diff --git a/rewatch/src/build.rs b/rewatch/src/build.rs
index 88394eddda2..612d49eb183 100644
--- a/rewatch/src/build.rs
+++ b/rewatch/src/build.rs
@@ -436,8 +436,21 @@ pub fn incremental_build(
 }
 
 fn log_config_warnings(build_state: &BuildCommandState) {
-    build_state.packages.iter().for_each(|(_, package)| {
-        // Only warn for local dependencies, not external packages
+    let mut packages: Vec<_> = build_state.packages.values().collect();
+    packages.sort_by(|a, b| a.name.cmp(&b.name));
+    packages.iter().for_each(|package| {
+        let deprecations = package.config.get_deprecations();
+        if !deprecations.is_empty() {
+            // External consumers can't fix deprecations themselves, so we
+            // point them at the package's issue tracker when we can find one.
+            let issue_tracker_url = if package.is_local_dep {
+                None
+            } else {
+                crate::build::packages::read_issue_tracker_url(&package.path)
+            };
+            log_deprecations(&package.name, deprecations, issue_tracker_url.as_deref());
+        }
+
         if package.is_local_dep {
             package
                 .config
@@ -454,6 +467,44 @@ fn log_config_warnings(build_state: &BuildCommandState) {
     });
 }
 
+fn log_deprecations(
+    package_name: &str,
+    deprecations: &[crate::config::DeprecationWarning],
+    issue_tracker_url: Option<&str>,
+) {
+    let mut message = format!(
+        "Package '{package_name}' uses deprecated config (support will be removed in a future version):"
+    );
+    for deprecation in deprecations {
+        let line = match deprecation {
+            crate::config::DeprecationWarning::BsconfigJson => {
+                "  - filename 'bsconfig.json' — rename to 'rescript.json'"
+            }
+            crate::config::DeprecationWarning::BsDependencies => {
+                "  - field 'bs-dependencies' — use 'dependencies' instead"
+            }
+            crate::config::DeprecationWarning::BsDevDependencies => {
+                "  - field 'bs-dev-dependencies' — use 'dev-dependencies' instead"
+            }
+            crate::config::DeprecationWarning::BscFlags => {
+                "  - field 'bsc-flags' — use 'compiler-flags' instead"
+            }
+            crate::config::DeprecationWarning::CjsModule => {
+                "  - module 'cjs' in package-specs — use 'commonjs' instead"
+            }
+            crate::config::DeprecationWarning::Es6Module => {
+                "  - module 'es6' in package-specs — use 'esmodule' instead"
+            }
+        };
+        message.push('\n');
+        message.push_str(line);
+    }
+    if let Some(url) = issue_tracker_url {
+        message.push_str(&format!("\nPlease report this to the package maintainer: {url}"));
+    }
+    eprintln!("\n{}", style(message).yellow());
+}
+
 fn log_unsupported_config_field(package_name: &str, field_name: &str) {
     let warning = format!(
         "The field '{field_name}' found in the package config of '{package_name}' is not supported by ReScript 12's new build system."
diff --git a/rewatch/src/build/packages.rs b/rewatch/src/build/packages.rs
index a936b415f65..f5d16989042 100644
--- a/rewatch/src/build/packages.rs
+++ b/rewatch/src/build/packages.rs
@@ -246,7 +246,13 @@ fn get_source_dirs(source: config::Source, sub_path: Option<PathBuf>) -> AHashSe
 
 pub fn read_config(package_dir: &Path) -> Result<Config> {
     let rescript_json_path = package_dir.join("rescript.json");
-    Config::new(&rescript_json_path)
+    let bsconfig_json_path = package_dir.join("bsconfig.json");
+
+    if rescript_json_path.exists() {
+        Config::new(&rescript_json_path)
+    } else {
+        Config::new(&bsconfig_json_path)
+    }
 }
 
 pub fn read_dependency(
@@ -446,12 +452,52 @@ pub fn read_package_name(package_dir: &Path) -> Result<String> {
         return Ok(name);
     }
 
+    if let Some(name) = read_name("bsconfig.json")? {
+        return Ok(name);
+    }
+
     Err(anyhow!(
         "No name field found in package.json or rescript.json in {}",
         package_dir.to_string_lossy()
     ))
 }
 
+/// Looks up the best-effort issue tracker URL for a package by reading its
+/// package.json, preferring `bugs.url`, then deriving from `repository`.
+/// Returns None if no tracker could be inferred.
+pub fn read_issue_tracker_url(package_dir: &Path) -> Option<String> {
+    let contents = fs::read_to_string(package_dir.join("package.json")).ok()?;
+    let json: serde_json::Value = serde_json::from_str(&contents).ok()?;
+
+    let extract_url = |v: &serde_json::Value| -> Option<String> {
+        match v {
+            serde_json::Value::String(s) => Some(s.to_owned()),
+            serde_json::Value::Object(o) => o.get("url").and_then(|u| u.as_str()).map(String::from),
+            _ => None,
+        }
+    };
+
+    if let Some(bugs_url) = json.get("bugs").and_then(extract_url) {
+        return Some(bugs_url);
+    }
+
+    json.get("repository")
+        .and_then(extract_url)
+        .map(|repo| issues_url_from_repository(&repo))
+}
+
+fn issues_url_from_repository(repo: &str) -> String {
+    let cleaned = repo.trim_start_matches("git+").trim_end_matches(".git");
+
+    // npm shorthand (no scheme, no user@): treat as github-style "owner/repo"
+    if !cleaned.contains("://") && !cleaned.contains('@') {
+        let path = cleaned.trim_start_matches("github:");
+        return format!("https://github.com/{path}/issues");
+    }
+
+    format!("{cleaned}/issues")
+}
+
 fn make_package(
     config: config::Config,
     package_path: &Path,
@@ -1042,7 +1088,7 @@ pub fn validate_packages_dependencies(packages: &AHashMap<String, Package>) -> b
 mod test {
     use crate::config;
 
