general: move to stable simplex 0.0.8, dedupe tests, track artifacts

.github/workflows/lint.yml

@@ -30,7 +30,7 @@ jobs:
           export SIMPLEX_DIR="$HOME/.simplex"
           curl -L https://raw.githubusercontent.com/BlockstreamResearch/smplx/master/simplexup/install | bash
           echo "$SIMPLEX_DIR/bin" >> "$GITHUB_PATH"
-          "$SIMPLEX_DIR/bin/simplexup" --install v0.0.6 --platform linux --arch amd64
+          "$SIMPLEX_DIR/bin/simplexup" --install v0.0.8 --platform linux --arch amd64
 
       - name: Cache cargo
         uses: Swatinem/rust-cache@v2
@@ -41,6 +41,11 @@ jobs:
         working-directory: crates/contracts
         run: simplex build
 
+      - name: Check committed artifacts are up to date
+        run: |
+          git add -N crates/contracts/src/artifacts
+          git diff --exit-code -- crates/contracts/src/artifacts
+
       - name: Format check
         run: cargo fmt --all --check
 

.github/workflows/tests.yml

@@ -33,7 +33,7 @@ jobs:
           export SIMPLEX_DIR="$HOME/.simplex"
           curl -L https://raw.githubusercontent.com/BlockstreamResearch/smplx/master/simplexup/install | bash
           echo "$SIMPLEX_DIR/bin" >> "$GITHUB_PATH"
-          "$SIMPLEX_DIR/bin/simplexup" --install v0.0.6 --platform linux --arch amd64
+          "$SIMPLEX_DIR/bin/simplexup" --install v0.0.8 --platform linux --arch amd64
 
       - name: Cache cargo
         uses: Swatinem/rust-cache@v2
@@ -68,7 +68,7 @@ jobs:
           export SIMPLEX_DIR="$HOME/.simplex"
           curl -L https://raw.githubusercontent.com/BlockstreamResearch/smplx/master/simplexup/install | bash
           echo "$SIMPLEX_DIR/bin" >> "$GITHUB_PATH"
-          "$SIMPLEX_DIR/bin/simplexup" --install v0.0.6 --platform linux --arch amd64
+          "$SIMPLEX_DIR/bin/simplexup" --install v0.0.8 --platform linux --arch amd64
 
       - name: Cache cargo
         uses: Swatinem/rust-cache@v2

CONTRIBUTING.md

@@ -1,3 +1,82 @@
+# Contributing
+
+## Development Setup
+
+### Prerequisites
+
+- Rust 1.91.0 or later (CI tests 1.91.0 and stable).
+- The [Simplex](https://github.com/BlockstreamResearch/smplx) CLI, pinned to
+  the same version as CI (see `.github/workflows/tests.yml`):
+
+  ```sh
+  curl -L https://raw.githubusercontent.com/BlockstreamResearch/smplx/master/simplexup/install | bash
+  simplexup --install v0.0.8
+  ```
+
+### Building
+
+```sh
+cargo build --workspace --all-features
+```
+
+Contract artifacts (`crates/contracts/src/artifacts`) are generated from the
+SimplicityHL sources in `crates/contracts/simf` and are checked in, so a plain
+`cargo build` works out of the box. Whenever you change a `.simf` source (or
+bump the Simplex toolchain), regenerate and commit them:
+
+```sh
+cd crates/contracts
+simplex build
+```
+
+CI regenerates the artifacts and fails if the committed ones are stale.
+
+### Testing
+
+Unit tests need no external services:
+
+```sh
+cargo test --workspace --all-features --lib
+```
+
+The regtest suite (`crates/contracts/tests`) runs against local `elementsd`
+and `electrs` instances and is driven by Simplex:
+
+```sh
+export ELEMENTSD_EXEC=/path/to/elementsd
+export ELECTRS_LIQUID_EXEC=/path/to/electrs
+simplex test
+```
+
+See the "Setup regtest binaries" step in `.github/workflows/tests.yml` for
+the exact binaries CI downloads.
+
+### Linting
+
+CI enforces formatting and a strict clippy profile:
+
+```sh
+cargo fmt --all --check
+cargo clippy --workspace --all-targets --all-features -- \
+    -D warnings -D clippy::all -D clippy::pedantic -D clippy::nursery \
+    -D clippy::cargo -A clippy::multiple_crate_versions
+```
+
+## Repository Layout
+
+- `crates/contracts/simf/`: SimplicityHL sources for the finance contracts;
+  `simplex build` compiles them into the generated (and committed)
+  `crates/contracts/src/artifacts`.
+- `crates/contracts/src/programs/`: Rust wrappers around the generated
+  finance contract artifacts (options, option offer).
+- `crates/contracts/src/state_management/`: standalone storage contract
+  examples; each embeds its own source from a `source_simf/` directory and is
+  gated behind a feature flag.
+- `crates/contracts/src/simplicityhl_core/`: shared compile/execute/taproot
+  helpers.
+- `crates/contracts/tests/`: regtest scenarios (`regtest/`), transaction
+  builders (`program_builder/`), and shared test utilities (`common/`).
+
 # PR Structure
 
 All changes must be submitted in the form of pull requests. Direct pushes