diff --git a/core/core-projects.el b/core/core-projects.el
index 4fa345b29..d14505f51 100644
--- a/core/core-projects.el
+++ b/core/core-projects.el
@@ -48,8 +48,27 @@ Emacs.")
   :config
   (projectile-mode +1)
 
+  ;; In the interest of performance, we reduce the number of project root marker
+  ;; files/directories projectile searches for when resolving the project root.
+  (setq projectile-project-root-files-bottom-up
+        (append '(".project"     ; doom project marker
+                  ".git")        ; Git VCS root dir
+                (when (executable-find "hg")
+                  '(".hg"))      ; Mercurial VCS root dir
+                (when (executable-find "fossil")
+                  '(".fslckout"  ; Fossil VCS root dir
+                    "_FOSSIL_")) ; Fossil VCS root DB on Windows
+                (when (executable-find "bzr")
+                  '(".bzr"))     ; Bazaar VCS root dir
+                (when (executable-find "darcs")
+                  '("_darcs")))  ; Darcs VCS root dir
+        ;; This will be filled by other modules. We build this list manually so
+        ;; projectile doesn't perform so many file checks every time it resolves
+        ;; a project's root -- particularly when a file has no project.
+        projectile-project-root-files '("TAGS")
+        projectile-project-root-files-top-down-recurring '(".svn" "Makefile"))
+
   ;; a more generic project root file
-  (push ".project" projectile-project-root-files-bottom-up)
   (push (abbreviate-file-name doom-local-dir) projectile-globally-ignored-directories)
 
   ;; Disable commands that won't work, as is, and that Doom already provides a
diff --git a/modules/lang/clojure/config.el b/modules/lang/clojure/config.el
index 1f28e3290..3da3d0ab6 100644
--- a/modules/lang/clojure/config.el
+++ b/modules/lang/clojure/config.el
@@ -1,5 +1,12 @@
 ;;; lang/clojure/config.el -*- lexical-binding: t; -*-
 
+(after! projectile
+  (pushnew! projectile-project-root-files "project.clj" "build.boot" "deps.edn"))
+
+
+;;
+;;; Packages
+
 ;;;###package clojure-mode
 (add-hook 'clojure-mode-hook #'rainbow-delimiters-mode)
 
diff --git a/modules/lang/elixir/config.el b/modules/lang/elixir/config.el
index 04d78ad5f..ce19d9e1d 100644
--- a/modules/lang/elixir/config.el
+++ b/modules/lang/elixir/config.el
@@ -1,5 +1,12 @@
 ;;; lang/elixir/config.el -*- lexical-binding: t; -*-
 
+(after! projectile
+  (add-to-list 'projectile-project-root-files "mix.exs"))
+
+
+;;
+;;; Packages
+
 (use-package! elixir-mode
   :defer t
   :init
diff --git a/modules/lang/ess/config.el b/modules/lang/ess/config.el
index 1041a5130..8bdccc198 100644
--- a/modules/lang/ess/config.el
+++ b/modules/lang/ess/config.el
@@ -1,5 +1,12 @@
 ;;; lang/ess/config.el -*- lexical-binding: t; -*-
 
+(after! projectile
+  (add-to-list 'projectile-project-root-files "DESCRIPTION"))
+
+
+;;
+;;; Packages
+
 (use-package! ess
   :commands stata SAS
   :init
diff --git a/modules/lang/haskell/config.el b/modules/lang/haskell/config.el
index c427f5b64..4ed768074 100644
--- a/modules/lang/haskell/config.el
+++ b/modules/lang/haskell/config.el
@@ -1,5 +1,8 @@
 ;;; lang/haskell/config.el -*- lexical-binding: t; -*-
 
+(after! projectile
+  (add-to-list 'projectile-project-root-files "stack.yaml"))
+
 (cond ((featurep! +intero) (load! "+intero"))
       ((featurep! +dante)  (load! "+dante"))
       ((featurep! +lsp)    (load! "+lsp")))
diff --git a/modules/lang/java/config.el b/modules/lang/java/config.el
index ed9ee04d0..e4818df76 100644
--- a/modules/lang/java/config.el
+++ b/modules/lang/java/config.el
@@ -17,6 +17,9 @@ If the depth is 1, the first directory in src/java/net/lissner/game/MyClass.java
   is removed: java.net.lissner.game.
 If the depth is 2, the first two directories are removed: net.lissner.game.")
 