-    use super::{Namespace, Package, read_package_name};
+    use super::{Namespace, Package, read_issue_tracker_url, read_package_name};
     use ahash::{AHashMap, AHashSet};
     use std::fs;
     use std::path::PathBuf;
@@ -1176,4 +1222,77 @@ mod test {
             )
         );
     }
+
+    fn write_pkg_json(dir: &std::path::Path, body: &str) {
+        fs::write(dir.join("package.json"), body).expect("package.json should be written");
+    }
+
+    #[test]
+    fn issue_tracker_url_prefers_bugs_url_string() {
+        let temp_dir = TempDir::new().unwrap();
+        write_pkg_json(
+            temp_dir.path(),
+            r#"{"name":"x","bugs":"https://example.com/issues"}"#,
+        );
+        assert_eq!(
+            read_issue_tracker_url(temp_dir.path()),
+            Some("https://example.com/issues".to_string())
+        );
+    }
+
+    #[test]
+    fn issue_tracker_url_prefers_bugs_object_url() {
+        let temp_dir = TempDir::new().unwrap();
+        write_pkg_json(
+            temp_dir.path(),
+            r#"{"name":"x","bugs":{"url":"https://example.com/report"}}"#,
+        );
+        assert_eq!(
+            read_issue_tracker_url(temp_dir.path()),
+            Some("https://example.com/report".to_string())
+        );
+    }
+
+    #[test]
+    fn issue_tracker_url_derives_from_repository_git_url() {
+        let temp_dir = TempDir::new().unwrap();
+        write_pkg_json(
+            temp_dir.path(),
+            r#"{"name":"x","repository":"git+https://github.com/owner/repo.git"}"#,
+        );
+        assert_eq!(
+            read_issue_tracker_url(temp_dir.path()),
+            Some("https://github.com/owner/repo/issues".to_string())
+        );
+    }
+
+    #[test]
+    fn issue_tracker_url_derives_from_repository_object() {
+        let temp_dir = TempDir::new().unwrap();
+        write_pkg_json(
+            temp_dir.path(),
+            r#"{"name":"x","repository":{"type":"git","url":"https://github.com/owner/repo.git"}}"#,
+        );
+        assert_eq!(
+            read_issue_tracker_url(temp_dir.path()),
+            Some("https://github.com/owner/repo/issues".to_string())
+        );
+    }
+
+    #[test]
+    fn issue_tracker_url_handles_shorthand() {
+        let temp_dir = TempDir::new().unwrap();
+        write_pkg_json(temp_dir.path(), r#"{"name":"x","repository":"owner/repo"}"#);
+        assert_eq!(
+            read_issue_tracker_url(temp_dir.path()),
+            Some("https://github.com/owner/repo/issues".to_string())
+        );
+    }
+
+    #[test]
+    fn issue_tracker_url_returns_none_without_hints() {
+        let temp_dir = TempDir::new().unwrap();
+        write_pkg_json(temp_dir.path(), r#"{"name":"x"}"#);
+        assert_eq!(read_issue_tracker_url(temp_dir.path()), None);
+    }
 }
diff --git a/rewatch/src/config.rs b/rewatch/src/config.rs
index 1f0ea703489..44c4885695c 100644
--- a/rewatch/src/config.rs
+++ b/rewatch/src/config.rs
@@ -155,9 +155,9 @@ pub struct PackageSpec {
 
 #[derive(Deserialize, Debug, Clone, Eq, PartialEq)]
 pub enum PackageModule {
-    #[serde(rename = "commonjs")]
+    #[serde(rename = "commonjs", alias = "cjs")]
     CommonJs,
-    #[serde(rename = "esmodule")]
+    #[serde(rename = "esmodule", alias = "es6")]
     EsModule,
 }
 
@@ -244,7 +244,14 @@ pub struct JsPostBuild {
 }
 
 #[derive(Debug, Clone, Copy, PartialEq, PartialOrd)]
-pub enum DeprecationWarning {}
+pub enum DeprecationWarning {
+    BsconfigJson,
+    BsDependencies,
+    BsDevDependencies,
+    BscFlags,
+    CjsModule,
+    Es6Module,
+}
 
