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README.md

@@ -10,70 +10,6 @@
 
 Chronos is an efficient library for asynchronous programming and an alternative to Nim's asyncdispatch.
 
-## Core differences between the standard library asyncdispatch and Chronos
-
-1. Unified callback type `CallbackFunc`:
-
-   Current version of asyncdispatch uses many types of callbacks:
-
-   * `proc ()` is used in callSoon() callbacks and Future[T] completion callbacks.
-   * `proc (fut: Future[T])` is used in Future[T] completion callbacks.
-   * `proc (fd: AsyncFD, bytesTransferred: Dword, errcode: OSErrorCode)` is used in  Windows IO completion callbacks.
-   * `proc (fd: AsyncFD): bool` is used in Unix IO event callbacks.
-
-   Such a large number of different types creates big problems in the storage and processing of callbacks and in interaction between callbacks. Lack of ability to pass custom user data to
-   a callback also creates difficulties and inefficiency with passing custom, user-defined data needed for using closures (one more allocation).
-
-   To resolve this issue, we have introduced a unified callback type, `CallbackFunc`:
-
-   ```nim
-   type
-     CallbackFunc* = proc (arg: pointer = nil) {.gcsafe.}
-   ```
-   Also, one more type was introduced for the callback storage, `AsyncCallback`:
-
-   ```nim
-   type
-       AsyncCallback* = object
-         function*: CallbackFunc
-         udata*: pointer
-   ```
-
-2. The order of Future[T] completion callbacks:
-
-    Current version of asyncdispatch processes Future[T] completion callbacks in reverse order, but asyncdispatch2 schedules callbacks in forward order: https://github.com/nim-lang/Nim/issues/7197
-
-3. Changed the behavior of OS descriptor event callbacks:
-
-    For some unknown reason, the current version of asyncdispatch uses seq[T] to hold a list of descriptor event listeners. However, in the asynchronous environment, there is no need for a list of event listeners. In Chronos, there is only one place for one READ listener and one place for one WRITE listener.
-
-4. Removed the default timeout value for the poll() procedure, which allows incorrect usage of asyncdispatch and produces 500-ms timeouts in correct usage.
-
-5. Changed the behavior of the scheduler in the poll() procedure, and fixed the following issues:
-   * https://github.com/nim-lang/Nim/issues/7758
-   * https://github.com/nim-lang/Nim/issues/7197
-   * https://github.com/nim-lang/Nim/issues/7193
-   * https://github.com/nim-lang/Nim/issues/7192
-   * https://github.com/nim-lang/Nim/issues/6846
-   * https://github.com/nim-lang/Nim/issues/6929
-
-
-6. Chronos no longer uses `epochTime()`; instead, it uses the fastest time primitives for a specific OS, `fastEpochTime()`. Also, because MacOS supports only a millisecond resolution in `kqueue`, sub-millisecond resolution is not needed. For details, see https://github.com/nim-lang/Nim/issues/3909.
-
-7. Removed all IO primitives (`recv()`, `recvFrom()`, `connect()`, `accept()`, `send()`, and `sendTo()`) from the public API, and moved all their functionality into Transports.
-
-8. Introduced an `addTimer()` / `removeTimer()` callback interface.
-
-9. Introduced `removeReader()` for `addReader()` and `removeWriter()` for `addWriter()`.
-
-10. Changed the behavior of the `addReader()`, `addWriter()`, and `addTimer()` callbacks. Now, only the explicit removal of the callbacks must be supplied via `removeReader()`, `removeWriter()`, and `removeTimer()`.
-
-11. Added the support for the cross-platform `sendfile()` operation.
-
-12. Removed the expensive `AsyncEvent` and the support for hardware timers and `addProcess`. `addProcess` will be implemented as SubprocessTransport, while hardware-based `AsyncEvent` will be renamed to `ThreadAsyncEvent`.
-
-13. Added cheap synchronization primitives: `AsyncLock`, `AsyncEvent`, and `AsyncQueue[T]`.
-
 ## Documentation
 You can find more documentation, notes and examples in [Wiki](https://github.com/status-im/nim-chronos/wiki).