Aider Configuration Best Practices

Configure Aider AI pair programming tool with production-ready settings for optimal coding assistance, git integration, and workflow automation.

What This Does

Sets up a comprehensive `.aider.conf.yml` configuration file that optimizes Aider for:

Instructions

1. **Determine Configuration Location**

- Place `.aider.conf.yml` in your home directory (`~/`) for global settings

- Or place at the root of your git repository for project-specific settings

- Repository configs override global configs

2. **Create Configuration File**

- Create `.aider.conf.yml` with the following optimized settings:

```yaml

Main model - fast and cost-effective

model: openrouter/google/gemini-2.5-flash

Weak model for summaries and commit messages

weak-model: anthropic/claude-3-5-haiku-20241022

Architect mode settings

auto-accept-architect: false

Caching for performance

cache-prompts: true

cache-keepalive-pings: 12

Terminal experience

dark-mode: true

stream: true

show-diffs: true

vim: true

notifications: true

Git integration

auto-commits: true

watch-files: true

Always confirm

yes-always: true

```

3. **Add API Keys (Choose One Method)**

**Option A: In config file (OpenAI/Anthropic only)**

```yaml

openai-api-key: sk-...

anthropic-api-key: sk-ant-...

```

**Option B: Environment file (recommended for all providers)**

- Create `.env` file in git root:

```bash

OPENROUTER_API_KEY=sk-or-...

ANTHROPIC_API_KEY=sk-ant-...

OPENAI_API_KEY=sk-...

GEMINI_API_KEY=...

```

**Option C: Use --api-key flag**

```yaml

api-key:

- openrouter=sk-or-...

- anthropic=sk-ant-...

```

4. **Customize Model Selection**

**For different speed/cost tradeoffs:**

```yaml

# Maximum quality

model: anthropic/claude-3-7-sonnet-20250219

# Balanced quality/speed

model: gemini/gemini-2.5-pro-preview-03-25

# Fast and economical (recommended)

model: openrouter/google/gemini-2.5-flash

```

5. **Configure Git Behavior**

```yaml

# Disable auto-commits if you prefer manual control

auto-commits: false

# Enable commit attribution

attribute-author: true

attribute-committer: true

# Prefix commit messages

attribute-commit-message-committer: true

```

6. **Set Up Linting and Testing**

```yaml

# Enable auto-linting after changes

auto-lint: true

# Configure lint commands per language

lint-cmd:

- "python: ruff check --fix"

- "typescript: eslint --fix"

- "go: golangci-lint run --fix"

# Configure test command

test-cmd: "npm test"

auto-test: true

```

7. **Optimize Repo Map Settings**

```yaml

# Increase token budget for larger repos

map-tokens: 2048

# Control refresh frequency

map-refresh: auto # Options: auto, always, files, manual

# Adjust multiplier for context without specific files

map-multiplier-no-files: 2

```

8. **Configure History and Logging**

```yaml

# Custom history file locations

input-history-file: .aider.input.history

chat-history-file: .aider.chat.history.md

# Restore previous chat on startup

restore-chat-history: true

# Log all LLM interactions for debugging

llm-history-file: .aider.llm.history

```

9. **Test Configuration**

```bash

# Start aider to verify config is loaded

aider

# Check that your model is active

/model

# Verify git integration

/git

```

10. **Add .aiderignore for Exclusions**

- Create `.aiderignore` in git root to exclude files:

```

# Build outputs

dist/

build/

*.pyc

# Dependencies

node_modules/

vendor/

# Large data files

*.db

*.sqlite

data/

```

Key Configuration Sections

**Model Settings:**

**Git Integration:**

**Performance:**

**User Experience:**

Important Notes

Common Workflows

**Quick Setup:**

```bash

cd ~/

curl -O https://example.com/.aider.conf.yml

Edit API keys

aider

```

**Project-Specific Config:**

```bash

cd your-project/

cp ~/.aider.conf.yml .aider.conf.yml

Customize for project

git add .aider.conf.yml

```

**Switch Models:**

```yaml

In .aider.conf.yml

model: anthropic/claude-3-7-sonnet-20250219 # High quality

or

model: gemini/gemini-2.5-flash # Fast and cheap

```