 #[derive(Debug, Clone, Eq, PartialEq, Hash)]
 pub enum ExperimentalFeature {
@@ -293,13 +300,14 @@ pub struct Config {
     pub package_specs: Option<OneOrMore<PackageSpec>>,
     pub warnings: Option<Warnings>,
     pub suffix: Option<String>,
+    #[serde(alias = "bs-dependencies")]
     pub dependencies: Option<Vec<String>>,
-    #[serde(rename = "dev-dependencies")]
+    #[serde(rename = "dev-dependencies", alias = "bs-dev-dependencies")]
     pub dev_dependencies: Option<Vec<String>>,
     #[serde(rename = "ppx-flags")]
     pub ppx_flags: Option<Vec<OneOrMore<String>>>,
 
-    #[serde(rename = "compiler-flags")]
+    #[serde(rename = "compiler-flags", alias = "bsc-flags")]
     pub compiler_flags: Option<Vec<OneOrMore<String>>>,
 
     pub namespace: Option<NamespaceConfig>,
@@ -459,8 +467,9 @@ impl Config {
 
     /// Try to convert a config from a string to a config struct
     pub fn new_from_json_string(config_str: &str) -> Result<Self> {
-        if let Ok(value) = serde_json::from_str::<serde_json::Value>(config_str) {
-            validate_package_specs_value(&value)?;
+        let raw_value = serde_json::from_str::<serde_json::Value>(config_str).ok();
+        if let Some(value) = raw_value.as_ref() {
+            validate_package_specs_value(value)?;
         }
 
         let mut deserializer = serde_json::Deserializer::from_str(config_str);
@@ -478,6 +487,29 @@ impl Config {
                     }
                 })?;
 
+        if let Some(value) = raw_value.as_ref().and_then(|v| v.as_object()) {
+            for (raw_key, warning) in [
+                ("bs-dependencies", DeprecationWarning::BsDependencies),
+                ("bs-dev-dependencies", DeprecationWarning::BsDevDependencies),
+                ("bsc-flags", DeprecationWarning::BscFlags),
+            ] {
+                if value.contains_key(raw_key) {
+                    config.deprecation_warnings.push(warning);
+                }
+            }
+        }
+
+        if let Some(value) = raw_value.as_ref() {
+            for (legacy_module, warning) in [
+                ("cjs", DeprecationWarning::CjsModule),
+                ("es6", DeprecationWarning::Es6Module),
+            ] {
+                if uses_module_alias(value, legacy_module) {
+                    config.deprecation_warnings.push(warning);
+                }
+            }
+        }
+
         config.handle_deprecations()?;
         config.unknown_fields = unknown_fields;
 
@@ -485,6 +517,9 @@ impl Config {
     }
 
     fn set_path(&mut self, path: PathBuf) -> Result<()> {
+        if path.file_name().and_then(|n| n.to_str()) == Some("bsconfig.json") {
+            self.deprecation_warnings.push(DeprecationWarning::BsconfigJson);
+        }
         self.path = path;
         Ok(())
     }
@@ -805,6 +840,19 @@ fn resolve_spec_in_source(spec: &serde_json::Value) -> bool {
         .unwrap_or(true)
 }
 
+fn uses_module_alias(value: &serde_json::Value, alias: &str) -> bool {
+    let specs = match value.get("package-specs") {
+        Some(specs) => specs,
+        None => return false,
+    };
+    let spec_has_alias =
+        |spec: &serde_json::Value| -> bool { spec.get("module").and_then(|m| m.as_str()) == Some(alias) };
+    match specs {
+        serde_json::Value::Array(specs) => specs.iter().any(spec_has_alias),
+        _ => spec_has_alias(specs),
+    }
+}
+
 fn validate_package_spec_value(value: &serde_json::Value) -> Result<()> {
     let module = match value.get("module") {
         Some(module) => module,
@@ -817,7 +865,7 @@ fn validate_package_spec_value(value: &serde_json::Value) -> Result<()> {
     };
 
     match module {
-        "commonjs" | "esmodule" => Ok(()),
+        "commonjs" | "cjs" | "esmodule" | "es6" => Ok(()),
         other => Err(anyhow!(
             "Module system \"{other}\" is unsupported. Expected \"commonjs\" or \"esmodule\"."
         )),
@@ -1130,6 +1178,31 @@ pub mod tests {
         assert!(config.get_deprecations().is_empty());
     }
 
+    #[test]
+    fn test_bs_dependencies_alias() {
+        let json = r#"
+        {
+            "name": "testrepo",
+            "sources": {
+                "dir": "src",
+                "subdirs": true
+            },
+            "package-specs": [
+                {
+                "module": "esmodule",
+                "in-source": true
+                }
+            ],
+            "suffix": ".mjs",
+            "bs-dependencies": [ "@testrepo/main" ]
+        }
+        "#;
+
+        let config = Config::new_from_json_string(json).expect("a valid json string");
+        assert_eq!(config.dependencies, Some(vec!["@testrepo/main".to_string()]));
+        assert_eq!(config.get_deprecations(), [DeprecationWarning::BsDependencies]);
+    }
+
     #[test]
     fn test_dev_dependencies() {
         let json = r#"
@@ -1156,7 +1229,7 @@ pub mod tests {
     }
 
