feat(plugins): migrate Python family to TypeBox v2; complete first‑party v2 set (Regex/Net/Path/Math/Time/File)\n\nfeat(smoke): add Net round‑trip sample and wire to plugin v2 smoke\n\nfeat(cli): add --emit-mir-json and runner emit+exit path\n\nchore(config): register Python v2 boxes in nyash.toml\n\nchore(loader): improve v2 diagnostics and ensure v2 shim dispatch\n\nchore(build): integrate ny-llvmc env gate in build_llvm.sh\n\nchore(tasks): update CURRENT_TASK with v2 Python/Net/emit flag

src/cli.rs

@@ -69,6 +69,8 @@ pub struct CliConfig {
     pub build_target: Option<String>,
     // Using (CLI)
     pub cli_usings: Vec<String>,
+    // Emit MIR JSON to a file and exit (bridge mode)
+    pub emit_mir_json: Option<String>,
 }
 
 impl CliConfig {
@@ -131,6 +133,12 @@ impl CliConfig {
                     .value_name("FILE")
                     .help("Read Ny JSON IR v0 from a file and execute via MIR Interpreter")
             )
+            .arg(
+                Arg::new("emit-mir-json")
+                    .long("emit-mir-json")
+                    .value_name("FILE")
+                    .help("Emit MIR JSON v0 to file (validation-friendly) and exit")
+            )
             .arg(
                 Arg::new("stage3")
                     .long("stage3")
@@ -482,6 +490,7 @@ impl CliConfig {
                 .get_many::<String>("using")
                 .map(|v| v.cloned().collect())
                 .unwrap_or_else(|| Vec::new()),
+            emit_mir_json: matches.get_one::<String>("emit-mir-json").cloned(),
         }
     }
 }
@@ -536,6 +545,7 @@ impl Default for CliConfig {
             build_profile: None,
             build_target: None,
             cli_usings: Vec::new(),
+            emit_mir_json: None,
         }
     }
 }

src/runner/dispatch.rs

@@ -171,6 +171,16 @@ pub(crate) fn execute_file_with_backend(runner: &NyashRunner, filename: &str) {
 
 impl NyashRunner {
     pub(crate) fn execute_mir_module(&self, module: &crate::mir::MirModule) {
+        // If CLI requested MIR JSON emit, write to file and exit immediately.
+        if let Some(path) = self.config.emit_mir_json.as_ref() {
+            let p = std::path::Path::new(path);
+            if let Err(e) = crate::runner::mir_json_emit::emit_mir_json_for_harness_bin(module, p) {
+                eprintln!("❌ MIR JSON emit error: {}", e);
+                std::process::exit(1);
+            }
+            println!("MIR JSON written: {}", p.display());
+            std::process::exit(0);
+        }
         use crate::backend::MirInterpreter;
         use crate::box_trait::{BoolBox, IntegerBox, StringBox};
         use crate::boxes::FloatBox;

src/runtime/plugin_loader_v2/enabled/loader.rs

@@ -159,6 +159,16 @@ impl PluginLoaderV2 {
                     let abi_ok = st.abi_tag == 0x5459_4258
                         && st.struct_size as usize >= std::mem::size_of::<NyashTypeBoxFfi>();
                     if !abi_ok {
+                        if dbg_on() {
+                            eprintln!(
+                                "[PluginLoaderV2] WARN: invalid TypeBox ABI for {}.{} (abi_tag=0x{:08x} size={} need>={})",
+                                lib_name,
+                                box_type,
+                                st.abi_tag,
+                                st.struct_size,
+                                std::mem::size_of::<NyashTypeBoxFfi>()
+                            );
+                        }
                         continue;
                     }
                     // Remember invoke_id in box_specs for (lib_name, box_type)
@@ -172,7 +182,19 @@ impl PluginLoaderV2 {
                             invoke_id: None,
                         });
                         entry.invoke_id = Some(invoke_id);
+                    } else if dbg_on() {
+                        eprintln!(
+                            "[PluginLoaderV2] WARN: TypeBox present but no invoke_id for {}.{} — plugin should export per-Box invoke",
+                            lib_name, box_type
+                        );
                     }
+                } else if dbg_on() {
+                    eprintln!(
+                        "[PluginLoaderV2] NOTE: TypeBox symbol not found for {}.{} (symbol='{}'). Migrate plugin to Nyash ABI v2 to enable per-Box dispatch.",
+                        lib_name,
+                        box_type,
+                        sym_name.trim_end_matches('\0')
+                    );
                 }
             }
         }
@@ -228,8 +250,24 @@ impl PluginLoaderV2 {
         let (lib_name, box_type) = self.find_box_by_type_id(config, &toml_value, type_id)?;
         let key = (lib_name.to_string(), box_type.to_string());
         let map = self.box_specs.read().ok()?;
-        let spec = map.get(&key)?;
-        spec.invoke_id
+        let spec = map.get(&key);
+        if let Some(s) = spec {
+            if s.invoke_id.is_none() && dbg_on() {
+                eprintln!(
+                    "[PluginLoaderV2] WARN: no per-Box invoke for {}.{} (type_id={}). Calls will fail with E_PLUGIN (-5) until plugin migrates to v2.",
+                    lib_name, box_type, type_id
+                );
+            }
+            s.invoke_id
+        } else {
+            if dbg_on() {
+                eprintln!(
+                    "[PluginLoaderV2] INFO: no TypeBox spec loaded for {}.{} (type_id={}).",
+                    lib_name, box_type, type_id
+                );
+            }
+            None
+        }
     }
 
     pub fn metadata_for_type_id(&self, type_id: u32) -> Option<PluginBoxMetadata> {

src/runtime/plugin_loader_v2/enabled/mod.rs

@@ -25,7 +25,6 @@ pub fn box_invoke_for_type_id(type_id: u32) -> Option<super::enabled::host_bridg
 }
 
 /// Library-level shim to dispatch a v2 per-Box invoke function using type_id
-#[no_mangle]
 pub extern "C" fn nyash_plugin_invoke_v2_shim(
     type_id: u32,
     method_id: u32,