obbba-breaks 0.1.2

Estimate OBBBA individual tax breaks: the increased standard deduction and the overtime/tips above-the-line deductions (2025-2028).
Documentation
# obbba-breaks

Estimate the **One Big Beautiful Bill Act (OBBBA)** individual income-tax breaks:
the **increased (and permanent) standard deduction** plus the temporary
**above-the-line deductions for qualified overtime and tips** (tax years
**2025–2028**). Pure, dependency-free Rust math — the same engine behind the
[TaxBreakCalc](https://taxbreakcalc.com/) OBBBA tax-break calculator.

## Important: estimates pending final IRS guidance

OBBBA (signed July 2025) made the larger TCJA standard deduction permanent, added
a small temporary boost for 2025–2028, and introduced the "no tax on overtime" /
"no tax on tips" above-the-line deductions. The headline numbers below are widely
reported, but the IRS was still finalizing implementation details (exact MAGI
definitions, which tips/OT amounts qualify, inflation indexing for future years)
through late 2025 and into 2026. **Every figure here is an estimate / model
input**, not a guarantee of any taxpayer's actual deduction. Confirm against final
IRS guidance and a qualified tax professional.

Default estimated parameters:

| Parameter                       | Single / HoH | Married Filing Jointly |
|---------------------------------|--------------|------------------------|
| 2025 base standard deduction    | `$15,750`    | `$31,500`              |
| Temporary add-on (2025–2028)    | `$750`       | `$1,500`               |
| Overtime / tips deduction cap   | `$12,500`    | `$25,000`              |
| Overtime / tips MAGI phase-out  | begins `$150,000` (single) / `$300,000` (joint); `$1` lost per `$10` MAGI over |

## Usage

```rust
use obbba_breaks::{standard_deduction, overtime_deduction, tips_deduction, total_deduction, FilingStatus};

// 2025 standard deduction for a single filer (15,750 + 750 = 16,500)
let sd = standard_deduction(FilingStatus::Single, 2025);
assert!((sd - 16_500.0).abs() < 1e-6);

// Qualified overtime + tips deductions stack on top
let t = total_deduction(FilingStatus::Single, 2025, 8_000.0, 5_000.0, 90_000.0);
assert!((t - 29_500.0).abs() < 1e-6);
```

Parameters are overridable via `StandardDeduction` / `QualifiedDeductionParams` so
the crate can track IRS guidance as it finalizes.

## Live calculator

For an interactive version of the tips deduction covered above, see the
[TaxBreakCalc on crate doc no tax](https://taxbreakcalc.com/no-tax-on-tips-calculator/) at TaxBreakCalc.

License: MIT