Use mise [env] as centralized configuration with backward-compatible defaults.
Core Principle
Define all configurable values in .mise.toml [env] section. Scripts read via environment variables with fallback defaults. Same code path works WITH or WITHOUT mise installed.
Key insight: mise auto-loads [env] values when shell has mise activate configured. Scripts using os.environ.get("VAR", "default") pattern work identically whether mise is present or not.
Quick Reference
Language Patterns
| Python
| os.environ.get("VAR", "default")
| Returns string, cast if int
| Bash
| ${VAR:-default}
| Standard POSIX expansion
| JavaScript
| process.env.VAR || "default"
| Falsy check, watch for "0"
| Go
| os.Getenv("VAR") with default
| Empty string if unset
| Rust
| std::env::var("VAR").unwrap_or()
| Returns Result
Special Directives
| _.file
| Load from .env files
| _.file = ".env"
| _.path
| Extend PATH
| _.path = ["bin", "node_modules/.bin"]
| _.source
| Execute bash scripts
| _.source = "./scripts/env.sh"
| _.python.venv
| Auto-create Python venv
| _.python.venv = { path = ".venv", create = true }
Python Venv Auto-Creation (Critical)
Auto-create and activate Python virtual environments:
[env]
_.python.venv = { path = ".venv", create = true }
This pattern is used in ALL projects. When entering the directory with mise activated:
-
Creates
.venvif it doesn't exist -
Activates the venv automatically
-
Works with
uvfor fast venv creation
Alternative via [settings]:
[settings]
python.uv_venv_auto = true
Monorepo Workspace Pattern
For Python monorepos using uv workspaces, the venv is created at the workspace root. Sub-packages share the root venv.
# Root mise.toml
[env]
_.python.venv = { path = ".venv", create = true }
Hoisted Dev Dependencies (PEP 735)
Dev dependencies (pytest, ruff, jupyterlab, etc.) should be hoisted to workspace root pyproject.toml using [dependency-groups]:
# SSoT-OK: example workspace configuration
# Root pyproject.toml
[tool.uv.workspace]
members = ["packages/*"]
[dependency-groups]
dev = [
"pytest>=<version>",
"ruff>=<version>",
"jupyterlab>=<version>",
]
Why hoist? Sub-package [dependency-groups] are NOT automatically installed by uv sync from root. Hoisting ensures:
-
Single command:
uv sync --group dev -
No "unnecessary package" warnings
-
Unified dev environment across all packages
Reference: bootstrap-monorepo.md for complete workspace setup
Special Directives
Load from .env Files (_.file)
[env]
# Single file
_.file = ".env"
# Multiple files with options
_.file = [
".env",
{ path = ".env.secrets", redact = true }
]
Extend PATH (_.path)
[env]
_.path = [
"{{config_root}}/bin",
"{{config_root}}/node_modules/.bin",
"scripts"
]
Source Bash Scripts (_.source)
[env]
_.source = "./scripts/env.sh"
_.source = { path = ".secrets.sh", redact = true }
Lazy Evaluation (tools = true)
By default, env vars resolve BEFORE tools install. Use tools = true to access tool-generated paths:
[env]
# Access PATH after tools are set up
GEM_BIN = { value = "{{env.GEM_HOME}}/bin", tools = true }
# Load .env files after tool setup
_.file = { path = ".env", tools = true }
Template Syntax (Tera)
mise uses Tera templating. Delimiters: {{ }} expressions, {% %} statements, {# #} comments.
Built-in Variables
| {{config_root}}
| Directory containing .mise.toml
| {{cwd}}
| Current working directory
| {{env.VAR}}
| Environment variable
| {{mise_bin}}
| Path to mise binary
| {{mise_pid}}
| mise process ID
| {{xdg_cache_home}}
| XDG cache directory
| {{xdg_config_home}}
| XDG config directory
| {{xdg_data_home}}
| XDG data directory
Functions
[env]
# Get env var with fallback
NODE_VER = "{{ get_env(name='NODE_VERSION', default='20') }}"
# Execute shell command
TIMESTAMP = "{{ exec(command='date +%Y-%m-%d') }}"
# System info
ARCH = "{{ arch() }}" # x64, arm64
OS = "{{ os() }}" # linux, macos, windows
CPUS = "{{ num_cpus() }}"
# File operations
VERSION = "{{ read_file(path='VERSION') | trim }}"
HASH = "{{ hash_file(path='config.json', len=8) }}"
Filters
[env]
# Case conversion
SNAKE = "{{ name | snakecase }}"
KEBAB = "{{ name | kebabcase }}"
CAMEL = "{{ name | lowercamelcase }}"
# String manipulation
TRIMMED = "{{ text | trim }}"
UPPER = "{{ text | upper }}"
REPLACED = "{{ text | replace(from='old', to='new') }}"
# Path operations
ABSOLUTE = "{{ path | absolute }}"
BASENAME = "{{ path | basename }}"
DIRNAME = "{{ path | dirname }}"
Conditionals
[env]
{% if env.DEBUG %}
LOG_LEVEL = "debug"
{% else %}
LOG_LEVEL = "info"
{% endif %}
Required & Redacted Variables
Required Variables
Enforce variable definition with helpful messages:
[env]
DATABASE_URL = { required = true }
API_KEY = { required = "Get from https://example.com/api-keys" }
Redacted Variables
Hide sensitive values from output:
[env]
SECRET = { value = "my_secret", redact = true }
_.file = { path = ".env.secrets", redact = true }
# Pattern-based redactions
redactions = ["*_TOKEN", "*_KEY", "PASSWORD"]
[settings] Section
[settings]
experimental = true # Enable experimental features
python.uv_venv_auto = true # Auto-create venv with uv
[tools] Version Pinning
Pin tool versions for reproducibility:
[tools]
python = "3.11" # minimum baseline; use 3.12, 3.13 as needed
node = "latest"
uv = "latest"
# With options
rust = { version = "1.75", profile = "minimal" }
min_version: Enforce mise version compatibility:
min_version = "2024.9.5"
Implementation Steps
-
Identify hardcoded values - timeouts, paths, thresholds, feature flags
-
Create
.mise.toml- add[env]section with documented variables -
Add venv auto-creation -
_.python.venv = { path = ".venv", create = true } -
Update scripts - use env vars with original values as defaults
-
Add ADR reference - comment:
# ADR: 2025-12-08-mise-env-centralized-config -
Test without mise - verify script works using defaults
-
Test with mise - verify activated shell uses
.mise.tomlvalues
GitHub Token Multi-Account Patterns (MANDATORY for Multi-Account Setups)
For multi-account GitHub setups, mise [env] provides per-directory token configuration that overrides gh CLI's global authentication.
