Claudium

The free build of Claude Code.

All telemetry stripped. All injected security-prompt guardrails removed. All experimental features unlocked. One binary, zero callbacks home.

curl -fsSL https://raw.githubusercontent.com/DdogezD/claudium/main/install.sh | bash

Checks your system, installs Bun if needed, clones, builds with all features enabled, and puts claudium on your PATH. See API Configuration for API setup.

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What is this

This is a clean, buildable fork of Anthropic's Claude Code CLI -- the terminal-native AI coding agent. The upstream source became publicly available on March 31, 2026 through a source map exposure in the npm distribution.

This fork applies four categories of changes on top of that snapshot:

1. Privacy-First

Eliminates all tracking and remote-control mechanisms present in the original Claude Code:

• No telemetry – No unnecessary data is transmitted to Anthropic servers
• No analytics – No usage tracking or event logging
• No fingerprinting – No user or environment identification
• No auto-updates – No remote version control or forced updates

2. OpenAI-compatible API support

Added an API shim layer (src/services/api/openaiShim.ts) transparently translates between Anthropic message format and OpenAI-compatible APIs. It supports both Chat Completions and the newer Responses API, so all Claude Code tools (bash, file read/write, grep, glob, agents, MCP, etc.) keep working while you swap in a different backend LLM.

3. Security-prompt guardrails removed

Anthropic injects system-level instructions into every conversation that constrain Claude's behavior beyond what the model itself enforces. These include:

• Hardcoded refusal patterns for certain categories of prompts
• Injected "cyber risk" instruction blocks
• Managed-settings security overlays pushed from Anthropic's servers

This build strips those injections. The model's own safety training still applies —— this just removes the extra layer of prompt-level restrictions that the CLI wraps around it.

4. Experimental features enabled

Claude Code ships with dozens of feature flags gated behind bun:bundle compile-time switches. Most are disabled in the public npm release. This build unlocks all 45+ flags that compile cleanly, including:

Feature	What it does
ULTRAPLAN	Remote multi-agent planning on Claude Code web (Opus-class)
ULTRATHINK	Deep thinking mode -- type "ultrathink" to boost reasoning effort
VOICE_MODE	Push-to-talk voice input and dictation
AGENT_TRIGGERS	Local cron/trigger tools for background automation
BRIDGE_MODE	IDE remote-control bridge (VS Code, JetBrains)
TOKEN_BUDGET	Token budget tracking and usage warnings
BUILTIN_EXPLORE_PLAN_AGENTS	Built-in explore/plan agent presets
VERIFICATION_AGENT	Verification agent for task validation
BASH_CLASSIFIER	Classifier-assisted bash permission decisions
EXTRACT_MEMORIES	Post-query automatic memory extraction
HISTORY_PICKER	Interactive prompt history picker
MESSAGE_ACTIONS	Message action entrypoints in the UI
QUICK_SEARCH	Prompt quick-search
SHOT_STATS	Shot-distribution stats
COMPACTION_REMINDERS	Smart reminders around context compaction
CACHED_MICROCOMPACT	Cached microcompact state through query flows

See FEATURES.md for the full audit of all 88 flags and their status.

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Quick install

curl -fsSL https://raw.githubusercontent.com/DdogezD/claudium/main/install.sh | bash

This will check your system, install Bun if needed, clone the repo, build the binary cli-dev (with all experimental features enabled), and put it as claudium on your PATH.

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Requirements

• Bun >= 1.3.11
• macOS or Linux (Windows via WSL)
• An API key (Anthropic Messages or OpenAI-compatible APIs)

# Install Bun if you don't have it
curl -fsSL https://bun.sh/install | bash

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Build

# Clone the repo
git clone https://github.com/DdogezD/claudium.git
cd claudium

# Install dependencies
bun install

# Standard build -- produces ./cli
bun run build

# Dev build -- dev version stamp, experimental GrowthBook key
bun run build:dev

# Dev build with ALL experimental features enabled -- produces ./cli-dev
bun run build:dev:full

# Compiled build (alternative output path) -- produces ./dist/cli
bun run compile

Build variants

Command	Output	Features	Notes
bun run build	./cli	VOICE_MODE only	Production-like binary
bun run build:dev	./cli-dev	VOICE_MODE only	Dev version stamp
bun run build:dev:full	./cli-dev	All 45+ experimental flags	The full unlock build
bun run compile	./dist/cli	VOICE_MODE only	Alternative output directory

Individual feature flags

You can enable specific flags without the full bundle:

# Enable just ultraplan and ultrathink
bun run ./scripts/build.ts --feature=ULTRAPLAN --feature=ULTRATHINK

# Enable a specific flag on top of the dev build
bun run ./scripts/build.ts --dev --feature=BRIDGE_MODE

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Run

# Run the installed binary
claudium

# Or the built binary
./cli

# Or the dev binary
./cli-dev

# Or run from source without compiling (slower startup)
bun run dev

# See [API Configuration](#api-configuration) for API setup.

# Or use Claude.ai OAuth
claudium /login

Quick test

# One-shot mode
claudium -p "what files are in this directory?"

# Interactive REPL (default)
claudium

# With specific model
claudium --model claude-sonnet-4-6-20250514

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Project structure

scripts/
  build.ts              # Build script with feature flag system

src/
  entrypoints/cli.tsx   # CLI entrypoint
  commands.ts           # Command registry (slash commands)
  tools.ts              # Tool registry (agent tools)
  QueryEngine.ts        # LLM query engine
  screens/REPL.tsx      # Main interactive UI

  commands/             # /slash command implementations
  tools/                # Agent tool implementations (Bash, Read, Edit, etc.)
  components/           # Ink/React terminal UI components
  hooks/                # React hooks
  services/             # API client, MCP, OAuth, analytics
  state/                # App state store
  utils/                # Utilities
  skills/               # Skill system
  plugins/              # Plugin system
  bridge/               # IDE bridge
  voice/                # Voice input
  tasks/                # Background task management

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Tech stack

Runtime	Bun
Language	TypeScript
Terminal UI	React + Ink
CLI parsing	Commander.js
Schema validation	Zod v4
Code search	ripgrep (bundled)
Protocols	MCP, LSP
API	Anthropic Messages API / OpenAI-compatible APIs

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API Configuration

Claudium supports both Anthropic Messages API (natively) and OpenAI-compatible APIs. The shim can use either Chat Completions or the newer Responses API depending on the provider and model you configure.

