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Comparison

How Moltis compares to other open-source AI agent frameworks.

Disclaimer: This comparison reflects publicly available information at the time of writing. Projects evolve quickly — check each project’s repository for the latest details. Contributions to keep this page accurate are welcome.

At a Glance

OpenClawPicoClawNanoClawZeroClawMoltis
LanguageTypeScriptGoTypeScriptRustRust
Agent loop~430K LoCSmall~500 LoC~3.4K LoC~5K LoC
Full codebase1,000+ tests~124K LoC (2,300+ tests)
RuntimeNode.js + npmSingle binaryNode.jsSingle binary (3.4 MB)Single binary (44 MB)
SandboxApp-levelDockerDockerDocker + Apple Container
Memory safetyGCGCGCOwnershipOwnership, zero unsafe*
AuthBasicAPI keysNoneToken + OAuthPassword + Passkey + API keys
Voice I/OPluginBuilt-in (15+ providers)
MCPYesYes (stdio + HTTP/SSE)
HooksYes (limited)15 event types
SkillsYes (store)YesYesYesYes (+ OpenClaw Store)
Memory/RAGPluginPer-groupSQLite + FTSSQLite + FTS + vector

* unsafe is denied workspace-wide in Moltis. The only exceptions are opt-in FFI wrappers behind the local-embeddings feature flag, not part of the core.

Architecture Approach

OpenClaw is the original and most popular project (~211K stars). It ships as a Node.js application with 52+ modules, 45+ npm dependencies, and a large surface area. It has the richest ecosystem of third-party skills and integrations, but the codebase is difficult to audit end-to-end.

PicoClaw — Minimal Go binary

PicoClaw targets extreme resource constraints — $10 SBCs, RISC-V boards, and devices with as little as 10 MB of RAM. It boots in under 1 second on 0.6 GHz hardware. The trade-off is a narrower feature set: no sandbox isolation, no built-in memory/RAG, and limited extensibility.

NanoClaw — Container-first TypeScript

NanoClaw strips away OpenClaw’s complexity to deliver a small, readable TypeScript codebase with first-class container isolation. Agents run in Linux containers with filesystem isolation. It uses Claude Agent SDK for sub-agent delegation and per-group CLAUDE.md memory files. The trade-off is Node.js as a runtime dependency and a smaller feature surface.

ZeroClaw — Lightweight Rust

ZeroClaw compiles to a tiny 3.4 MB binary with <5 MB RAM usage and sub-10ms startup. It uses trait-driven architecture with 22+ provider implementations and 9+ channel integrations. Memory is backed by SQLite with hybrid vector + FTS search. The focus is on minimal footprint and broad platform support.

Moltis — Auditable Rust gateway

Moltis prioritizes auditability and defense in depth. The core agent engine (runner + provider model) is ~5K lines; the core (excluding the optional web UI) is ~121K lines across modular crates, each independently auditable. Key differences from ZeroClaw:

  • Larger binary (44 MB) in exchange for built-in voice I/O, browser automation, web UI, and MCP support
  • Apple Container support in addition to Docker
  • WebAuthn passkey authentication — not just tokens
  • 15 lifecycle hook events with circuit breaker and dry-run mode
  • Built-in web UI with real-time streaming, settings management, and session branching

Security Model

AspectOpenClawPicoClawNanoClawZeroClawMoltis
Code sandboxApp-level permissionsNoneDocker containersDocker containersDocker + Apple Container
Secret handlingEnvironment variablesEnvironment variablesEnvironment variablesEncrypted profilessecrecy::Secret, zeroed on drop
Auth methodBasic passwordAPI keys onlyNone (WhatsApp auth)Token + OAuthPassword + Passkey + API keys
SSRF protectionPluginDNS validationDNS-resolved, blocks loopback/private/link-local/CGNAT
WebSocket originN/ACross-origin rejection
unsafe codeN/A (JS)N/A (Go)N/A (JS)MinimalDenied workspace-wide*
Hook gatingSkills-basedBeforeToolCall inspect/modify/block
Rate limitingPer-IP throttle, strict login limits

Performance

MetricOpenClawPicoClawZeroClawMoltis
Binary / dist size~28 MB (node_modules)<10 MB3.4 MB44 MB
Cold start>30s<1s<10ms~1s
RAM (idle)>100 MB<10 MB<5 MB~30 MB
Min hardwareModern desktop$10 SBC (RISC-V)$10 SBCRaspberry Pi 4+

Moltis is larger because it bundles a web UI, voice engine, browser automation, and MCP runtime. Use --no-default-features --features lightweight for constrained devices.

When to Choose What

Choose OpenClaw if you want the largest ecosystem, maximum third-party skills, and don’t mind Node.js as a dependency.

Choose PicoClaw if you need to run on extremely constrained hardware ($10 boards, RISC-V) and can accept a minimal feature set.

Choose NanoClaw if you want a small, readable TypeScript codebase with container isolation and don’t need voice, MCP, or a web UI.

Choose ZeroClaw if you want the smallest possible Rust binary, sub-10ms startup, and broad channel support without a web UI.

Choose Moltis if you want:

  • A single auditable Rust binary with built-in web UI
  • Voice I/O with 15+ providers (8 TTS + 7 STT)
  • MCP server support (stdio + HTTP/SSE)
  • WebAuthn passkey authentication
  • Apple Container sandbox support (macOS native)
  • 15 lifecycle hook events with circuit breaker
  • Embeddings-powered long-term memory with hybrid search
  • Cron scheduling, browser automation, and Tailscale integration