feat(docs): update CONTRIBUTING.md and README.md for BitGo fork

Update documentation to reflect this is a BitGo fork with altcoin support.
Clarify contribution guidelines, remove upstream-specific information,
and add details about Bitcoin Cash support.

Issue: BTC-2656

Co-authored-by: llm-git <[email protected]>

Author: OttoAllmendinger

CONTRIBUTING.md

@@ -1,22 +1,16 @@
-# Contributing to rust-bitcoin
+# Contributing to rust-bitcoin (BitGo Fork)
 
 :+1::tada: First off, thanks for taking the time to contribute! :tada::+1:
 
-The following is a set of guidelines for contributing to Rust Bitcoin
-implementation and other Rust Bitcoin-related projects, which are hosted in the
-[Rust Bitcoin Community](https://github.com/rust-bitcoin) on GitHub. These are
-mostly guidelines, not rules. Use your best judgment, and feel free to propose
-changes to this document in a pull request.
+This is BitGo's fork of rust-bitcoin that adds support for select altcoins.
+The following guidelines are adapted from the upstream project.
 
 #### Table Of Contents
 
 - [General](#general)
-- [Communication channels](#communication-channels)
-- [Asking questions](#asking-questions)
 - [Contribution workflow](#contribution-workflow)
   * [Preparing PRs](#preparing-prs)
   * [Peer review](#peer-review)
-  * [Repository maintainers](#repository-maintainers)
 - [Coding conventions](#coding-conventions)
   * [Naming conventions](#naming-conventions)
   * [Upgrading dependencies](#upgrading-dependencies)
@@ -29,41 +23,18 @@ changes to this document in a pull request.
 
 ## General
 
-The Rust Bitcoin project operates an open contributor model where anyone is
-welcome to contribute towards development in the form of peer review,
-documentation, testing and patches.
+This fork is maintained by BitGo to add altcoin support that the upstream
+rust-bitcoin project does not provide. We welcome contributions that:
 
-Anyone is invited to contribute without regard to technical experience,
-"expertise", OSS experience, age, or other concern. However, the development of
-standards & reference implementations demands a high-level of rigor, adversarial
-thinking, thorough testing and risk-minimization. Any bug may cost users real
-money. That being said, we deeply welcome people contributing for the first time
-to an open source project or pick up Rust while contributing. Don't be shy,
-you'll learn.
+- Fix bugs in Bitcoin or altcoin functionality
+- Add support for additional altcoins needed by BitGo
+- Keep us in sync with upstream rust-bitcoin improvements
 
+When contributing altcoin-specific code, please keep it isolated from core
+Bitcoin functionality to minimize merge conflicts with upstream.
 
-## Communication channels
-
-Communication about Rust Bitcoin happens primarily in
-[#bitcoin-rust](https://web.libera.chat/?channel=#bitcoin-rust) IRC chat on
-[Libera](https://libera.chat/) with the logs available at
-<https://gnusha.org/bitcoin-rust/> (starting from Jun 2021 and now on) and
-<https://gnusha.org/rust-bitcoin/> (historical archive before Jun 2021).
-
-Discussion about code base improvements happens in GitHub issues and on pull
-requests.
-
-Major projects are tracked [here](https://github.com/orgs/rust-bitcoin/projects).
-Major milestones are tracked [here](https://github.com/rust-bitcoin/rust-bitcoin/milestones).
-
-
-## Asking questions
-
-> **Note:** Please don't file an issue to ask a question. You'll get faster
-> results by using the resources below.
-
-We have a dedicated developer channel on IRC, #[email protected] where
-you may get helpful advice if you have questions.
+For upstream rust-bitcoin development, please contribute directly to the
+[upstream repository](https://github.com/rust-bitcoin/rust-bitcoin).
 
 
 ## Contribution workflow
@@ -111,8 +82,7 @@ Prerequisites that a PR must satisfy for merging into the `master` branch:
   reorder them during review and check that the new tests fail without the new
   code);
 * contain all inline docs for newly introduced API and pass doc tests;
-* be based on the recent `master` tip from the original repository at
-  <https://github.com/rust-bitcoin/rust-bitcoin>.
+* be based on the recent `master` tip from this repository.
 
 NB: reviewers may run more complex test/CI scripts, thus, satisfying all the
 requirements above is just a preliminary, but not necessary sufficient step for
@@ -134,53 +104,8 @@ grammar fixes.
 
