-fork here for branching workloads, now a component of Together AI rather than its own product.

Where CodeSandbox SDK and Riza actually differ

Snapshot & fork: YesRiza: No
Custom images: YesRiza: No
Streaming output: YesRiza: No
Max runtime: 1440minRiza: 1 min
Persistent FS: YesRiza: No
Preview URLs: YesRiza: No

CodeSandbox SDK profile Compare in Sandbox providers

6.Daytona

Daytona, Sub-second container sandboxes for agent workloads, from a team that built a dev-env manager.
It meets Riza in Sandbox providers.
It is ahead on Snapshot & fork (Yes against No), Custom images (Yes against No) and Streaming output (Yes against No).
What you give up: Isolation (container, where Riza records wasm) and Idle cost (storage-only, where Riza records free-when-stopped).
Best for boot time is your headline metric and the code is your own.
E2B's most credible ergonomics challenger with the best MCP story, but shared-kernel containers make it wrong for untrusted code.

Where Daytona and Riza actually differ

Snapshot & fork: YesRiza: No
Custom images: YesRiza: No
Streaming output: YesRiza: No
Max runtime: 1440minRiza: 1 min
Persistent FS: YesRiza: No
Preview URLs: YesRiza: No

Daytona profile Compare in Sandbox providers

7.Self-hosted Firecracker

Self-hosted Firecracker, The baseline: Firecracker on your own metal, plus every hard part you now own.
It meets Riza in Sandbox providers.
It is ahead on Custom images (Yes against No), Max runtime (1440 min against 1 min) and Persistent FS (Yes against No).
What you give up: Idle cost (full-rate, where Riza records free-when-stopped) and Meter (per-hour, where Riza records per-request).
Best for sustained volume where vendor margin exceeds an engineer's salary.
The honest baseline: identical isolation at a tenth the cost, minus the two engineer-years of orchestration.
Note that we carry Self-hosted Firecracker as the do-it-yourself baseline in that roster, the "what if we just ran this ourselves" reference point.
The honest answer is usually that it is cheaper and considerably more work.

Where Self-hosted Firecracker and Riza actually differ

Custom images: YesRiza: No
Idle cost: full-rateRiza: free-when-stopped
Max runtime: 1440minRiza: 1 min
Persistent FS: YesRiza: No
Root in guest: YesRiza: No
Sydney region: YesRiza: No

Self-hosted Firecracker profile Compare in Sandbox providers

8.E2B

E2B, Open-source Firecracker sandboxes with Python and TypeScript SDKs for AI agents.
It meets Riza in Sandbox providers.
It is ahead on Custom images (Yes against No), Streaming output (Yes against No) and Max runtime (1440 min against 1 min).
What you give up: Egress control (open, where Riza records blocked-by-default) and Idle cost (storage-only, where Riza records free-when-stopped).
Best for you want the category default with a real self-host escape hatch.
The safest default: complete SDKs, Dockerfile templates and an Apache licence, though no longer fastest and weak at hobby scale.

Where E2B and Riza actually differ

Custom images: YesRiza: No
Streaming output: YesRiza: No
Max runtime: 1440minRiza: 1 min
Preview URLs: YesRiza: No
Root in guest: YesRiza: No
Browser inside: YesRiza: No

E2B profile Compare in Sandbox providers

How this list was built

There is no editorial ranking on this page and no sponsorship behind it. The order is mechanical: every tool that shares a comparison category with Riza, sorted by how many categories the two overlap in. A tool that meets Riza in three rosters sits above one that meets it in a single roster, because more overlap means the comparison is more like-for-like.

The rationale under each entry is composed from the two tools' own cells. Where they differ on a field we score, the sentence names both values and the unit. Where they don't differ, it says so instead of manufacturing a distinction, which is why some entries are short.

Values, sources and verification dates all live on the category tables: Sandbox providers. If a figure here disagrees with a vendor's current pricing page, the vendor is right and we are stale.

Still deciding whether to move at all? The Riza profile has the when-to-use and when-not-to-use blocks, and the Riza timeline has the dated changes that usually trigger a migration.