diff --git a/src/commands/sourcemaps/inject.rs b/src/commands/sourcemaps/inject.rs
new file mode 100644
index 0000000000..d126d2b446
--- /dev/null
+++ b/src/commands/sourcemaps/inject.rs
@@ -0,0 +1,144 @@
+use std::fs::{self, File};
+use std::io::{Seek, Write};
+use std::path::{Path, PathBuf};
+
+use anyhow::{bail, Context, Result};
+use clap::{Arg, ArgMatches, Command};
+use glob::glob;
+use log::{debug, warn};
+use serde_json::Value;
+use symbolic::debuginfo::js;
+use uuid::Uuid;
+
+const CODE_SNIPPET_TEMPLATE: &str = r#"!function(){try{var e="undefined"!=typeof window?window:"undefined"!=typeof global?global:"undefined"!=typeof self?self:{},n=(new Error).stack;n&&(e._sentryDebugIds=e._sentryDebugIds||{},e._sentryDebugIds[n]="__SENTRY_DEBUG_ID__")}catch(e){}}()"#;
+const DEBUGID_PLACEHOLDER: &str = "__SENTRY_DEBUG_ID__";
+const SOURCEMAP_DEBUGID_KEY: &str = "debug_id";
+const DEBUGID_COMMENT_PREFIX: &str = "//# debugId";
+
+pub fn make_command(command: Command) -> Command {
+    command
+        .about("Fixes up JavaScript source files and sourcemaps with debug ids.")
+        .long_about(
+            "Fixes up JavaScript source files and sourcemaps with debug ids.{n}{n}\
+            For every JS source file that references a sourcemap, a debug id is generated and \
+            inserted into both files. If the referenced sourcemap already contains a debug id, \
+            that id is used instead.",
+        )
+        .arg(
+            Arg::new("path")
+                .value_name("PATH")
+                .required(true)
+                .help("The path or glob to the javascript files."),
+        )
+        .hide(true)
+}
+
+pub fn execute(matches: &ArgMatches) -> Result<()> {
+    let path = matches.get_one::<String>("path").unwrap();
+
+    let collected_paths: Vec<PathBuf> = glob(path)
+        .unwrap()
+        .flatten()
+        .filter(|path| path.extension().map_or(false, |ext| ext == "js"))
+        .collect();
+
+    if collected_paths.is_empty() {
+        warn!("Did not match any JavaScript files for pattern: {}", path);
+        return Ok(());
+    }
+
+    fixup_files(&collected_paths)
+}
+
+fn fixup_files(paths: &[PathBuf]) -> Result<()> {
+    for path in paths {
+        let js_path = path.as_path();
+
+        debug!("Processing js file {}", js_path.display());
+
+        let file =
+            fs::read_to_string(js_path).context(format!("Failed to open {}", js_path.display()))?;
+
+        if js::discover_debug_id(&file).is_some() {
+            debug!("File {} was previously processed", js_path.display());
+            continue;
+        }
+
+        let Some(sourcemap_url) = js::discover_sourcemaps_location(&file) else {
+            debug!("File {} does not contain a sourcemap url", js_path.display());
+            continue;
+        };
+
+        let sourcemap_path = js_path.with_file_name(sourcemap_url);
+
+        if !sourcemap_path.exists() {
+            warn!("Sourcemap file {} not found", sourcemap_path.display());
+            continue;
+        }
+
+        let debug_id = fixup_sourcemap(&sourcemap_path)
+            .context(format!("Failed to process {}", sourcemap_path.display()))?;
+
+        fixup_js_file(js_path, debug_id)
+            .context(format!("Failed to process {}", js_path.display()))?;
+    }
+
+    Ok(())
+}
+
+/// Appends the following text to a file:
+/// ```
+///
+/// <CODE_SNIPPET>[<debug_id>]
+/// //# sentryDebugId=<debug_id>
+///```
+/// where `<CODE_SNIPPET>[<debug_id>]`
+/// is `CODE_SNIPPET_TEMPLATE` with `debug_id` substituted for the `__SENTRY_DEBUG_ID__`
+/// placeholder.
+fn fixup_js_file(js_path: &Path, debug_id: Uuid) -> Result<()> {
+    let mut js_file = File::options().append(true).open(js_path)?;
+    let to_inject =
+        CODE_SNIPPET_TEMPLATE.replace(DEBUGID_PLACEHOLDER, &debug_id.hyphenated().to_string());
+    writeln!(js_file)?;
+    writeln!(js_file, "{to_inject}")?;
+    write!(js_file, "{DEBUGID_COMMENT_PREFIX}={debug_id}")?;
+
+    Ok(())
+}
+
+/// Fixes up a sourcemap file with a debug id.
+///
+/// If the file already contains a debug id under the `debugID` key, it is left unmodified.
+/// Otherwise, a fresh debug id is inserted under that key.
+///
+/// In either case, the value of the `debugID` key is returned.
+fn fixup_sourcemap(sourcemap_path: &Path) -> Result<Uuid> {
+    let mut sourcemap_file = File::options()
+        .read(true)
+        .write(true)
+        .open(sourcemap_path)?;
+    let mut sourcemap: Value = serde_json::from_reader(&sourcemap_file)?;
+
+    sourcemap_file.rewind()?;
+
+    let Some(map) = sourcemap.as_object_mut() else {
+        bail!("Invalid sourcemap");
+    };
+
+    match map.get(SOURCEMAP_DEBUGID_KEY) {
+        Some(id) => {
+            let debug_id = serde_json::from_value(id.clone())?;
+            debug!("Sourcemap already has a debug id");
+            Ok(debug_id)
+        }
+
+        None => {
+            let debug_id = Uuid::new_v4();
+            let id = serde_json::to_value(debug_id)?;
+            map.insert(SOURCEMAP_DEBUGID_KEY.to_string(), id);
+
+            serde_json::to_writer(&mut sourcemap_file, &sourcemap)?;
+            Ok(debug_id)
+        }
+    }
+}
diff --git a/src/commands/sourcemaps/mod.rs b/src/commands/sourcemaps/mod.rs
index 2407763e89..b37f3b3601 100644
--- a/src/commands/sourcemaps/mod.rs
+++ b/src/commands/sourcemaps/mod.rs
@@ -4,12 +4,14 @@ use clap::{ArgMatches, Command};
 use crate::utils::args::ArgExt;
 