+(after! projectile
+  (pushnew! projectile-project-root-files "gradlew" "build.gradle"))
+
 
 ;;
 ;; java-mode
diff --git a/modules/lang/php/config.el b/modules/lang/php/config.el
index d06e9f271..d3b34bd35 100644
--- a/modules/lang/php/config.el
+++ b/modules/lang/php/config.el
@@ -1,5 +1,12 @@
 ;;; lang/php/config.el -*- lexical-binding: t; -*-
 
+(after! projectile
+  (add-to-list 'projectile-project-root-files "composer.json"))
+
+
+;;
+;;; Packages
+
 (use-package! php-mode
   :mode "\\.inc\\'"
   :config
diff --git a/modules/lang/python/config.el b/modules/lang/python/config.el
index b26030bf0..16388d4d0 100644
--- a/modules/lang/python/config.el
+++ b/modules/lang/python/config.el
@@ -8,6 +8,9 @@ called.")
   "CLI arguments to initialize 'jupiter console %s' with when
 `+python/open-ipython-repl' is called.")
 
+(after! projectile
+  (pushnew! projectile-project-root-files "setup.py" "requirements.txt"))
+
 
 ;;
 ;; Packages
diff --git a/modules/lang/racket/config.el b/modules/lang/racket/config.el
index 5145a3e92..86b18e2aa 100644
--- a/modules/lang/racket/config.el
+++ b/modules/lang/racket/config.el
@@ -1,5 +1,12 @@
 ;;; lang/racket/config.el -*- lexical-binding: t; -*-
 
+(after! projectile
+  (add-to-list 'projectile-project-root-files "info.rkt"))
+
+
+;;
+;;; Packages
+
 (use-package! racket-mode
   :hook (racket-repl-mode . racket-unicode-input-method-enable)
   :config
diff --git a/modules/lang/ruby/config.el b/modules/lang/ruby/config.el
index c0ed30115..a42de9b24 100644
--- a/modules/lang/ruby/config.el
+++ b/modules/lang/ruby/config.el
@@ -1,5 +1,9 @@
 ;;; lang/ruby/config.el -*- lexical-binding: t; -*-
 
+(after! projectile
+  (add-to-list 'projectile-project-root-files "Gemfile"))
+
+
 ;;
 ;;; Packages
 
diff --git a/modules/lang/rust/config.el b/modules/lang/rust/config.el
index 671e6e24b..c7f00538d 100644
--- a/modules/lang/rust/config.el
+++ b/modules/lang/rust/config.el
@@ -1,5 +1,12 @@
 ;;; lang/rust/config.el -*- lexical-binding: t; -*-
 
+(after! projectile
+  (add-to-list 'projectile-project-root-files "Cargo.toml"))
+
+
+;;
+;;; Packages
+
 (use-package! rust-mode
   :defer t
   :config
diff --git a/modules/lang/scala/config.el b/modules/lang/scala/config.el
index 4d4dcb099..4a81fedd9 100644
--- a/modules/lang/scala/config.el
+++ b/modules/lang/scala/config.el
@@ -1,5 +1,12 @@
 ;;; lang/scala/config.el -*- lexical-binding: t; -*-
 
+(after! projectile
+  (add-to-list 'projectile-project-root-files "build.sbt"))
+
+
+;;
+;;; Packages
+
 (after! scala-mode
   (setq scala-indent:align-parameters t
         ;; indent block comments to first asterix, not second