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+
+# Platform Support
+
+Darwin platforms are binary and source stable. Linux platforms follow semantic versioning. Windows follows semantic versioning.
+
+### Windows concerns
+
+Trying to perfectly unify Windows with Darwin and Linux at the API level is ultimately a futile endeavor. However, in some specific cases, Windows does have directly corresponding syscalls or near-equivalents.
+
+Windows-specific details are open to reevaluation pending more Windows expertise for the project.
+
+
+## API to syscall mapping
+
+### `Errno`
+
+#### Instance computed properties
+
+| API                | Darwin     | Linux      | Windows    |
+|:-------------------|:-----------|:-----------|:-----------|
+| `description`      | `strerror` | `strerror` | `strerror` |
+| `debugDescription` | `strerror` | `strerror` | `strerror` |
+
+
+### `FileDescriptor`
+
+#### Instance methods
+
+| API                          | Darwin      | Linux       | Windows                                            |
+|:-----------------------------|:------------|:------------|:---------------------------------------------------|
+| `open`                       | `open`      | `open`      | `_wsopen_s(..., _SH_DENYNO, _S_IREAD \| _S_IWRITE)` |
+| `close`                      | `close`     | `close`     | `_close`                                           |
+| `seek`                       | `lseek`     | `lseek`     | `_lseeki64`                                        |
+| `read`                       | `read`      | `read`      | `_read`                                            |
+| `read(fromAbsoluteOffset:)`  | `pread`     | `pread`     | *custom*                                           |
+| `write`                      | `write`     | `write`     | `_write`                                           |
+| `write(fromAbsoluteOffset:)` | `pwrite`    | `pwrite`    | *custom*                                           |
+| `duplicate`                  | `dup`       | `dup`       | `_dup`                                             |
+| `duplicate(as:)`             | `dup2`      | `dup2`      | `_dup2`                                            |
+| `resize`                     | `ftruncate` | `ftruncate` | *N/A*                                              |
+
+
+#### Static methods
+
+| API    | Darwin | Linux  | Windows |
+|:-------|:-------|:-------|:--------|
+| `pipe` | `pipe` | `pipe` | *N/A*   |
+
+<details><summary>*Windows notes*</summary>
+
+Windows has custom implementations for reading from or writing to an absolute offset within a file.
+
+File resizing and pipes are not available on Windows at this point.
+
+</details>
+
+
+## **Types**
+
+**TODO**
+
+## **Values**
+
+**TODO**
+
+
+
+
+