Spinup vs E2B
E2B's primitive is the secure code execution sandbox. Spinup is the agent runtime above the sandbox: one durable agent, one computer, any harness. E2B runs code. Spinup runs an agent that has its own workspace-owned identity, environment, harness, state, lifecycle, and recorded run history, with the sandbox handled underneath.
Where They Overlap
Both provide isolated execution for AI workloads
Spinup and E2B share a core belief: AI agents need real, isolated environments to operate in, not just model API calls.
Isolated execution environments
Both give agents sandboxed environments where code runs in isolation from the host and from other tenants. The agent gets a filesystem, shell, and network boundary. Your code and your customers' code never share a process space.
No infrastructure to manage
Neither requires teams to provision raw infrastructure to get an agent running. Both abstract over the underlying machine so the agent starts work without bespoke ops setup.
Where They Diverge
Different layers of the stack, different responsibilities
E2B owns the sandbox. Spinup owns the runtime above the sandbox. That one-layer difference changes what you build and what you get for free.
Agent model
Spinup treats the agent as a first-class runtime object with identity, lifecycle, and configuration. E2B provides sandboxes as execution primitives that your application code manages directly. With E2B, you define agent semantics in your own code. With Spinup, the runtime handles them.
Persistence and lifecycle
Spinup environments persist across runs with agent-scoped state. E2B sandboxes are ephemeral by default, with pause and resume available for preserving state between sessions. The defaults reflect different bets: Spinup starts from persistence, E2B starts from fast execution.
Harness portability
In Spinup, harnesses are swappable runtime components. Switch an agent from OpenClaw to Hermes today without reconfiguring its secrets, skills, or environment. Claude Code, Codex CLI, and other harnesses sit on the roadmap and will land on the same runtime shape. E2B does not include a harness management layer. Tooling choices stay in your application code.
Workspace and governance
Spinup includes workspace-level controls: audit logging, secrets management, and membership policy that govern how agents operate across a team. E2B is infrastructure-focused and leaves governance to the consuming application.
Side-by-Side
Spinup vs E2B at a glance
| Spinup | E2B | |
|---|---|---|
| What you manage | Agents: identity, environment, harness, and lifecycle bound together | Sandboxes: isolated environments for code execution |
| State between runs | Persistent by default. Agent state survives between sessions. | Ephemeral by default. Pause/resume available for persistence. |
| Switching harnesses | Swap harnesses per agent. Secrets, skills, and config stay stable. | Bring your own tooling. Harness changes are your responsibility. |
| Skills and secrets | Managed at the agent level: skills, secrets projection, configuration | Not managed at the sandbox layer |
| Persistence model | Per-agent persistent environment: files, packages, artifacts, and harness config carry between runs | Sandbox templates for pre-configured images |
| Isolation | MicroVM-backed environments per agent | Sandboxed execution environments |
| Team controls | Workspace membership, audit logging, secrets management | API key-based access |
| Best fit | Long-lived agents that persist state, swap harnesses, and operate under workspace policy | Fast ephemeral code execution, code interpreters, one-shot scripts |
The Layer Distinction
Runtime vs execution sandbox
E2B is a well-regarded, open-source sandbox for AI-native code execution. Developers building code interpreters, AI-generated code runners, and browser automation tools use it because it solves a clear problem: run this code safely and return the output.
Spinup operates one layer up. Instead of owning the sandbox primitive, Spinup owns the runtime above it: agent identity, environment persistence, harness management, secrets projection, and workspace-level governance. The sandbox runs the code. The runtime decides which agent runs, what it can access, and how its environment survives between sessions. The agent is the durable object. The active machine is replaceable capacity.
That layer distinction matters because teams building agent products eventually need both. They start with execution, then add persistence, then secrets, then harness portability, then audit logging. Each of those is a layer of infrastructure you either build yourself or get from a runtime. E2B gives you the first layer. Spinup gives you the rest.
When the workload is ephemeral (a code interpreter session, a one-shot script), E2B keeps things simple and avoids runtime overhead. When the workload behaves more like a long-lived agent that persists state, swaps harnesses, and operates under workspace policy, the runtime layer becomes necessary. That is the layer Spinup builds.
When to Choose
Different problems, different tools
Neither product is universally better. The question is whether you need an execution sandbox or an agent runtime.
Choose Spinup when
Your agents persist state between runs, swap harnesses without reconfiguration, and need agent-level secrets and skills. You want the runtime to manage agent lifecycle so your application code does not have to.
Choose Spinup when
Your team needs audit logging, secrets management, and membership controls that govern agent operations across the workspace. API key access is not enough.
Choose E2B when
The workload is ephemeral code execution: AI-generated scripts, code interpreter sessions, or short-lived computations where startup speed and simplicity matter most.
Choose E2B when
You want open-source execution primitives that you integrate directly into your application. You prefer building agent semantics in your own code rather than adopting an opinionated runtime.
FAQ
Spinup vs E2B questions
What is the main difference between Spinup and E2B?+
E2B gives you cloud sandboxes for running AI-generated code. Spinup gives you the layer above: a control plane that manages the agent, persistent environments, which harness is running, and secrets. E2B is the execution primitive. Spinup is the layer above it that decides what the agent can access, how its environment persists, and how it operates under workspace policy.
Is Spinup an E2B alternative?+
Not directly. E2B is infrastructure for executing code in sandboxes. Spinup is a runtime for managing agents that need persistent environments, swappable harnesses, and lifecycle controls. The real question is whether you need a sandbox or a runtime, because the answer determines how much agent infrastructure you build and maintain yourself.
Can I use E2B and Spinup together?+
In principle, yes. Spinup separates the agent model from the underlying isolation primitive. A future integration could delegate execution to E2B sandboxes, containers, microVMs, or other backends depending on the workload. No integration exists today, but the architecture is designed to allow it.
When should I choose E2B over Spinup?+
When the workload is closer to running a code snippet than operating a long-lived agent. Code interpreter sessions, short-lived computations, and one-shot script execution are where E2B keeps things simple. If you do not need persistent state, agent-level lifecycle management, or the ability to swap harnesses without rebuilding the setup, E2B avoids the overhead of a full runtime layer.
Learn More
Understand the runtime layer
These pages explain the concepts behind Spinup's approach to agent runtime and how it differs from sandbox infrastructure.
Early access
See what the runtime layer handles before you build it yourself.
Request access if this is the runtime shape your team has been missing.