GitHub Copilot costs $19/month for individuals and $39/month per seat for businesses. Every keystroke gets sent to Microsoft's servers for processing. For enterprise teams working on proprietary code, that's a data governance problem. For independent developers, it's $228/year for a tool that sometimes suggests code from other people's repositories.
The alternative: open source AI coding assistants that let you choose your model, control where your code goes, and customize the tool to your workflow. Some of these connect to any LLM provider (including local models). Others build AI directly into the editor. All of them are free to use.
I compared 4 open source AI coding tools that can genuinely replace GitHub Copilot. Each takes a different approach — from IDE extensions to full editor replacements — so the right choice depends on how deep you want AI in your development workflow.
Key Takeaways:
- Best AI coding agent: Cline — autonomous Plan/Act modes with terminal access, browser automation, and MCP integration. Trusted by 5M+ developers
- Best for model flexibility: Continue — bring any model (local or API) into VS Code or JetBrains with custom AI assistants
- Best for enterprise: Cody — Sourcegraph's codebase-aware AI with enterprise security, audit logs, and multi-IDE support
- Best all-in-one editor: Zed — high-performance editor with built-in AI, multiplayer collaboration, and agentic editing
Quick Comparison
| Tool | Type | IDE Support | Model Choice | Self-Hosted Models | Agentic Capability |
|---|---|---|---|---|---|
| Cline | VS Code extension | VS Code | Any (multi-model) | Yes | Yes (Plan/Act) |
| Continue | IDE extension | VS Code, JetBrains | Any (fully configurable) | Yes | Partial |
| Cody | IDE extension | VS Code, JetBrains, Eclipse+ | Claude, GPT-4, Gemini | Enterprise option | Experimental |
| Zed | Full editor | Zed (standalone) | Built-in + configurable | Planned | Yes (agentic editing) |
What Makes a Good AI Coding Assistant
Before the detailed reviews, here's what separates useful AI coding tools from gimmicky ones:
- Context awareness — understanding your codebase, not just the current file
- Model flexibility — ability to use different models for different tasks (fast model for completion, powerful model for refactoring)
- Privacy control — choosing where your code gets sent (or keeping it local)
- Workflow integration — fitting into your existing IDE and habits, not replacing them
- Agentic capability — handling multi-step tasks (create file, edit code, run tests) autonomously
1. Cline — The Most Capable Open Source AI Coding Agent
Best for developers who want an AI that can plan, execute, test, and iterate on coding tasks autonomously.
Cline is the most powerful AI coding tool on this list. While other tools suggest code completions, Cline acts as a full coding agent. Its Plan/Act modes let you describe what you want, review the AI's plan, then let it execute — editing files, running terminal commands, and even automating browser testing. It's the closest thing to having a junior developer in your IDE.
Key Features
- Plan/Act modes — AI plans the approach, you review, then it executes autonomously
- Terminal command execution — runs build scripts, tests, and git commands directly
- File editing — creates, modifies, and deletes files based on task requirements
- Browser automation — tests web applications by controlling a browser
- Multi-model support — use Claude, GPT-4, Gemini, or local models per task
- MCP integration — connects to external tools and services via Model Context Protocol
- Real-time debugging — identifies issues and proposes fixes in context
Pros
- Most agentic capability of any open source coding tool — handles multi-step tasks end-to-end
- Plan/Act separation gives you oversight without micromanaging
- Multi-model support means you use the best model for each task
- MCP integration connects to databases, APIs, and external tools
- Trusted by 5M+ developers — large community and active development
Cons
- VS Code only — no JetBrains or other IDE support currently
- Agentic mode can run up API costs if not monitored
- Requires API keys for cloud models (or local model setup)
- Learning to write effective prompts takes practice
License and Setup
- License: Apache-2.0
- Install: VS Code Extension Marketplace
- Model setup: Bring your own API keys (Anthropic, OpenAI, Google) or connect to local models via Ollama
Pricing
- Extension: Free
- Model costs: Pay per API usage (varies by provider) or free with local models
Best For
Developers who want AI to handle multi-step coding tasks — not just autocomplete. If you describe features and want the AI to implement them (with your review), Cline's Plan/Act workflow is the most productive approach available.
View Cline on Open Source Alternatives
2. Continue — The Most Flexible Open Source AI Code Assistant
Best for developers who want total control over which AI models power their coding tools.
Continue is the Swiss Army knife of AI coding assistants. Where Copilot locks you into GitHub's model and pricing, Continue lets you plug in any model — Claude, GPT-4, Gemini, Llama, Mistral, or any model running locally via Ollama. You can configure different models for different tasks: a fast model for autocomplete, a powerful model for refactoring, a local model for sensitive code.