     #[test]
-    fn test_package_specs_es6_global_deprecation() {
+    fn test_bs_dev_dependencies_alias() {
         let json = r#"
         {
             "name": "testrepo",
@@ -1166,21 +1239,22 @@ pub mod tests {
             },
             "package-specs": [
                 {
-                "module": "es6-global",
+                "module": "esmodule",
                 "in-source": true
                 }
             ],
-            "suffix": ".mjs"
+            "suffix": ".mjs",
+            "bs-dev-dependencies": [ "@testrepo/main" ]
         }
         "#;
 
-        let err = Config::new_from_json_string(json).unwrap_err();
-        let message = err.to_string();
-        assert!(message.contains("Module system \"es6-global\" is unsupported"));
+        let config = Config::new_from_json_string(json).expect("a valid json string");
+        assert_eq!(config.dev_dependencies, Some(vec!["@testrepo/main".to_string()]));
+        assert_eq!(config.get_deprecations(), [DeprecationWarning::BsDevDependencies]);
     }
 
     #[test]
-    fn test_package_specs_es6_deprecation() {
+    fn test_package_specs_es6_global_deprecation() {
         let json = r#"
         {
             "name": "testrepo",
@@ -1190,7 +1264,7 @@ pub mod tests {
             },
             "package-specs": [
                 {
-                "module": "es6",
+                "module": "es6-global",
                 "in-source": true
                 }
             ],
@@ -1200,7 +1274,25 @@ pub mod tests {
 
         let err = Config::new_from_json_string(json).unwrap_err();
         let message = err.to_string();
-        assert!(message.contains("Module system \"es6\" is unsupported"));
+        assert!(message.contains("Module system \"es6-global\" is unsupported"));
+    }
+
+    #[test]
+    fn test_es6_module_alias() {
+        let json = r#"
+        {
+            "name": "testrepo",
+            "sources": { "dir": "src", "subdirs": true },
+            "package-specs": [ { "module": "es6", "in-source": true } ],
+            "suffix": ".mjs"
+        }
+        "#;
+
+        let config = Config::new_from_json_string(json).expect("a valid json string");
+        let specs = config.get_package_specs();
+        assert_eq!(specs.len(), 1);
+        assert_eq!(specs[0].module, PackageModule::EsModule);
+        assert_eq!(config.get_deprecations(), [DeprecationWarning::Es6Module]);
     }
 
     #[test]
@@ -1296,6 +1388,49 @@ pub mod tests {
         assert!(config.get_deprecations().is_empty());
     }
 
+    #[test]
+    fn test_cjs_module_alias() {
+        let json = r#"
+        {
+            "name": "testrepo",
+            "sources": { "dir": "src", "subdirs": true },
+            "package-specs": [ { "module": "cjs", "in-source": true } ],
+            "suffix": ".js"
+        }
+        "#;
+
+        let config = Config::new_from_json_string(json).expect("a valid json string");
+        let specs = config.get_package_specs();
+        assert_eq!(specs.len(), 1);
+        assert_eq!(specs[0].module, PackageModule::CommonJs);
+        assert_eq!(config.get_deprecations(), [DeprecationWarning::CjsModule]);
+    }
+
+    #[test]
+    fn test_bsc_flags_alias() {
+        let json = r#"
+        {
+            "name": "testrepo",
+            "sources": {
+                "dir": "src",
+                "subdirs": true
+            },
+            "package-specs": [
+                {
+                "module": "esmodule",
+                "in-source": true
+                }
+            ],
+            "suffix": ".mjs",
+            "bsc-flags": [ "-w" ]
+        }
+        "#;
+
+        let config = Config::new_from_json_string(json).expect("a valid json string");
+        assert!(config.compiler_flags.is_some());
+        assert_eq!(config.get_deprecations(), [DeprecationWarning::BscFlags]);
+    }
+
     fn test_find_is_type_dev(source: OneOrMore<Source>, path: &Path, expected: bool) {
         let config = Config {
             name: String::from("testrepo"),
@@ -1501,4 +1636,22 @@ pub mod tests {
             "Error should include the missing config path, got: {error}"
         );
     }
+
+    #[test]
+    fn test_bsconfig_json_filename_deprecation() {
+        let tmp = tempfile::tempdir().expect("tempdir");
+        let path = tmp.path().join("bsconfig.json");
+        std::fs::write(
+            &path,
+            r#"{ "name": "legacy", "sources": { "dir": "src", "subdirs": true } }"#,
+        )
+        .expect("write");
+
+        let config = Config::new(&path).expect("a valid bsconfig.json");
+        assert!(
+            config
+                .get_deprecations()
+                .contains(&DeprecationWarning::BsconfigJson)
+        );
+    }
 }
diff --git a/rewatch/src/helpers.rs b/rewatch/src/helpers.rs
index 600dd34ab69..876fb1beb39 100644
--- a/rewatch/src/helpers.rs
+++ b/rewatch/src/helpers.rs
@@ -513,7 +513,7 @@ pub fn compute_file_hash(path: &Path) -> Option<blake3::Hash> {
 }
 
 fn has_rescript_config(path: &Path) -> bool {
-    path.join("rescript.json").exists()
+    path.join("rescript.json").exists() || path.join("bsconfig.json").exists()
 }
 
 // traverse up the directory tree until we find a config.json, if not return None
diff --git a/rewatch/src/watcher.rs b/rewatch/src/watcher.rs
index d6aba426f92..aa951cbe4ed 100644
--- a/rewatch/src/watcher.rs
+++ b/rewatch/src/watcher.rs
@@ -256,17 +256,17 @@ async fn async_watch(
                 return Ok(());
             }
 