 ### Repository maintainers
 
-Pull request merge requirements:
-- all CI test should pass,
-- at least two "accepts"/ACKs from the repository maintainers (see "refactor carve-out").
-- no reasonable "rejects"/NACKs from anybody who reviewed the code.
-
-Current list of the project maintainers:
-
-- [Andrew Poelstra](https://github.com/apoelstra)
-- [Steven Roose](https://github.com/stevenroose)
-- [Matt Corallo](https://github.com/TheBlueMatt)
-- [Elichai Turkel](https://github.com/elichai)
-- [Sanket Kanjalkar](https://github.com/sanket1729)
-- [Martin Habovštiak](https://github.com/Kixunil)
-- [Riccardo Casatta](https://github.com/RCasatta)
-- [Tobin Harding](https://github.com/tcharding)
-
-#### One ACK carve-out
-
-The repository is going through heavy refactoring and "trivial" API redesign
-(eg, rename `Foo::empty` to `Foo::new`) as we push towards API stabilization. As
-such reviewers are either bored or overloaded with notifications, hence we have
-created a carve out to the 2-ACK rule.
-
-We reserve the right to merge PRs with a single ACK [0], at any time, if they match
-any of the following conditions:
-
-0. PR has a single ACK and has sat open for at least two weeks with no comments,
-   questions, or NACKs.
-1. PR only touches CI i.e, only changes any of the test scripts and/or
-   stuff in `.github/workflows`.
-2. Non-content changing documentation fixes i.e., grammar/typos, spelling, full
-   stops, capital letters. Any change with more substance must still get two
-   ACKs.
-3. Code moves that do not change the API e.g., moving error types to a private
-   submodule and re-exporting them from the original module. Must not include
-   any code changes except to import paths. Requires absolutely no change to the
-   public API.
-4. PR has previously had two ACKs, had minimal changes, and gets a single ACK
-   from Andrew. This call is subjective, gives extra privileges, but also
-   requires extra responsibility/accountability (including running a bunch
-   of local CI checks before merging) [1].
-
-
-
-[0] - Obviously author and ACK'er must not be the same person.
-[1] - The aim is to reduce the burden of re-ACK'ing trivial changes and also
-      alleviate the problem of devs spread around the world in different timezones.
+This fork is maintained by the BitGo engineering team. Pull requests should be
+reviewed by at least one team member before merging.
 
 
 ## Coding conventions
@@ -417,12 +342,12 @@ We use SPDX license tags, all files should start with
 ## Security
 
 Security is the primary focus for this library; disclosure of security
-vulnerabilities helps prevent user loss of funds. If you believe a vulnerability
-may affect other implementations, please disclose this information according to
-the [security guidelines](./SECURITY.md), work on which is currently in progress.
-Before it is completed, feel free to send disclosure to Andrew Poelstra,
-[email protected], encrypted with his public key from
-<https://www.wpsoftware.net/andrew/andrew.gpg>.
+vulnerabilities helps prevent user loss of funds. If you believe you have found
+a security vulnerability, please report it through BitGo's security disclosure
+process or contact the BitGo security team directly.
+
+For vulnerabilities that may affect the upstream rust-bitcoin project, please
+also follow their [security guidelines](https://github.com/rust-bitcoin/rust-bitcoin/blob/master/SECURITY.md).
 
 
 ## Testing
@@ -438,10 +363,10 @@ the [readme](./README.md) for more information.
 
 ## Going further
 
-You may be interested in the guide by Jon Atack on
-[How to review Bitcoin Core PRs](https://github.com/jonatack/bitcoin-development/blob/master/how-to-review-bitcoin-core-prs.md)
-and [How to make Bitcoin Core PRs](https://github.com/jonatack/bitcoin-development/blob/master/how-to-make-bitcoin-core-prs.md).
-While there are differences between the projects in terms of context and
-maturity, many of the suggestions offered apply to this project.
+For more context on Bitcoin development practices, you may be interested in:
+
+- [Upstream rust-bitcoin repository](https://github.com/rust-bitcoin/rust-bitcoin)
+- [How to review Bitcoin Core PRs](https://github.com/jonatack/bitcoin-development/blob/master/how-to-review-bitcoin-core-prs.md)
+- [How to make Bitcoin Core PRs](https://github.com/jonatack/bitcoin-development/blob/master/how-to-make-bitcoin-core-prs.md)
 
-Overall, have fun :)
+Happy hacking!

README.md

@@ -1,38 +1,41 @@
 <div align="center">
-  <h1>Rust Bitcoin</h1>
+  <h1>Rust Bitcoin (BitGo Fork)</h1>
 
   <img alt="Rust Bitcoin logo by Hunter Trujillo, see license and source files under /logo" src="./logo/rust-bitcoin.png" width="300" />
 
-  <p>Library with support for de/serialization, parsing and executing on data-structures
-    and network messages related to Bitcoin.
+  <p>BitGo's fork of rust-bitcoin with support for Bitcoin and select altcoins
+    including Bitcoin Cash (BCH).
   </p>
 
