diff --git a/Cargo.lock b/Cargo.lock
index a493f322a57..cdc026359c1 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -108,6 +108,12 @@ dependencies = [
  "vec_map",
 ]
 
+[[package]]
+name = "const_fn"
+version = "0.4.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "cd51eab21ab4fd6a3bf889e2d0958c0a6e3a61ad04260325e919e652a2a62826"
+
 [[package]]
 name = "crc32fast"
 version = "1.2.1"
@@ -117,6 +123,58 @@ dependencies = [
  "cfg-if 1.0.0",
 ]
 
+[[package]]
+name = "crossbeam-channel"
+version = "0.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "dca26ee1f8d361640700bde38b2c37d8c22b3ce2d360e1fc1c74ea4b0aa7d775"
+dependencies = [
+ "cfg-if 1.0.0",
+ "crossbeam-utils",
+]
+
+[[package]]
+name = "crossbeam-deque"
+version = "0.8.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "94af6efb46fef72616855b036a624cf27ba656ffc9be1b9a3c931cfc7749a9a9"
+dependencies = [
+ "cfg-if 1.0.0",
+ "crossbeam-epoch",
+ "crossbeam-utils",
+]
+
+[[package]]
+name = "crossbeam-epoch"
+version = "0.9.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a1aaa739f95311c2c7887a76863f500026092fb1dce0161dab577e559ef3569d"
+dependencies = [
+ "cfg-if 1.0.0",
+ "const_fn",
+ "crossbeam-utils",
+ "lazy_static",
+ "memoffset",
+ "scopeguard",
+]
+
+[[package]]
+name = "crossbeam-utils"
+version = "0.8.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "02d96d1e189ef58269ebe5b97953da3274d83a93af647c2ddd6f9dab28cedb8d"
+dependencies = [
+ "autocfg",
+ "cfg-if 1.0.0",
+ "lazy_static",
+]
+
+[[package]]
+name = "either"
+version = "1.6.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e78d4f1cc4ae33bbfc157ed5d5a5ef3bc29227303d595861deb238fcec4e9457"
+
 [[package]]
 name = "flate2"
 version = "1.0.19"
@@ -206,6 +264,15 @@ version = "2.3.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "0ee1c47aaa256ecabcaea351eae4a9b01ef39ed810004e298d2511ed284b1525"
 
+[[package]]
+name = "memoffset"
+version = "0.6.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "157b4208e3059a8f9e78d559edc658e13df41410cb3ae03979c83130067fdd87"
+dependencies = [
+ "autocfg",
+]
+
 [[package]]
 name = "miniz_oxide"
 version = "0.4.3"
@@ -243,6 +310,16 @@ dependencies = [
  "autocfg",
 ]
 
+[[package]]
+name = "num_cpus"
+version = "1.13.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "05499f3756671c15885fee9034446956fff3f243d6077b91e5767df161f766b3"
+dependencies = [
+ "hermit-abi",
+ "libc",
+]
+
 [[package]]
 name = "pin-project-lite"
 version = "0.2.0"
@@ -267,6 +344,31 @@ dependencies = [
  "proc-macro2",
 ]
 
+[[package]]
+name = "rayon"
+version = "1.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8b0d8e0819fadc20c74ea8373106ead0600e3a67ef1fe8da56e39b9ae7275674"
+dependencies = [
+ "autocfg",
+ "crossbeam-deque",
+ "either",
+ "rayon-core",
+]
+
+[[package]]
+name = "rayon-core"
+version = "1.9.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9ab346ac5921dc62ffa9f89b7a773907511cdfa5490c572ae9be1be33e8afa4a"
+dependencies = [
+ "crossbeam-channel",
+ "crossbeam-deque",
+ "crossbeam-utils",
+ "lazy_static",
+ "num_cpus",
+]
+
 [[package]]
 name = "regex"
 version = "1.4.2"
@@ -302,6 +404,8 @@ dependencies = [
  "clap",
  "flate2",
  "node-types",
+ "num_cpus",
+ "rayon",
  "tracing",
  "tracing-subscriber",
  "tree-sitter",
@@ -339,6 +443,12 @@ version = "1.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ea6a9290e3c9cf0f18145ef7ffa62d68ee0bf5fcd651017e586dc7fd5da448c2"
 