 pub mod explain;
+pub mod inject;
 pub mod resolve;
 pub mod upload;
 
 macro_rules! each_subcommand {
     ($mac:ident) => {
         $mac!(explain);
+        $mac!(inject);
         $mac!(resolve);
         $mac!(upload);
     };
diff --git a/tests/integration/_cases/sourcemaps/sourcemaps-inject-help.trycmd b/tests/integration/_cases/sourcemaps/sourcemaps-inject-help.trycmd
new file mode 100644
index 0000000000..867762db1b
--- /dev/null
+++ b/tests/integration/_cases/sourcemaps/sourcemaps-inject-help.trycmd
@@ -0,0 +1,46 @@
+```
+$ sentry-cli[EXE] sourcemaps inject --help
+? success
+Fixes up JavaScript source files and sourcemaps with debug ids.
+
+For every JS source file that references a sourcemap, a debug id is generated and inserted into both
+files. If the referenced sourcemap already contains a debug id, that id is used instead.
+
+Usage: sentry-cli[EXE] sourcemaps inject [OPTIONS] <PATH>
+
+Arguments:
+  <PATH>
+          The path or glob to the javascript files.
+
+Options:
+  -o, --org <ORG>
+          The organization slug
+
+      --header <KEY:VALUE>
+          Custom headers that should be attached to all requests
+          in key:value format.
+
+  -p, --project <PROJECT>
+          The project slug.
+
+      --auth-token <AUTH_TOKEN>
+          Use the given Sentry auth token.
+
+  -r, --release <RELEASE>
+          The release slug.
+
+      --log-level <LOG_LEVEL>
+          Set the log output verbosity.
+          
+          [possible values: trace, debug, info, warn, error]
+
+      --quiet
+          Do not print any output while preserving correct exit code. This flag is currently
+          implemented only for selected subcommands.
+          
+          [aliases: silent]
+
+  -h, --help
+          Print help (see a summary with '-h')
+
+```
\ No newline at end of file
diff --git a/tests/integration/sourcemaps/inject.rs b/tests/integration/sourcemaps/inject.rs
new file mode 100644
index 0000000000..a4eafc2abb
--- /dev/null
+++ b/tests/integration/sourcemaps/inject.rs
@@ -0,0 +1,6 @@
+use crate::integration::register_test;
+
+#[test]
+fn command_sourcemaps_inject_help() {
+    register_test("sourcemaps/sourcemaps-inject-help.trycmd");
+}
diff --git a/tests/integration/sourcemaps/mod.rs b/tests/integration/sourcemaps/mod.rs
index c2c374da5c..5e1a263042 100644
--- a/tests/integration/sourcemaps/mod.rs
+++ b/tests/integration/sourcemaps/mod.rs
@@ -1,6 +1,7 @@
 use crate::integration::register_test;
 
 mod explain;
+mod inject;
 mod resolve;
 mod upload;