-            // Detect rescript.json changes and trigger a full rebuild
-            if event
-                .paths
-                .iter()
-                .any(|p| p.file_name().map(|name| name == "rescript.json").unwrap_or(false))
-                && matches!(
-                    event.kind,
-                    EventKind::Modify(_) | EventKind::Create(_) | EventKind::Remove(_)
-                )
-            {
-                log::debug!("rescript.json changed -> full compile");
+            // Detect config-file changes and trigger a full rebuild.
+            // Legacy bsconfig.json is accepted for backward compatibility.
+            if event.paths.iter().any(|p| {
+                p.file_name()
+                    .map(|name| name == "rescript.json" || name == "bsconfig.json")
+                    .unwrap_or(false)
+            }) && matches!(
+                event.kind,
+                EventKind::Modify(_) | EventKind::Create(_) | EventKind::Remove(_)
+            ) {
+                log::debug!("config file changed -> full compile");
                 needs_compile_type = CompileType::Full;
                 continue;
             }
diff --git a/rewatch/tests/snapshots/clean-rebuild.txt b/rewatch/tests/snapshots/clean-rebuild.txt
index 5617126e645..5d6736b3b05 100644
--- a/rewatch/tests/snapshots/clean-rebuild.txt
+++ b/rewatch/tests/snapshots/clean-rebuild.txt
@@ -13,12 +13,21 @@ Compiled 430 modules
 
 
 
+Package '@testrepo/deprecated-config' uses deprecated config (support will be removed in a future version):
+  - field 'bs-dependencies' — use 'dependencies' instead
+  - field 'bs-dev-dependencies' — use 'dev-dependencies' instead
+  - field 'bsc-flags' — use 'compiler-flags' instead
+
 The field 'ignored-dirs' found in the package config of '@testrepo/deprecated-config' is not supported by ReScript 12's new build system.
 
 Unknown field 'some-new-field' found in the package config of '@testrepo/deprecated-config'. This option will be ignored.
 
-Unknown field 'bs-dependencies' found in the package config of '@testrepo/deprecated-config'. This option will be ignored.
-
-Unknown field 'bs-dev-dependencies' found in the package config of '@testrepo/deprecated-config'. This option will be ignored.
+Package 'rescript-nodejs' uses deprecated config (support will be removed in a future version):
+  - field 'bs-dependencies' — use 'dependencies' instead
+  - field 'bs-dev-dependencies' — use 'dev-dependencies' instead
+  - filename 'bsconfig.json' — rename to 'rescript.json'
+Please report this to the package maintainer: https://github.com/TheSpyder/rescript-nodejs/issues
 
-Unknown field 'bsc-flags' found in the package config of '@testrepo/deprecated-config'. This option will be ignored.
+Package 'sury' uses deprecated config (support will be removed in a future version):
+  - field 'bs-dev-dependencies' — use 'dev-dependencies' instead
+Please report this to the package maintainer: https://github.com/DZakh/sury/issues
diff --git a/rewatch/tests/snapshots/dependency-cycle.txt b/rewatch/tests/snapshots/dependency-cycle.txt
index 52fa210a123..eca324b9ed8 100644
--- a/rewatch/tests/snapshots/dependency-cycle.txt
+++ b/rewatch/tests/snapshots/dependency-cycle.txt
@@ -13,15 +13,24 @@ Compiled 1 modules
 
 
 
+Package '@testrepo/deprecated-config' uses deprecated config (support will be removed in a future version):
+  - field 'bs-dependencies' — use 'dependencies' instead
+  - field 'bs-dev-dependencies' — use 'dev-dependencies' instead
+  - field 'bsc-flags' — use 'compiler-flags' instead
+
 The field 'ignored-dirs' found in the package config of '@testrepo/deprecated-config' is not supported by ReScript 12's new build system.
 
 Unknown field 'some-new-field' found in the package config of '@testrepo/deprecated-config'. This option will be ignored.
 
-Unknown field 'bs-dependencies' found in the package config of '@testrepo/deprecated-config'. This option will be ignored.
-
-Unknown field 'bs-dev-dependencies' found in the package config of '@testrepo/deprecated-config'. This option will be ignored.
+Package 'rescript-nodejs' uses deprecated config (support will be removed in a future version):
+  - field 'bs-dependencies' — use 'dependencies' instead
+  - field 'bs-dev-dependencies' — use 'dev-dependencies' instead
+  - filename 'bsconfig.json' — rename to 'rescript.json'
+Please report this to the package maintainer: https://github.com/TheSpyder/rescript-nodejs/issues
 
-Unknown field 'bsc-flags' found in the package config of '@testrepo/deprecated-config'. This option will be ignored.
+Package 'sury' uses deprecated config (support will be removed in a future version):
+  - field 'bs-dev-dependencies' — use 'dev-dependencies' instead
+Please report this to the package maintainer: https://github.com/DZakh/sury/issues
 