Token Storage
Store tokens in a centralized, secure location:
mkdir -p ~/.claude/.secrets
chmod 700 ~/.claude/.secrets
# Create token files (one per account)
gh auth login # authenticate as account
gh auth token > ~/.claude/.secrets/gh-token-accountname
chmod 600 ~/.claude/.secrets/gh-token-*
Per-Directory Configuration
# ~/.claude/.mise.toml (terrylica account)
[env]
GH_TOKEN = "{{ read_file(path=config_root ~ '/.secrets/gh-token-terrylica') | trim }}"
GITHUB_TOKEN = "{{ read_file(path=config_root ~ '/.secrets/gh-token-terrylica') | trim }}"
GH_ACCOUNT = "terrylica" # For human reference only
# ~/eon/.mise.toml (terrylica account - different directory)
[env]
GH_TOKEN = "{{ read_file(path=env.HOME ~ '/.claude/.secrets/gh-token-terrylica') | trim }}"
GITHUB_TOKEN = "{{ read_file(path=env.HOME ~ '/.claude/.secrets/gh-token-terrylica') | trim }}"
GH_ACCOUNT = "terrylica"
Variable Naming Convention
| GH_TOKEN
| mise [env], Doppler, verification tasks
| .mise.toml, shell scripts
| GITHUB_TOKEN
| npm scripts, GitHub Actions, semantic-release
| package.json, workflows
Rule: Always set BOTH variables in mise [env] pointing to the same token file. Different tools check different variable names.
Alternative: 1Password Integration
For enhanced security with automatic token rotation:
[env]
GH_TOKEN = "{{ op_read('op://Engineering/GitHub Token/credential') }}"
With caching for performance:
[env]
GH_TOKEN = "{{ cache(key='gh_token', duration='1h', run='op read op://Engineering/GitHub Token/credential') }}"
Verification
/usr/bin/env bash << 'MISE_EOF'
for dir in ~/.claude ~/eon ~/own ~/scripts ~/459ecs; do
cd "$dir" && eval "$(mise hook-env -s bash)" && echo "$dir → $GH_ACCOUNT"
done
MISE_EOF
ADR Reference: GitHub Multi-Account Authentication
SSH ControlMaster Warning: If using multi-account SSH, ensure ControlMaster no is set for GitHub hosts in ~/.ssh/config. Cached connections can authenticate with the wrong account. See semantic-release authentication for troubleshooting.
Anti-Patterns
| mise exec -- script.py
| Forces mise dependency
| Use env vars with defaults
| Secrets in .mise.toml
| Visible in repo
| Use Doppler or redact = true
| No defaults in scripts | Breaks without mise | Always provide fallback
| Mixing env/tools resolution
| Order matters
| Use tools = true for tool-dependent vars
Task Orchestration Integration
When you detect workflow opportunities during mise configuration, prescriptively invoke the mise-tasks skill.
Detection Triggers
-
Multi-step workflows (test + build + deploy)
-
Repeatable project commands (lint, format, release)
-
Dependency chains (db-migrate depends on db-init)
-
File-tracked builds (sources/outputs caching)
Prescriptive AI Reminder
PRESCRIPTIVE: When detecting multi-step project workflows, invoke mise-tasks skill to generate appropriate [tasks] definitions with dependency management.
Example: From Environment to Tasks
Step 1: Configure environment (this skill):
[env]
DATABASE_URL = "postgresql://localhost/mydb"
_.python.venv = { path = ".venv", create = true }
Step 2: Define tasks (mise-tasks skill):
[tasks.test]
depends = ["lint"]
run = "pytest tests/"
[tasks.deploy]
depends = ["test", "build"]
run = "deploy.sh"
Tasks automatically inherit [env] values.
Additional Resources
For complete code patterns and examples, see: references/patterns.md
For task orchestration, see: mise-tasks skill - Dependencies, arguments, file tracking, watch mode
ADR Reference: When implementing mise configuration, create an ADR at docs/adr/YYYY-MM-DD-mise-env-centralized-config.md in your project.