+[[package]]
+name = "scopeguard"
+version = "1.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d29ab0c6d3fc0ee92fe66e2d99f700eab17a8d57d1c1d3b748380fb20baa78cd"
+
 [[package]]
 name = "semver"
 version = "0.9.0"
diff --git a/extractor/Cargo.toml b/extractor/Cargo.toml
index 180e767b53b..5d98f99bebe 100644
--- a/extractor/Cargo.toml
+++ b/extractor/Cargo.toml
@@ -14,3 +14,5 @@ tree-sitter-ruby = { git = "https://github.com/tree-sitter/tree-sitter-ruby.git"
 clap = "2.33"
 tracing = "0.1"
 tracing-subscriber = { version = "0.2", features = ["env-filter"] }
+rayon = "1.5.0"
+num_cpus = "1.13.0"
diff --git a/extractor/src/extractor.rs b/extractor/src/extractor.rs
index 11d101bd653..dcd762e43cb 100644
--- a/extractor/src/extractor.rs
+++ b/extractor/src/extractor.rs
@@ -4,7 +4,7 @@ use std::collections::BTreeSet as Set;
 use std::fmt;
 use std::path::Path;
 use tracing::{error, info, span, Level};
-use tree_sitter::{Language, Node, Parser, Tree};
+use tree_sitter::{Node, Parser, Tree};
 
 struct TrapWriter {
     /// The accumulated trap entries
@@ -148,55 +148,38 @@ impl TrapWriter {
     }
 }
 
-pub struct Extractor {
-    pub parser: Parser,
-    pub schema: NodeTypeMap,
-}
+/// Extracts the source file at `path`, which is assumed to be canonicalized.
+pub fn extract(parser: &mut Parser, schema: &NodeTypeMap, path: &Path) -> std::io::Result<Program> {
+    let span = span!(
+        Level::TRACE,
+        "extract",
+        file = %path.display()
+    );
 
-pub fn create(language: Language, schema: NodeTypeMap) -> Extractor {
-    let mut parser = Parser::new();
-    parser.set_language(language).unwrap();
+    let _enter = span.enter();
 
-    Extractor { parser, schema }
-}
+    info!("extracting: {}", path.display());
 
-impl Extractor {
-    /// Extracts the source file at `path`, which is assumed to be canonicalized.
-    pub fn extract<'a>(&'a mut self, path: &Path) -> std::io::Result<Program> {
-        let span = span!(
-            Level::TRACE,
-            "extract",
-            file = %path.display()
-        );
+    let source = std::fs::read(&path)?;
+    let tree = parser.parse(&source, None).expect("Failed to parse file");
+    let mut trap_writer = new_trap_writer();
+    trap_writer.comment(format!("Auto-generated TRAP file for {}", path.display()));
+    let file_label = &trap_writer.populate_file(path);
+    let mut visitor = Visitor {
+        source: &source,
+        trap_writer: trap_writer,
+        // TODO: should we handle path strings that are not valid UTF8 better?
+        path: format!("{}", path.display()),
+        file_label: *file_label,
+        token_counter: 0,
+        toplevel_child_counter: 0,
+        stack: Vec::new(),
+        schema,
+    };
+    traverse(&tree, &mut visitor);
 
-        let _enter = span.enter();
-
-        info!("extracting: {}", path.display());
-
-        let source = std::fs::read(&path)?;
-        let tree = &self
-            .parser
-            .parse(&source, None)
-            .expect("Failed to parse file");
-        let mut trap_writer = new_trap_writer();
-        trap_writer.comment(format!("Auto-generated TRAP file for {}", path.display()));
-        let file_label = &trap_writer.populate_file(path);
-        let mut visitor = Visitor {
-            source: &source,
-            trap_writer: trap_writer,
-            // TODO: should we handle path strings that are not valid UTF8 better?
-            path: format!("{}", path.display()),
-            file_label: *file_label,
-            token_counter: 0,
-            toplevel_child_counter: 0,
-            stack: Vec::new(),
-            schema: &self.schema,
-        };
-        traverse(&tree, &mut visitor);
-
-        &self.parser.reset();
-        Ok(Program(visitor.trap_writer.trap_output))
-    }
+    parser.reset();
+    Ok(Program(visitor.trap_writer.trap_output))
 }
 
