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Alternatives · Memory & Evals

OpenViking alternatives (2026)

OpenViking: AGPL-3.0 self-evolving context DB. Broad memory/RAG/skills surface; network copyleft is a deployment decision, not a footnote.

Its Catch: AGPL-3.0 is strong copyleft, including the network-copyleft boundary when you modify OpenViking and offer it as a service.

Below: 8 free or free-tier tools from the same category (agent memory tools), free and open source first, then the closest match by shared tags. Each keeps its own Catch.

  1. 1.Mem0Memory infrastructure for AI agents that actually persists

    Free / OSS · Freemium · 67.4k GitHub stars

    VerdictThe memory layer most agent teams should use instead of building.

    CatchExternal dependency for a core capability. Async processing adds latency. Platform optimizations are not in the open-source SDK. You are trusting Mem0 with potentially sensitive user data.

  2. 2.LettaEpisodic memory for agents that think across sessions

    Free / OSS · Apache-2.0 · 25.2k GitHub stars

    VerdictThe memory architecture for agents that need to think long-term.

    CatchMore complex to reason about than simple vector retrieval. The paging mechanism adds latency and orchestration overhead. Documentation assumes understanding of the original MemGPT paper.

  3. 3.GraphitiApache-2.0 temporal knowledge graphs for agent memory; Zep's OSS engine

    Free / OSS · Apache-2.0 · 32k GitHub stars

    VerdictApache-2.0 temporal memory graphs. Free self-host; Zep Cloud is the paid path.

    CatchFramework only — you run a graph DB + ops. Zep Community Edition deprecated; full Zep SaaS is separate (Free credits then Flex ~$104/mo billed annually). Not a drop-in chat history store. Schema/ops cost vs Mem0 Docker.

  4. 4.EngramMIT persistent agent memory — MCP, CLI, TUI, SQLite

    Free / OSS · OSS/MIT · 7.4k GitHub stars

    VerdictMIT agent memory primitive. MCP/CLI/TUI on SQLite; not a full agent framework.

    CatchVs Mem0 / Letta / full agent frameworks: Engram is the memory primitive (store + retrieve + surfaces), not an orchestration framework or coding agent. “local or cloud” branding means optional hosted/sync gravity — day-one stays OSS you run. You still decide what gets written and when.

  5. 5.oh-my-hermesMIT Hermes-agent niche tooling — memory & workflows

    Free / OSS · OSS/MIT · 3.4k GitHub stars

    VerdictMIT Hermes-agent tooling. Niche, not a multi-host skill pack.

    CatchHermes-specific — not a generic Claude Code / Codex skill pack. Young surface; expect Hermes Agent as the host and follow upstream Hermes breaking changes. Vs ECC (multi-host ecosystem) and security-audit-skill (Cloudflare audit skill): oh-my-hermes is niche Hermes tooling, not a cross-harness coordination layer or a security scanner.

  6. 6.FridaySelf-hosted cognitive memory MCP for coding agents

    Free / OSS · OSS/MIT · 68 GitHub stars

    VerdictMIT self-hosted memory MCP. Use when coding agents need durable local memory without Mem0 Cloud.

    CatchVs Mem0 / Letta / Graphiti: Friday is the self-hosted MCP memory appliance for coding agents, not a multi-tenant memory API or a full agent OS. You operate Neo4j/Compose and embedding/model keys; star count is still early — pin and verify before production trust.

  7. 7.SupermemoryMIT memory/context engine with a local API

    Free / OSS · OSS/MIT · 31.3k GitHub stars

    VerdictMIT memory/context engine. Fast local/API path; verify the paid self-host boundary before planning a hosted deployment.

    CatchVs Mem0 / Letta / Graphiti: Supermemory leans into a local/API speed angle, not the same graph-orchestration shape. pricing caveat: the pricing page gates self-hosted deployments to paid tiers while the README documents a free local binary — read “self-host” as the OSS/local path, not a promise that every production deployment tier is free. You still own data policy and retrieval quality.

  8. 8.OKF Agent MemoryGit-native dual-memory for agents — OKF v0.2 + embedded MCP

    Free / OSS · OSS/MIT · 824 GitHub stars

    VerdictMIT git-native agent memory. Use when you want OKF bundles and MCP retrieval without another database.

    CatchVs Engram / Mem0 / Supermemory / Letta: OKF is the git-native OKF+AAG dual-memory recipe with MCP, not a hosted memory SaaS or paging OS. You still author the Domain Codex and decide write discipline; empty knowledge/ stays empty.

FAQ

What are the best free alternatives to OpenViking?
Mem0, Letta, Graphiti, Engram, oh-my-hermes. All are reviewed on Stack Gems in the same category (agent memory tools); 8 free or open source.
What is the catch with OpenViking?
AGPL-3.0 is strong copyleft, including the network-copyleft boundary when you modify OpenViking and offer it as a service.
Is there an open-source alternative to OpenViking?
Yes: Mem0 (Freemium), Letta (Apache-2.0), Graphiti (Apache-2.0), Engram (OSS/MIT).

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