Key Features
- Flexible model integration — connect any LLM provider or local model
- Tab autocomplete — context-aware code completions as you type
- AI chat — ask questions about your codebase with file references
- Highlight and edit — select code, describe changes, and the AI rewrites it
- Custom AI assistants — create and share task-specific AI configurations
- VS Code and JetBrains support — works in both major IDE families
Pros
- Most model flexibility of any AI coding tool — use any model from any provider
- Custom assistants let teams standardize AI workflows across the codebase
- Self-hostable — run entirely on your infrastructure with local models
- Works in VS Code AND JetBrains — covers most developers' IDE choice
- Active open source development with regular releases
Cons
- Less agentic than Cline — good for completions and edits, not multi-step autonomous tasks
- Initial configuration takes more effort than Copilot's plug-and-play setup
- Quality depends heavily on which model you choose and how you configure it
- Documentation could be more comprehensive for advanced configurations
License and Setup
- License: Apache-2.0
- Install: VS Code or JetBrains extension marketplace
- Model setup: Configure via
config.json— supports 20+ model providers including Ollama for local
Pricing
- Extension: Free
- Model costs: Varies by provider (or free with local models like Llama, Mistral)
Best For
Developers and teams who want AI coding assistance without vendor lock-in. If you care about which model processes your code, want to use local models for sensitive projects, or need to customize AI behavior per project, Continue gives you complete control.
View Continue on Open Source Alternatives
3. Cody — Enterprise-Grade AI with Codebase Context
Best for engineering teams that need AI coding assistance with enterprise security, audit logging, and deep codebase understanding.
Cody comes from Sourcegraph, the company behind universal code search. Its key advantage: Cody understands your entire codebase, not just the open file. Sourcegraph's code intelligence indexes your repositories so Cody can answer questions about functions in other files, suggest changes that respect your coding patterns, and reference documentation from across your organization. For enterprise teams, the security features (data isolation, audit logs, admin controls) meet compliance requirements that Copilot's standard plan doesn't.
Key Features
- Codebase context — understands your entire repository structure, not just the current file
- AI chat — ask questions about your codebase and get context-aware answers
- Auto-edit — intelligent code completions that understand surrounding code
- Agentic chat (experimental) — multi-step coding assistance
- Inline edits — quick refactoring with natural language instructions
- Multi-IDE support — VS Code, Visual Studio, IntelliJ, Eclipse, and more
- Multiple LLM options — Claude, GPT-4, Gemini with model selection per task
- Enterprise security — data isolation, audit logs, admin controls, SSO
Pros
- Best codebase awareness of any tool on this list — Sourcegraph's code intelligence is a real advantage
- Broadest IDE support — works in 6+ editors
- Enterprise security features meet compliance requirements
- Multiple model options without managing your own API keys
- Backed by Sourcegraph — well-funded, active development
Cons
- Open core model — some enterprise features require paid plans
- Codebase indexing requires Sourcegraph setup for full capability
- Less agentic than Cline for autonomous multi-step tasks
- Free tier has usage limits on premium models
License and Setup
- License: Open core (Apache-2.0 for the extension, commercial for enterprise features)
- Install: Extension marketplace for your IDE
- Model setup: Managed by Sourcegraph — no API keys needed for included models
Pricing
- Free tier: Available with usage limits
- Pro: $9/month for higher limits
- Enterprise: Custom pricing
Best For
Engineering teams at companies where code security, compliance, and codebase-wide intelligence matter. If your team works on large, complex codebases and needs AI that understands the full picture (not just one file), Cody's Sourcegraph integration is the differentiator.
View Cody on Open Source Alternatives
4. Zed — AI-Native Editor with Multiplayer Collaboration
Best for developers who want AI built into the editor itself, not bolted on as an extension.
Zed takes a different approach from the other tools on this list. Instead of adding AI to an existing editor via extensions, Zed builds AI directly into a new, high-performance editor. Created by the team behind Atom and Tree-sitter, Zed is fast — benchmarks show it rendering faster than any Electron-based editor. The AI features include agentic editing (AI executes multi-step code changes), completions, and chat, all alongside real-time multiplayer collaboration.
Key Features
- Agentic editing — AI executes multi-step code changes within the editor
- AI-powered completions with edit prediction
- Real-time multiplayer collaboration — pair program with low-latency shared editing
- Native Git integration — stage, commit, and diff without leaving the editor
- Multi-language support via Tree-sitter and Language Server Protocol
- Remote development — connect to remote machines for development
- Jupyter runtime support — interactive programming with notebook-style execution
- Vim keybindings and modal editing support
- High performance — GPU-accelerated rendering, faster than VS Code
Pros
- Fastest editor on this list — noticeably faster than VS Code for large files
- AI and collaboration are native, not extensions — tighter integration
- Multiplayer editing is the best implementation in any code editor
- Built by the Atom/Tree-sitter team — deep editor expertise
- Growing extension ecosystem
Cons
- Standalone editor — you leave VS Code/JetBrains ecosystem and extensions
- Extension ecosystem is still growing (smaller than VS Code's)
- Newer project — some features are still maturing
- macOS and Linux only (Windows support in development)
License and Setup
- License: Open source (GPL-3.0 for the editor, Apache-2.0 for GPUI framework)
- Install: Direct download from zed.dev, or Homebrew on macOS
- AI setup: Built-in AI features, or configure custom model providers
Pricing
Free. Open source with optional Zed cloud features.