 Can't continue... Found a circular dependency in your code:
 Dep01 (packages/dep01/src/Dep01.res)
diff --git a/rewatch/tests/snapshots/dev-dependency-used-by-non-dev-source.txt b/rewatch/tests/snapshots/dev-dependency-used-by-non-dev-source.txt
index a8b6decdf2b..3f5bf7f5404 100644
--- a/rewatch/tests/snapshots/dev-dependency-used-by-non-dev-source.txt
+++ b/rewatch/tests/snapshots/dev-dependency-used-by-non-dev-source.txt
@@ -13,15 +13,24 @@ Compiled 2 modules
 
 
 
+Package '@testrepo/deprecated-config' uses deprecated config (support will be removed in a future version):
+  - field 'bs-dependencies' — use 'dependencies' instead
+  - field 'bs-dev-dependencies' — use 'dev-dependencies' instead
+  - field 'bsc-flags' — use 'compiler-flags' instead
+
 The field 'ignored-dirs' found in the package config of '@testrepo/deprecated-config' is not supported by ReScript 12's new build system.
 
 Unknown field 'some-new-field' found in the package config of '@testrepo/deprecated-config'. This option will be ignored.
 
-Unknown field 'bs-dependencies' found in the package config of '@testrepo/deprecated-config'. This option will be ignored.
-
-Unknown field 'bs-dev-dependencies' found in the package config of '@testrepo/deprecated-config'. This option will be ignored.
+Package 'rescript-nodejs' uses deprecated config (support will be removed in a future version):
+  - field 'bs-dependencies' — use 'dependencies' instead
+  - field 'bs-dev-dependencies' — use 'dev-dependencies' instead
+  - filename 'bsconfig.json' — rename to 'rescript.json'
+Please report this to the package maintainer: https://github.com/TheSpyder/rescript-nodejs/issues
 
-Unknown field 'bsc-flags' found in the package config of '@testrepo/deprecated-config'. This option will be ignored.
+Package 'sury' uses deprecated config (support will be removed in a future version):
+  - field 'bs-dev-dependencies' — use 'dev-dependencies' instead
+Please report this to the package maintainer: https://github.com/DZakh/sury/issues
 
   We've found a bug for you!
   /packages/with-dev-deps/src/FileToTest.res:2:6-11
diff --git a/rewatch/tests/snapshots/remove-file.txt b/rewatch/tests/snapshots/remove-file.txt
index 83dba834585..ff4d3970ac4 100644
--- a/rewatch/tests/snapshots/remove-file.txt
+++ b/rewatch/tests/snapshots/remove-file.txt
@@ -13,15 +13,24 @@ Compiled 2 modules
 
 
 
+Package '@testrepo/deprecated-config' uses deprecated config (support will be removed in a future version):
+  - field 'bs-dependencies' — use 'dependencies' instead
+  - field 'bs-dev-dependencies' — use 'dev-dependencies' instead
+  - field 'bsc-flags' — use 'compiler-flags' instead
+
 The field 'ignored-dirs' found in the package config of '@testrepo/deprecated-config' is not supported by ReScript 12's new build system.
 
 Unknown field 'some-new-field' found in the package config of '@testrepo/deprecated-config'. This option will be ignored.
 
-Unknown field 'bs-dependencies' found in the package config of '@testrepo/deprecated-config'. This option will be ignored.
-
-Unknown field 'bs-dev-dependencies' found in the package config of '@testrepo/deprecated-config'. This option will be ignored.
+Package 'rescript-nodejs' uses deprecated config (support will be removed in a future version):
+  - field 'bs-dependencies' — use 'dependencies' instead
+  - field 'bs-dev-dependencies' — use 'dev-dependencies' instead
+  - filename 'bsconfig.json' — rename to 'rescript.json'
+Please report this to the package maintainer: https://github.com/TheSpyder/rescript-nodejs/issues
 
-Unknown field 'bsc-flags' found in the package config of '@testrepo/deprecated-config'. This option will be ignored.
+Package 'sury' uses deprecated config (support will be removed in a future version):
+  - field 'bs-dev-dependencies' — use 'dev-dependencies' instead
+Please report this to the package maintainer: https://github.com/DZakh/sury/issues
 
   We've found a bug for you!
   /packages/dep01/src/Dep01.res:3:9-17
diff --git a/rewatch/tests/snapshots/rename-file-internal-dep-namespace.txt b/rewatch/tests/snapshots/rename-file-internal-dep-namespace.txt
index 2c67137b649..6e0311b7589 100644
--- a/rewatch/tests/snapshots/rename-file-internal-dep-namespace.txt
+++ b/rewatch/tests/snapshots/rename-file-internal-dep-namespace.txt
@@ -13,15 +13,24 @@ Compiled 3 modules
 
 
 
+Package '@testrepo/deprecated-config' uses deprecated config (support will be removed in a future version):
+  - field 'bs-dependencies' — use 'dependencies' instead
+  - field 'bs-dev-dependencies' — use 'dev-dependencies' instead
+  - field 'bsc-flags' — use 'compiler-flags' instead
+
 The field 'ignored-dirs' found in the package config of '@testrepo/deprecated-config' is not supported by ReScript 12's new build system.
 
 Unknown field 'some-new-field' found in the package config of '@testrepo/deprecated-config'. This option will be ignored.
 