Anthropic Messages API

Use the official Anthropic Messages API with your Anthropic API key.

export ANTHROPIC_API_KEY="sk-ant-..."

OpenAI-compatible APIs

Enable OpenAI-compatible mode and configure your preferred provider:

export CLAUDE_CODE_USE_OPENAI=1

Environment Variables

Variable	Description
OPENAI_API_KEY	API key (required for cloud APIs, optional for local models)
OPENAI_BASE_URL	API base URL (default: https://api.openai.com/v1)
OPENAI_MODEL	Model ID (default: gpt-4o)
OPENAI_API_MODE	Force transport selection: chat_completions or responses
ANTHROPIC_DEFAULT_OPUS_MODEL	Override which concrete model the opus alias resolves to
ANTHROPIC_DEFAULT_SONNET_MODEL	Override which concrete model the sonnet alias resolves to
ANTHROPIC_DEFAULT_HAIKU_MODEL	Override which concrete model the haiku alias resolves to
CLAUDE_CODE_MAX_CONTEXT_TOKENS	Override max context window size
CLAUDE_CODE_SUMMARY_OUTPUT_TOKENS	Override token limit for summarized context
CLAUDE_CODE_AUTO_COMPACT_BUFFER_TOKENS	Override auto-compact buffer size

Autocompact buffer = CLAUDE_CODE_SUMMARY_OUTPUT_TOKENS + CLAUDE_CODE_AUTO_COMPACT_BUFFER_TOKENS

Use OPENAI_MODEL when you want to pin the whole session to one exact model. Use ANTHROPIC_DEFAULT_OPUS_MODEL, ANTHROPIC_DEFAULT_SONNET_MODEL, and ANTHROPIC_DEFAULT_HAIKU_MODEL when you want aliases such as opus, sonnet, and haiku to resolve to your own provider-specific model IDs.

Transport selection

• Codex aliases such as codexplan and codexspark also use the unified Responses transport, but through the ChatGPT Codex auth/backend path.
• Other OpenAI-compatible backends stay on Chat Completions by default for maximum compatibility unless you explicitly select Responses.
• Official OpenAI requests that include reasoning still use the Responses API.
• Set OPENAI_API_MODE=responses to force /responses on providers that support it, or OPENAI_API_MODE=chat_completions to force the legacy path.

Provider Examples

OpenAI (Responses API, explicit):

export CLAUDE_CODE_USE_OPENAI=1
export OPENAI_API_KEY=sk-...
export OPENAI_MODEL=gpt-5.4
export OPENAI_API_MODE=responses

**OpenAI ChatGPT **

export CLAUDE_CODE_USE_OPENAI=1
export OPENAI_API_KEY=sk-...
export OPENAI_MODEL=gpt-4o
export OPENAI_API_MODE=chat_completions

OpenAI ChatGPT Codex:

export CLAUDE_CODE_USE_OPENAI=1
export CODEX_API_KEY=eyJ...
export CHATGPT_ACCOUNT_ID=account_...
export OPENAI_MODEL=codexplan

OpenRouter:

export CLAUDE_CODE_USE_OPENAI=1
export OPENAI_API_KEY=sk-or-v1-...
export OPENAI_BASE_URL=https://openrouter.ai/api/v1
export OPENAI_MODEL=openai/gpt-5.4

DeepSeek:

export CLAUDE_CODE_USE_OPENAI=1
export OPENAI_API_KEY=sk-...
export OPENAI_BASE_URL=https://api.deepseek.com/v1
export OPENAI_MODEL=deepseek-chat

LLaMA.CPP (local):

export CLAUDE_CODE_USE_OPENAI=1
export OPENAI_BASE_URL=http://localhost:1234/v1
export OPENAI_MODEL=your-model-name
export CLAUDE_CODE_MAX_CONTEXT_TOKENS=65536
export CLAUDE_CODE_SUMMARY_OUTPUT_TOKENS=12000
export CLAUDE_CODE_AUTO_COMPACT_BUFFER_TOKENS=4000

Ollama (local):

export CLAUDE_CODE_USE_OPENAI=1
export OPENAI_BASE_URL=http://localhost:1234/v1
export OPENAI_MODEL=llama3.3

LM Studio (local):

export CLAUDE_CODE_USE_OPENAI=1
export OPENAI_BASE_URL=http://localhost:1234/v1
export OPENAI_MODEL=your-model-name

Azure OpenAI:

export CLAUDE_CODE_USE_OPENAI=1
export OPENAI_API_KEY=your-azure-key
export OPENAI_BASE_URL=https://your-resource.openai.azure.com/openai/deployments/your-deployment
export OPENAI_MODEL=gpt-4o
export AZURE_OPENAI_API_VERSION=2024-12-01-preview

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License

The original Claude Code source is the property of Anthropic. This fork exists because the source was publicly exposed through their npm distribution. Use at your own discretion.