Best For
Developers ready to switch editors for a faster, AI-native experience. If VS Code feels slow, you want built-in pair programming, and you're willing to adapt to a newer extension ecosystem, Zed is the most forward-looking choice.
View Zed on Open Source Alternatives
How to Choose the Right AI Coding Assistant
If you want the most autonomous AI agent: Cline — its Plan/Act modes handle multi-step tasks end-to-end. Best for developers who describe what they want and review the output.
If you want maximum model flexibility: Continue — plug in any model, customize per project, and self-host for privacy. Best for teams that need control over their AI stack.
If you need enterprise security: Cody — Sourcegraph's codebase intelligence plus enterprise audit logs, SSO, and data isolation. Best for companies with compliance requirements.
If you want the fastest AI-native editor: Zed — purpose-built editor with AI and collaboration at its core. Best for developers willing to switch from VS Code for better performance.
Can you use multiple tools? Yes. Many developers use Continue or Cody for completions and chat, alongside Cline for agentic tasks. The tools are complementary, not exclusive.
Frequently Asked Questions
Can open source AI coding assistants really replace GitHub Copilot?
For most developers, yes. Cline and Continue both provide completions, chat, and code edits comparable to Copilot — often better, because you can use more capable models (Claude 3.5 Sonnet, GPT-4) instead of Copilot's default model. The gap: Copilot's tight GitHub integration (PR descriptions, commit messages) is more seamless. But the core coding assistance — completions, refactoring, explanation — is matched or exceeded.
Which tool is best for keeping code private?
Continue with local models (via Ollama) is the most private option — your code never leaves your machine. Cline also supports local models. Cody offers enterprise data isolation. Zed allows configuring custom endpoints. If privacy is non-negotiable, run Llama or Mistral locally through Continue or Cline — zero data transmission to any third party.
Do I need to pay for AI models to use these tools?
You can use them entirely free with local models. Install Ollama, download Llama 3 or Codestral, and connect it to Continue or Cline. Quality is lower than Claude or GPT-4 but improving rapidly. For production use, most developers pay $10-20/month for API access to a premium model — still cheaper than Copilot's $19/month with more model choice.
Which tool has the best code completions?
For pure autocomplete speed and accuracy, Continue and Cody are the strongest — both are optimized for real-time completions. Cline is better for longer code generation than quick completions. Zed's built-in completions are fast but the model options are more limited. The best completions come from pairing Continue or Cody with a fast model like Claude 3.5 Haiku or GPT-4 Mini.
Can these tools understand my entire codebase?
Cody has the best codebase understanding — Sourcegraph's code intelligence indexes your entire repository. Cline can access files and directories within your project. Continue provides context from open files and referenced code. Zed offers project-wide context through its AI features. For large monorepos (100K+ files), Cody's Sourcegraph integration is the only tool that provides true codebase-wide intelligence.
Do these work with languages other than JavaScript/Python?
Yes. All four tools support any language that has an LSP (Language Server Protocol) implementation — which covers virtually every programming language. Cline and Continue are language-agnostic since they work through LLM APIs. Cody supports all languages through Sourcegraph's multi-language indexing. Zed has Tree-sitter parsers for 50+ languages.
Are local AI models good enough for coding?
Getting there. Code Llama 34B and Codestral handle completions and simple refactoring well. For complex reasoning (architecture decisions, debugging subtle bugs), cloud models like Claude 3.5 Sonnet are still noticeably better. The practical approach: use local models for completions (fast, free, private) and cloud models for complex tasks (better quality, pay per use).
How do these compare to Cursor?
Cursor is a proprietary fork of VS Code with built-in AI. It's good but not open source — you can't self-host, audit the code, or control which models are used. Zed is the closest open source alternative (full editor with AI). Continue and Cline give you similar AI capabilities inside VS Code without switching editors. Cursor's advantage: tighter integration. Open source advantage: model choice, privacy, and no subscription lock-in.
Is it safe to use AI coding assistants on proprietary code?
With the right setup. Continue and Cline with local models = no data transmission. Cody Enterprise provides data isolation and audit logs for compliance. Avoid sending proprietary code to free-tier cloud APIs without reviewing the provider's data retention policy. Most enterprise API plans (Anthropic, OpenAI) don't train on your data, but verify the terms for your specific plan.
Which tool should a team of 10 developers adopt?
For a team, I'd recommend Continue for daily coding (model flexibility, both IDE families, self-hostable) combined with Cline for complex tasks (agentic capability). If your company has compliance requirements, Cody Enterprise is the safest choice with its audit logging and admin controls. Start with a 2-week trial — most developers know within a week whether an AI tool fits their workflow.
Last updated: April 2026. I review and update this article quarterly as AI coding tools evolve rapidly. Found an open source AI coding tool we should include? Submit it to our directory.