> ## Documentation Index
> Fetch the complete documentation index at: https://docs.sifr.sh/llms.txt
> Use this file to discover all available pages before exploring further.

# SIFR-STDLIB-0003: Embedded standard-library bootstrap failure.

> Embedded standard-library bootstrap failure.

`SIFR-STDLIB-0003` belongs to the **Standard library surface** diagnostic family. It means: embedded standard-library bootstrap failure.

## Why It Happens

The selected standard-library surface is not supported in this form. Use the documented `sifr.*` contract for the API you need.

<Info>
  Use `sifr --explain SIFR-STDLIB-0003` locally to see the renderer's exact message template and any machine-applicable suggestions for the compiler version you are running.
</Info>

## Erroneous Code

```python theme={null}
values = defaultdict()
```

## How To Fix It

Use the supported `sifr.*` surface and constructor shape. Some CPython conveniences are intentionally absent or require explicit arguments.

## Fixed Code

```python theme={null}
from sifr.collections import defaultdict

values = defaultdict(lambda: 0)
```

## Details

| Field                  | Value                                            |
| ---------------------- | ------------------------------------------------ |
| Code                   | `SIFR-STDLIB-0003`                               |
| Family                 | `STDLIB`                                         |
| Severity               | Error                                            |
| Stability              | stable                                           |
| Owner                  | `sifr_driver::stdlib::bootstrap`                 |
| Representative fixture | `crates/sifr_driver/src/tests/stdlib_exports.rs` |

See the [Error Codes index](/diagnostics/error-codes) for the complete catalog.