 /// Normalizes the path according the common CodeQL specification. Assumes that
diff --git a/extractor/src/main.rs b/extractor/src/main.rs
index ca9747fb673..abcb1871dfe 100644
--- a/extractor/src/main.rs
+++ b/extractor/src/main.rs
@@ -1,10 +1,14 @@
 mod extractor;
 
+extern crate num_cpus;
+
 use clap;
 use flate2::write::GzEncoder;
+use rayon::prelude::*;
 use std::fs;
 use std::io::{BufRead, BufWriter, Write};
 use std::path::{Path, PathBuf};
+use tree_sitter::Parser;
 
 enum TrapCompression {
     None,
@@ -42,6 +46,41 @@ impl TrapCompression {
     }
 }
 
+/**
+ * Gets the number of threads the extractor should use, by reading the
+ * CODEQL_THREADS environment variable and using it as follows:
+ *
+ * If the number is positive, it indicates the number of threads that should be
+ * used. If the number is negative or zero, it should be added to the number of
+ * cores available on the machine to determine how many threads to use (minimum
+ * of 1). If unspecified, should be considered as set to 1.
+ */
+fn num_codeql_threads() -> usize {
+    match std::env::var("CODEQL_THREADS") {
+        Ok(num) => match num.parse::<i32>() {
+            Ok(num) => {
+                if num <= 0 {
+                    let reduction = -num as usize;
+                    num_cpus::get() - reduction
+                } else {
+                    num as usize
+                }
+            }
+
+            Err(_) => {
+                tracing::error!(
+                    "Unable to parse CODEQL_THREADS value '{}'; defaulting to 1 thread.",
+                    &num
+                );
+                1
+            }
+        },
+
+        // Use 1 thread if the environment variable isn't set.
+        Err(_) => 1,
+    }
+}
+
 fn main() -> std::io::Result<()> {
     tracing_subscriber::fmt()
         .with_target(false)
@@ -50,6 +89,21 @@ fn main() -> std::io::Result<()> {
         .with_env_filter(tracing_subscriber::EnvFilter::from_default_env())
         .init();
 
+    let num_threads = num_codeql_threads();
+    tracing::info!(
+        "Using {} {}",
+        num_threads,
+        if num_threads == 1 {
+            "thread"
+        } else {
+            "threads"
+        }
+    );
+    rayon::ThreadPoolBuilder::new()
+        .num_threads(num_threads)
+        .build_global()
+        .unwrap();
+
     let matches = clap::App::new("Ruby extractor")
         .version("1.0")
         .author("GitHub")
@@ -76,12 +130,15 @@ fn main() -> std::io::Result<()> {
 
     let language = tree_sitter_ruby::language();
     let schema = node_types::read_node_types_str(tree_sitter_ruby::NODE_TYPES)?;
-    let mut extractor = extractor::create(language, schema);
-    for line in std::io::BufReader::new(file_list).lines() {
-        let path = PathBuf::from(line?).canonicalize()?;
+    let lines: std::io::Result<Vec<String>> = std::io::BufReader::new(file_list).lines().collect();
+    let lines = lines?;
+    lines.par_iter().try_for_each(|line| {
+        let mut parser = Parser::new();
+        parser.set_language(language).unwrap();
+        let path = PathBuf::from(line).canonicalize()?;
         let trap_file = path_for(&trap_dir, &path, trap_compression.extension());
         let src_archive_file = path_for(&src_archive_dir, &path, "");
-        let trap = extractor.extract(&path)?;
+        let trap = extractor::extract(&mut parser, &schema, &path)?;
         std::fs::create_dir_all(&src_archive_file.parent().unwrap())?;
         std::fs::copy(&path, &src_archive_file)?;
         std::fs::create_dir_all(&trap_file.parent().unwrap())?;
@@ -96,8 +153,10 @@ fn main() -> std::io::Result<()> {
                 write!(compressed_writer, "{}", trap)?;
             }
         }
-    }
-    return Ok(());
+        std::io::Result::Ok(())
+    })?;
+
+    Ok(())
 }
 
 fn path_for(dir: &Path, path: &Path, ext: &str) -> PathBuf {