Add MEV-Share backrunner example (closes #38)

CHANGELOG.md

@@ -11,9 +11,13 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Benchmark comparison refreshed against current alloy crates (alloy-primitives 1.6.0, alloy-sol-types 1.6.0, alloy-dyn-abi 1.6.0, alloy-consensus 2.0.5, alloy-signer 2.0.5, alloy-rlp 0.3.15); bench/alloy-bench migrated from alloy-primitives 0.8 / alloy 0.6. New score: eth.zig wins 18/26 (alloy improved Keccak on larger inputs, hex encoding, RLP u256 decoding, and UniswapV4-style swap math)
 
 ### Added
+- MEV-Share backrunner example (`examples/08_mev_share_backrunner.zig`): a teaching bot that matches the MEV-Share SSE event stream against comptime-computed Uniswap V2/V3 swap selectors and composes a backrun bundle (user tx hash + signed EIP-1559 backrun tx), with a safe `DRY_RUN` default that prints the `mev_sendBundle` params instead of submitting (#38)
 - `mev_share` module: MEV-Share client mirroring `mev-share-client-ts` -- `sendTransaction` (eth_sendPrivateTransaction via `flashbots.Relay`), `simulateBundle` (mev_simBundle with `SimBundleOpts`/`SimBundleResult`), blocking SSE event stream subscription (`MevShareClient.on` with `PendingEvent`/`PendingTransaction`/`PendingBundle` and pure `parseEventData`), and `getEventHistory` (GET /api/v1/history) (#34)
 - `eth_sendPrivateTransaction` (MEV-Share private transactions) on `flashbots.Relay`: submit a single private transaction with hint preferences (calldata, contract_address, logs, function_selector), builder selection, fast mode, and max inclusion block (#40)
 
+### Fixed
+- `sse_transport.SseParser.feedLine`: replaced the removed `std.mem.trimRight` with `std.mem.trimEnd` and gave the line-parse result an explicit struct type. These were latent Zig 0.16 migration misses that only surfaced when `feedLine` was semantically analyzed (it is not referenced by the unit-test root), and broke any consumer of `MevShareClient.on` -- surfaced while building the MEV-Share backrunner example (#38)
+
 ## [0.5.0] - 2026-06-10
 
 ### Changed

README.md

@@ -251,6 +251,7 @@ The [`examples/`](examples/) directory contains self-contained programs demonstr
 | `05_read_erc20` | ERC-20 module API showcase | Yes |
 | `06_hd_wallet` | BIP-44 HD wallet derivation | No |
 | `07_comptime_selectors` | Comptime function selectors | No |
+| `08_mev_share_backrunner` | MEV-Share backrunner bot (SSE stream + bundle) | No (dry-run) |
 
 Run any example:
 

docs/content/docs/examples.mdx

@@ -14,6 +14,7 @@ The [`examples/`](https://github.com/StrobeLabs/eth.zig/tree/main/examples) dire
 | `05_read_erc20` | ERC-20 module API showcase | Yes |
 | `06_hd_wallet` | BIP-44 HD wallet derivation | No |
 | `07_comptime_selectors` | Comptime function selectors | No |
+| `08_mev_share_backrunner` | MEV-Share backrunner bot (SSE stream + bundle) | No (dry-run) |
 
 Run any example:
 
@@ -111,3 +112,45 @@ try mc.addCall(token_addr, eth.erc20.selectors.balanceOf, .{holder_addr});
 try mc.addCall(token_addr, eth.erc20.selectors.totalSupply, .{});
 const results = try mc.execute();
 ```
+
+## MEV-Share Backrunner
+
+`08_mev_share_backrunner` is a teaching example that ties together comptime
+selectors, the MEV-Share SSE stream, EIP-1559 signing, and bundle composition.
+It subscribes to the pending-transaction event stream, matches hints against a
+comptime-computed table of Uniswap swap selectors, and builds a backrun bundle
+(the user's tx hash followed by a signed backrun tx). It defaults to a safe
+`DRY_RUN` mode that prints the `mev_sendBundle` params it would submit, and
+points at Sepolia by default so the subscription flow can be exercised with no
+mainnet funds.
+
+```zig
+const eth = @import("eth");
+
+// Comptime: the swap selector is hashed by the compiler.
+const v2_swap = comptime eth.keccak.selector(
+    "swapExactTokensForTokens(uint256,uint256,address[],address,uint256)",
+);
+
+var client = eth.mev_share.MevShareClient.init(allocator, relay_url, stream_url, auth_key);
+defer client.deinit();
+
+// Subscribe to the SSE stream; the callback fires per pending-tx hint.
+try client.on(&onEvent);
+
+// Inside onEvent: match the revealed selector, then compose the bundle.
+const body = [_]eth.flashbots.MevBundleBody{
+    .{ .hash = user_tx_hash }, // the user's pending swap
+    .{ .tx = .{ .data = signed_backrun_tx } }, // our backrun
+};
+_ = try client.relay.mevSendBundle(.{
+    .body = &body,
+    .inclusion = .{ .block = target_block, .max_block = target_block + 2 },
+});
+```
+
+Run it (dry-run, against the Sepolia matchmaker):
+
+```bash
+cd examples && zig build && DRY_RUN=1 ./zig-out/bin/08_mev_share_backrunner
+```