   <p>
-    <a href="https://crates.io/crates/bitcoin"><img alt="Crate Info" src="https://img.shields.io/crates/v/bitcoin.svg"/></a>
     <a href="https://github.com/rust-bitcoin/rust-bitcoin/blob/master/LICENSE"><img alt="CC0 1.0 Universal Licensed" src="https://img.shields.io/badge/license-CC0--1.0-blue.svg"/></a>
-    <a href="https://github.com/rust-bitcoin/rust-bitcoin/actions?query=workflow%3AContinuous%20integration"><img alt="CI Status" src="https://github.com/rust-bitcoin/rust-bitcoin/workflows/Continuous%20integration/badge.svg"></a>
-    <a href="https://docs.rs/bitcoin"><img alt="API Docs" src="https://img.shields.io/badge/docs.rs-bitcoin-green"/></a>
     <a href="https://blog.rust-lang.org/2021/11/01/Rust-1.56.1.html"><img alt="Rustc Version 1.56.1+" src="https://img.shields.io/badge/rustc-1.56.1%2B-lightgrey.svg"/></a>
-    <a href="https://gnusha.org/bitcoin-rust/"><img alt="Chat on IRC" src="https://img.shields.io/badge/irc-%23bitcoin--rust%20on%20libera.chat-blue"></a>
-    <a href="https://github.com/model-checking/kani"><imp alt="kani" src="https://github.com/rust-bitcoin/rust-bitcoin/actions/workflows/kani.yaml/badge.svg"></a>
   </p>
 </div>
 
-[Documentation](https://docs.rs/bitcoin/)
+This is a [BitGo](https://www.bitgo.com/) fork of [rust-bitcoin](https://github.com/rust-bitcoin/rust-bitcoin)
+that extends the library with support for select altcoins. The upstream project does not support altcoins
+(see their [policy](#policy-on-altcoinsaltchains)), so we maintain this fork for our internal needs.
 
-Supports (or should support)
+## Altcoin Support
+
+This fork adds support for:
+
+* **Bitcoin Cash (BCH)**: SIGHASH_FORKID for replay-protected transactions, BCH-compatible PSBT signing
+
+See the `altcoins/` directory for specifications and test vectors.
+
+## Upstream Features
+
+All upstream rust-bitcoin features are supported:
 
 * De/serialization of Bitcoin protocol network messages
 * De/serialization of blocks and transactions
 * Script de/serialization
 * Private keys and address creation, de/serialization and validation (including full BIP32 support)
-* PSBT v0 de/serialization and all but the Input Finalizer role. Use [rust-miniscript](https://docs.rs/miniscript/latest/miniscript/psbt/index.html) to finalize.
-
-For JSONRPC interaction with Bitcoin Core, it is recommended to use
-[rust-bitcoincore-rpc](https://github.com/rust-bitcoin/rust-bitcoincore-rpc).
+* PSBT v0 de/serialization and all but the Input Finalizer role
 
-It is recommended to always use [cargo-crev](https://github.com/crev-dev/cargo-crev) to verify the
-trustworthiness of each of your dependencies, including this one.
+For upstream documentation, see [docs.rs/bitcoin](https://docs.rs/bitcoin/).
 
 ## Known limitations
 
@@ -59,11 +62,8 @@ and to expand on existing docs would be extremely appreciated.
 
 ## Contributing
 
-Contributions are generally welcome. If you intend to make larger changes please discuss them in an
-issue before PRing them to avoid duplicate work and architectural mismatches. If you have any
-questions or ideas you want to discuss please join us in
-[#bitcoin-rust](https://web.libera.chat/?channel=#bitcoin-rust) on
-[libera.chat](https://libera.chat).
+Contributions are welcome. If you intend to make larger changes please discuss them in an
+issue before PRing them to avoid duplicate work and architectural mismatches.
 
 For more information please see `./CONTRIBUTING.md`.
 
@@ -107,7 +107,7 @@ be usable without `std`. Both can be enabled without conflict.
 The library can be built and tested using [`cargo`](https://github.com/rust-lang/cargo/):
 
 ```
-git clone [email protected]:rust-bitcoin/rust-bitcoin.git
+git clone [email protected]:BitGo/rust-bitcoin.git
 cd rust-bitcoin
 cargo build
 ```
@@ -170,9 +170,8 @@ We have started using [kani](https://github.com/model-checking/kani), install wi
 
 ## Pull Requests
 
-Every PR needs at least two reviews to get merged. During the review phase maintainers and
-contributors are likely to leave comments and request changes. Please try to address them, otherwise
-your PR might get closed without merging after a longer time of inactivity. If your PR isn't ready
+PRs should be reviewed by at least one BitGo team member before merging. During the review phase,
+reviewers may leave comments and request changes. Please try to address them. If your PR isn't ready
 for review yet please mark it by prefixing the title with `WIP: `.
 
 ### CI Pipeline
@@ -197,12 +196,11 @@ Alternatively add symlinks in your `.git/hooks` directory to any of the githooks
 
 ## Policy on Altcoins/Altchains
 
-Since the altcoin landscape includes projects which [frequently appear and disappear, and are poorly
-designed anyway](https://download.wpsoftware.net/bitcoin/alts.pdf) we do not support any altcoins.
-Supporting Bitcoin properly is already difficult enough and we do not want to increase the
-maintenance burden and decrease API stability by adding support for other coins.
+The upstream rust-bitcoin project does not support altcoins. This BitGo fork adds support for
+select altcoins that we need for our business operations. We aim to keep altcoin-specific code
+isolated and minimize divergence from upstream to ease future merges.
 
-Our code is public domain so by all means fork it and go wild :)
+If you need altcoin support beyond what this fork provides, you're welcome to fork further.
 
 
 ## Release Notes