-Unknown field 'bs-dependencies' found in the package config of '@testrepo/deprecated-config'. This option will be ignored.
-
-Unknown field 'bs-dev-dependencies' found in the package config of '@testrepo/deprecated-config'. This option will be ignored.
+Package 'rescript-nodejs' uses deprecated config (support will be removed in a future version):
+  - field 'bs-dependencies' — use 'dependencies' instead
+  - field 'bs-dev-dependencies' — use 'dev-dependencies' instead
+  - filename 'bsconfig.json' — rename to 'rescript.json'
+Please report this to the package maintainer: https://github.com/TheSpyder/rescript-nodejs/issues
 
-Unknown field 'bsc-flags' found in the package config of '@testrepo/deprecated-config'. This option will be ignored.
+Package 'sury' uses deprecated config (support will be removed in a future version):
+  - field 'bs-dev-dependencies' — use 'dev-dependencies' instead
+Please report this to the package maintainer: https://github.com/DZakh/sury/issues
 
   We've found a bug for you!
   /packages/new-namespace/src/NS_alias.res:2:1-16
diff --git a/rewatch/tests/snapshots/rename-file-internal-dep.txt b/rewatch/tests/snapshots/rename-file-internal-dep.txt
index d7982bdf5cc..68215bf2153 100644
--- a/rewatch/tests/snapshots/rename-file-internal-dep.txt
+++ b/rewatch/tests/snapshots/rename-file-internal-dep.txt
@@ -13,15 +13,24 @@ Compiled 3 modules
 
 
 
+Package '@testrepo/deprecated-config' uses deprecated config (support will be removed in a future version):
+  - field 'bs-dependencies' — use 'dependencies' instead
+  - field 'bs-dev-dependencies' — use 'dev-dependencies' instead
+  - field 'bsc-flags' — use 'compiler-flags' instead
+
 The field 'ignored-dirs' found in the package config of '@testrepo/deprecated-config' is not supported by ReScript 12's new build system.
 
 Unknown field 'some-new-field' found in the package config of '@testrepo/deprecated-config'. This option will be ignored.
 
-Unknown field 'bs-dependencies' found in the package config of '@testrepo/deprecated-config'. This option will be ignored.
-
-Unknown field 'bs-dev-dependencies' found in the package config of '@testrepo/deprecated-config'. This option will be ignored.
+Package 'rescript-nodejs' uses deprecated config (support will be removed in a future version):
+  - field 'bs-dependencies' — use 'dependencies' instead
+  - field 'bs-dev-dependencies' — use 'dev-dependencies' instead
+  - filename 'bsconfig.json' — rename to 'rescript.json'
+Please report this to the package maintainer: https://github.com/TheSpyder/rescript-nodejs/issues
 
-Unknown field 'bsc-flags' found in the package config of '@testrepo/deprecated-config'. This option will be ignored.
+Package 'sury' uses deprecated config (support will be removed in a future version):
+  - field 'bs-dev-dependencies' — use 'dev-dependencies' instead
+Please report this to the package maintainer: https://github.com/DZakh/sury/issues
 
   We've found a bug for you!
   /packages/main/src/Main.res:4:13-29
diff --git a/rewatch/tests/snapshots/rename-file-with-interface.txt b/rewatch/tests/snapshots/rename-file-with-interface.txt
index 2422e04f1ac..f26462d8151 100644
--- a/rewatch/tests/snapshots/rename-file-with-interface.txt
+++ b/rewatch/tests/snapshots/rename-file-with-interface.txt
@@ -14,12 +14,21 @@ Compiled 2 modules
 
 
 
+Package '@testrepo/deprecated-config' uses deprecated config (support will be removed in a future version):
+  - field 'bs-dependencies' — use 'dependencies' instead
+  - field 'bs-dev-dependencies' — use 'dev-dependencies' instead
+  - field 'bsc-flags' — use 'compiler-flags' instead
+
 The field 'ignored-dirs' found in the package config of '@testrepo/deprecated-config' is not supported by ReScript 12's new build system.
 
 Unknown field 'some-new-field' found in the package config of '@testrepo/deprecated-config'. This option will be ignored.
 
-Unknown field 'bs-dependencies' found in the package config of '@testrepo/deprecated-config'. This option will be ignored.
-
-Unknown field 'bs-dev-dependencies' found in the package config of '@testrepo/deprecated-config'. This option will be ignored.
+Package 'rescript-nodejs' uses deprecated config (support will be removed in a future version):
+  - field 'bs-dependencies' — use 'dependencies' instead
+  - field 'bs-dev-dependencies' — use 'dev-dependencies' instead
+  - filename 'bsconfig.json' — rename to 'rescript.json'
+Please report this to the package maintainer: https://github.com/TheSpyder/rescript-nodejs/issues
 
-Unknown field 'bsc-flags' found in the package config of '@testrepo/deprecated-config'. This option will be ignored.
+Package 'sury' uses deprecated config (support will be removed in a future version):
+  - field 'bs-dev-dependencies' — use 'dev-dependencies' instead
+Please report this to the package maintainer: https://github.com/DZakh/sury/issues
diff --git a/rewatch/tests/snapshots/rename-file.txt b/rewatch/tests/snapshots/rename-file.txt
index 2ce31e691c5..347bc002df3 100644
--- a/rewatch/tests/snapshots/rename-file.txt
+++ b/rewatch/tests/snapshots/rename-file.txt
@@ -13,12 +13,21 @@ Compiled 2 modules
 
 
 
+Package '@testrepo/deprecated-config' uses deprecated config (support will be removed in a future version):
+  - field 'bs-dependencies' — use 'dependencies' instead
+  - field 'bs-dev-dependencies' — use 'dev-dependencies' instead
+  - field 'bsc-flags' — use 'compiler-flags' instead
+
 The field 'ignored-dirs' found in the package config of '@testrepo/deprecated-config' is not supported by ReScript 12's new build system.
 
