diff --git a/cli/format.go b/cli/format.go
index d057600b..7218a956 100644
--- a/cli/format.go
+++ b/cli/format.go
@@ -11,6 +11,7 @@ import (
 	"runtime"
 	"runtime/pprof"
 	"syscall"
+	"time"
 
 	"git.numtide.com/numtide/treefmt/format"
 	"git.numtide.com/numtide/treefmt/stats"
@@ -389,20 +390,26 @@ func (f *Format) detectFormatted(ctx context.Context) func() error {
 					return nil
 				}
 
-				// look up current file info
-				currentInfo, err := os.Stat(file.Path)
+				// check if the file has changed
+				changed, newInfo, err := file.HasChanged()
 				if err != nil {
-					return fmt.Errorf("failed to stat processed file: %w", err)
+					return err
 				}
 
-				// check if the file has changed
-				if !(file.Info.ModTime() == currentInfo.ModTime() && file.Info.Size() == currentInfo.Size()) {
+				if changed {
 					// record the change
 					stats.Add(stats.Formatted, 1)
 					// log the change for diagnostics
-					log.Debugf("file has been changed: %s", file.Path)
+					log.Debug(
+						"file has changed",
+						"path", file.Path,
+						"prev_size", file.Info.Size(),
+						"current_size", newInfo.Size(),
+						"prev_mod_time", file.Info.ModTime().Truncate(time.Second),
+						"current_mod_time", newInfo.ModTime().Truncate(time.Second),
+					)
 					// update the file info
-					file.Info = currentInfo
+					file.Info = newInfo
 				}
 
 				// mark as processed
diff --git a/cli/format_test.go b/cli/format_test.go
index 889926e8..1d6d75dd 100644
--- a/cli/format_test.go
+++ b/cli/format_test.go
@@ -9,6 +9,7 @@ import (
 	"path/filepath"
 	"regexp"
 	"testing"
+	"time"
 
 	"git.numtide.com/numtide/treefmt/config"
 	"git.numtide.com/numtide/treefmt/format"
@@ -159,22 +160,22 @@ func TestSpecifyingFormatters(t *testing.T) {
 	setup()
 	_, err := cmd(t, "-c", "--config-file", configPath, "--tree-root", tempDir)
 	as.NoError(err)
-	assertStats(t, as, 31, 31, 3, 3)
+	assertStats(t, as, 32, 32, 3, 3)
 
 	setup()
 	_, err = cmd(t, "-c", "--config-file", configPath, "--tree-root", tempDir, "--formatters", "elm,nix")
 	as.NoError(err)
-	assertStats(t, as, 31, 31, 2, 2)
+	assertStats(t, as, 32, 32, 2, 2)
 
 	setup()
 	_, err = cmd(t, "-c", "--config-file", configPath, "--tree-root", tempDir, "-f", "ruby,nix")
 	as.NoError(err)
-	assertStats(t, as, 31, 31, 2, 2)
+	assertStats(t, as, 32, 32, 2, 2)
 
 	setup()
 	_, err = cmd(t, "-c", "--config-file", configPath, "--tree-root", tempDir, "--formatters", "nix")
 	as.NoError(err)
-	assertStats(t, as, 31, 31, 1, 1)
+	assertStats(t, as, 32, 32, 1, 1)
 
 	// test bad names
 	setup()
@@ -204,7 +205,7 @@ func TestIncludesAndExcludes(t *testing.T) {
 	test.WriteConfig(t, configPath, cfg)
 	_, err := cmd(t, "-c", "--config-file", configPath, "--tree-root", tempDir)
 	as.NoError(err)
-	assertStats(t, as, 31, 31, 31, 0)
+	assertStats(t, as, 32, 32, 32, 0)
 
 	// globally exclude nix files
 	cfg.Global.Excludes = []string{"*.nix"}
@@ -212,7 +213,7 @@ func TestIncludesAndExcludes(t *testing.T) {
 	test.WriteConfig(t, configPath, cfg)
 	_, err = cmd(t, "-c", "--config-file", configPath, "--tree-root", tempDir)
 	as.NoError(err)
-	assertStats(t, as, 31, 31, 30, 0)
+	assertStats(t, as, 32, 32, 31, 0)
 
