Environment Variables

All environment variables recognized by Mimir and its components.

Application

MIMIR_DEV

Forces development mode regardless of build type. When set (any value), Mimir uses the dev database directory instead of production.

export MIMIR_DEV=1

Effect: Database and assets are read from {app_dir}/dev/data/ instead of {app_dir}/data/. This prevents development from modifying production campaign data.

Default: Not set. Dev mode is normally detected automatically via Rust’s cfg!(debug_assertions) — debug builds use dev paths, release builds use production paths.

RUST_LOG

Controls log verbosity using the tracing filter syntax.

# Show debug logs for all Mimir crates
export RUST_LOG=mimir=debug,mimir_core=debug

# Trace-level for the core crate only
export RUST_LOG=mimir_core=trace

# Quiet mode — errors only
export RUST_LOG=mimir=error

Default: mimir=info,mimir_core=info (all builds)

Log output: Written to files in the logs directory:

• macOS: ~/Library/Application Support/com.mimir.app/logs/
• Linux: ~/.local/share/com.mimir.app/logs/
• Windows: %APPDATA%/com.mimir.app/logs/

MCP Server

MIMIR_DATABASE_PATH

Overrides the database path for the MCP sidecar server. Useful when running the MCP server outside of Tauri (e.g., as a standalone process for Claude Code).

export MIMIR_DATABASE_PATH=~/Library/Application\ Support/com.mimir.app/data/mimir.db

Default: Platform-specific:

The path supports ~ and $HOME expansion.

Note on Linux: The MCP server respects the XDG_DATA_HOME environment variable. If unset, it falls back to ~/.local/share/.

MIMIR_SEED_ASSETS

Development only. Path to the seed-asset directory (sample UVTT maps, token images) used when seeding the dev database from the in-app Dev Tools.

export MIMIR_SEED_ASSETS=/path/to/mimir/crates/mimir-core/src/seed/assets

Default: Not set. The seeder walks parent directories looking for crates/mimir-core/src/seed/assets; the variable is only needed when running from a location where that walk fails.

Build System

TAURI_ENV_TARGET_TRIPLE

Set by Tauri during builds. Used by the sidecar build scripts to determine the target architecture.

# Set automatically by Tauri, but can be overridden for cross-compilation
export TAURI_ENV_TARGET_TRIPLE=aarch64-apple-darwin

Supported values:

• aarch64-apple-darwin (macOS ARM64)
• x86_64-apple-darwin (macOS Intel)
• x86_64-unknown-linux-gnu (Linux x86_64)
• aarch64-unknown-linux-gnu (Linux ARM64)
• x86_64-pc-windows-msvc (Windows x86_64)
• aarch64-pc-windows-msvc (Windows ARM64)

Default: Auto-detected from the current platform when not set.

CARGO_TERM_COLOR

Standard Cargo variable for controlling colored output. Set to always in CI workflows.

export CARGO_TERM_COLOR=always

Platform Directories

Mimir uses platform-appropriate directories following OS conventions. These aren’t environment variables, but they’re the default paths that environment variables override:

macOS

Linux

Windows

See Also

• Troubleshooting — Common issues related to paths and configuration
• Development Setup — Setting up a development environment
• MCP Server Reference — MCP server configuration