 Unknown field 'some-new-field' found in the package config of '@testrepo/deprecated-config'. This option will be ignored.
 
-Unknown field 'bs-dependencies' found in the package config of '@testrepo/deprecated-config'. This option will be ignored.
-
-Unknown field 'bs-dev-dependencies' found in the package config of '@testrepo/deprecated-config'. This option will be ignored.
+Package 'rescript-nodejs' uses deprecated config (support will be removed in a future version):
+  - field 'bs-dependencies' — use 'dependencies' instead
+  - field 'bs-dev-dependencies' — use 'dev-dependencies' instead
+  - filename 'bsconfig.json' — rename to 'rescript.json'
+Please report this to the package maintainer: https://github.com/TheSpyder/rescript-nodejs/issues
 
-Unknown field 'bsc-flags' found in the package config of '@testrepo/deprecated-config'. This option will be ignored.
+Package 'sury' uses deprecated config (support will be removed in a future version):
+  - field 'bs-dev-dependencies' — use 'dev-dependencies' instead
+Please report this to the package maintainer: https://github.com/DZakh/sury/issues
diff --git a/rewatch/tests/snapshots/rename-interface-file.txt b/rewatch/tests/snapshots/rename-interface-file.txt
index 9eb5e5bdd7e..b7c694c4c33 100644
--- a/rewatch/tests/snapshots/rename-interface-file.txt
+++ b/rewatch/tests/snapshots/rename-interface-file.txt
@@ -14,12 +14,21 @@ Compiled 2 modules
 
 
 
+Package '@testrepo/deprecated-config' uses deprecated config (support will be removed in a future version):
+  - field 'bs-dependencies' — use 'dependencies' instead
+  - field 'bs-dev-dependencies' — use 'dev-dependencies' instead
+  - field 'bsc-flags' — use 'compiler-flags' instead
+
 The field 'ignored-dirs' found in the package config of '@testrepo/deprecated-config' is not supported by ReScript 12's new build system.
 
 Unknown field 'some-new-field' found in the package config of '@testrepo/deprecated-config'. This option will be ignored.
 
-Unknown field 'bs-dependencies' found in the package config of '@testrepo/deprecated-config'. This option will be ignored.
-
-Unknown field 'bs-dev-dependencies' found in the package config of '@testrepo/deprecated-config'. This option will be ignored.
+Package 'rescript-nodejs' uses deprecated config (support will be removed in a future version):
+  - field 'bs-dependencies' — use 'dependencies' instead
+  - field 'bs-dev-dependencies' — use 'dev-dependencies' instead
+  - filename 'bsconfig.json' — rename to 'rescript.json'
+Please report this to the package maintainer: https://github.com/TheSpyder/rescript-nodejs/issues
 
-Unknown field 'bsc-flags' found in the package config of '@testrepo/deprecated-config'. This option will be ignored.
+Package 'sury' uses deprecated config (support will be removed in a future version):
+  - field 'bs-dev-dependencies' — use 'dev-dependencies' instead
+Please report this to the package maintainer: https://github.com/DZakh/sury/issues
diff --git a/rewatch/tests/suite.sh b/rewatch/tests/suite.sh
index b7f6bee6146..613b291d111 100755
--- a/rewatch/tests/suite.sh
+++ b/rewatch/tests/suite.sh
@@ -38,7 +38,7 @@ fi
 success "No stale rescript processes found"
 
 bold "Yarn install"
-(cd ../testrepo && yarn && cp node_modules/rescript-nodejs/bsconfig.json node_modules/rescript-nodejs/rescript.json)
+(cd ../testrepo && yarn)
 
 bold "Rescript version"
 (cd ../testrepo && ./node_modules/.bin/rescript --version)
diff --git a/tests/build_tests/warn_legacy_config/input.js b/tests/build_tests/warn_legacy_config/input.js
index 86d93077707..364541af502 100644
--- a/tests/build_tests/warn_legacy_config/input.js
+++ b/tests/build_tests/warn_legacy_config/input.js
@@ -6,6 +6,10 @@ import { setup } from "#dev/process";
 const { execBuild, execClean } = setup(import.meta.dirname);
 
 const output = await execBuild();
-assert.notEqual(output.status, 0);
-assert.match(output.stderr, /could not read rescript\.json/i);
+assert.equal(output.status, 0);
+assert.match(output.stderr, /uses deprecated config/i);
+assert.match(
+  output.stderr,
+  /filename 'bsconfig\.json' .* rename to 'rescript\.json'/i,
+);
 await execClean();