## Profiles

Profiles let you maintain different configurations for different scenarios. The `default` profile is always active, and other profiles inherit from it.

### Creating profiles

Define profiles in `foundry.toml`:

```toml [foundry.toml]
[profile.default]
src = "src"
out = "out"
libs = ["lib"]
optimizer = true
optimizer_runs = 200

[profile.ci]
verbosity = 3
fuzz = { runs = 10000 }

[profile.lite]
optimizer = false
fuzz = { runs = 32 }
```

### Selecting a profile

Set the `FOUNDRY_PROFILE` environment variable:

:::code-group
```bash [Single command]
$ FOUNDRY_PROFILE=ci forge test
```

```bash [Shell session]
$ export FOUNDRY_PROFILE=ci
$ forge test
$ forge build
```
:::

### Common profile patterns

#### CI profile

Increase fuzz runs and verbosity for thorough testing in CI:

```toml [foundry.toml]
[profile.ci]
verbosity = 3
fuzz = { runs = 10000, seed = "0x1" }
invariant = { runs = 1000 }
```

#### Development profile

Fast iteration with minimal optimization:

```toml [foundry.toml]
[profile.lite]
optimizer = false
fuzz = { runs = 32 }
via_ir = false
```

#### Production profile

Maximum optimization for deployment:

```toml [foundry.toml]
[profile.production]
optimizer = true
optimizer_runs = 1000000
via_ir = true
bytecode_hash = "none"
```

### Profile inheritance

All profiles inherit from `default`. You only need to specify values that differ:

```toml [foundry.toml]
[profile.default]
src = "src"
out = "out"
libs = ["lib"]
solc_version = "0.8.28"
optimizer = true
optimizer_runs = 200

# Inherits everything from default, overrides optimizer_runs
[profile.production]
optimizer_runs = 1000000
```

### Environment variable overrides

Override any configuration value with environment variables prefixed with `FOUNDRY_` or `DAPP_`:

```bash
# Override optimizer runs
$ FOUNDRY_OPTIMIZER_RUNS=500 forge build

# Override solc version
$ FOUNDRY_SOLC_VERSION=0.8.25 forge build
```

This is useful for CI or quick one-off builds without modifying `foundry.toml`.