deepseek-harness vs langchain

The two are close in size: 223.4k stars for deepseek-harness, 146.3k for langchain. Over the days we have tracked them deepseek-harness moved +109.9% and langchain +3.1%, so deepseek-harness is growing faster right now.

They split the axes: deepseek-harness leads on customization, langchain on model freedom.

Stars and commit dates come from our own daily tracking. The six axes are read off each project's documentation by our review pipeline, so they describe what a project says about itself, not what we measured in its code.

Where they stand today

A plugin-first agent harness where every component is a plugin, enabling highly composable agent workflows.

Stars
223.4k
Tracked growth
+109.9%
Maturity
Last commit
3d ago
Language
TypeScript
License
MIT
Cost to run
Free, self-hosted

A broad, production-ready agent framework with a large ecosystem of integrations and modular abstractions to swap models, tools, and retrievers without rewriting application code.

Stars
146.3k
Tracked growth
+3.1%
Maturity
Last commit
2h ago
Language
Python
License
MIT
Cost to run
Your API key, per-provider pricing
0%+110%61 tracked days
deepseek-ai/deepseek-harnesslangchain-ai/langchain

Six axes, head to head

Each axis runs 0 to 5. The label under a score is what that project's own docs claim, not a category average.

Axisdeepseek-harnesslangchain
Context depth
How much of your codebase it sees before it answers: the open diff, the diff plus related files, or the whole repository.
Diff only
Diff/file only
Noise control
How it keeps output volume down — severity thresholds, deduplication, incremental runs over new commits only.
No controls
None mentioned
Customization
How far it bends to your team: custom rules, prompts, style guides, per-path config.
Plugin-based
Config & prompts
Privacy
Whether your code stays on your own infrastructure: fully local, self-hostable, or cloud API only.
Self-hostable
Cloud-key usage
Model freedom
Whether you can point it at any provider, or it is wired to one.
Fixed provider only
Multiple providers
Setup ease
What it takes to get a first useful run out of it.
One-command start
One-command start

Which one to pick

Pick deepseek-harness if…

Extensible plugin architecture — pick this when you want a locally runnable, highly modular agent harness you can extend with custom plugins.

  • Customization: Plugin-based (5/5 against 3/5)
Runs in cli, web-app. Works with other-fixed.

Pick langchain if…

Model interoperability — Swap providers and integrations easily to prototype and productionize LLM applications with minimal code changes.

  • Model freedom: Multiple providers (3/5 against 1/5)
Runs in cli, ide, ci, web-app. Works with byok, openai, anthropic, gemini.

What people want from each one

Questions people ask

Is deepseek-harness better than langchain?

They split the axes: deepseek-harness leads on customization, langchain on model freedom. deepseek-harness is worth picking when extensible plugin architecture — pick this when you want a locally runnable, highly modular agent harness you can extend with custom plugins.

Which of deepseek-harness and langchain keeps my code private?

deepseek-harness: Self-hostable (4/5). langchain: Cloud-key usage (3/5).

What does each one cost to run?

deepseek-harness: Free, self-hosted. langchain: Your API key, per-provider pricing.

Full profiles: deepseek-ai/deepseek-harness and langchain-ai/langchain. Everything else in Agent SDKs & frameworks.