 	// add haskell files to the global exclude
 	cfg.Global.Excludes = []string{"*.nix", "*.hs"}
@@ -220,7 +221,7 @@ func TestIncludesAndExcludes(t *testing.T) {
 	test.WriteConfig(t, configPath, cfg)
 	_, err = cmd(t, "-c", "--config-file", configPath, "--tree-root", tempDir)
 	as.NoError(err)
-	assertStats(t, as, 31, 31, 24, 0)
+	assertStats(t, as, 32, 32, 25, 0)
 
 	echo := cfg.Formatters["echo"]
 
@@ -230,7 +231,7 @@ func TestIncludesAndExcludes(t *testing.T) {
 	test.WriteConfig(t, configPath, cfg)
 	_, err = cmd(t, "-c", "--config-file", configPath, "--tree-root", tempDir)
 	as.NoError(err)
-	assertStats(t, as, 31, 31, 22, 0)
+	assertStats(t, as, 32, 32, 23, 0)
 
 	// remove go files from the echo formatter
 	echo.Excludes = []string{"*.py", "*.go"}
@@ -238,7 +239,7 @@ func TestIncludesAndExcludes(t *testing.T) {
 	test.WriteConfig(t, configPath, cfg)
 	_, err = cmd(t, "-c", "--config-file", configPath, "--tree-root", tempDir)
 	as.NoError(err)
-	assertStats(t, as, 31, 31, 21, 0)
+	assertStats(t, as, 32, 32, 22, 0)
 
 	// adjust the includes for echo to only include elm files
 	echo.Includes = []string{"*.elm"}
@@ -246,7 +247,7 @@ func TestIncludesAndExcludes(t *testing.T) {
 	test.WriteConfig(t, configPath, cfg)
 	_, err = cmd(t, "-c", "--config-file", configPath, "--tree-root", tempDir)
 	as.NoError(err)
-	assertStats(t, as, 31, 31, 1, 0)
+	assertStats(t, as, 32, 32, 1, 0)
 
 	// add js files to echo formatter
 	echo.Includes = []string{"*.elm", "*.js"}
@@ -254,7 +255,7 @@ func TestIncludesAndExcludes(t *testing.T) {
 	test.WriteConfig(t, configPath, cfg)
 	_, err = cmd(t, "-c", "--config-file", configPath, "--tree-root", tempDir)
 	as.NoError(err)
-	assertStats(t, as, 31, 31, 2, 0)
+	assertStats(t, as, 32, 32, 2, 0)
 }
 
 func TestCache(t *testing.T) {
@@ -281,7 +282,7 @@ func TestCache(t *testing.T) {
 	test.WriteConfig(t, configPath, cfg)
 	_, err = cmd(t, "--config-file", configPath, "--tree-root", tempDir)
 	as.NoError(err)
-	assertStats(t, as, 31, 31, 31, 0)
+	assertStats(t, as, 32, 32, 32, 0)
 
 	out, err = cmd(t, "--config-file", configPath, "--tree-root", tempDir)
 	as.NoError(err)
@@ -290,7 +291,7 @@ func TestCache(t *testing.T) {
 	// clear cache
 	_, err = cmd(t, "--config-file", configPath, "--tree-root", tempDir, "-c")
 	as.NoError(err)
-	assertStats(t, as, 31, 31, 31, 0)
+	assertStats(t, as, 32, 32, 32, 0)
 
 	out, err = cmd(t, "--config-file", configPath, "--tree-root", tempDir)
 	as.NoError(err)
@@ -299,7 +300,7 @@ func TestCache(t *testing.T) {
 	// clear cache
 	_, err = cmd(t, "--config-file", configPath, "--tree-root", tempDir, "-c")
 	as.NoError(err)
-	assertStats(t, as, 31, 31, 31, 0)
+	assertStats(t, as, 32, 32, 32, 0)
 
 	out, err = cmd(t, "--config-file", configPath, "--tree-root", tempDir)
 	as.NoError(err)
@@ -308,7 +309,7 @@ func TestCache(t *testing.T) {
 	// no cache
 	_, err = cmd(t, "--config-file", configPath, "--tree-root", tempDir, "--no-cache")
 	as.NoError(err)
-	assertStats(t, as, 31, 31, 31, 0)
+	assertStats(t, as, 32, 32, 32, 0)
 }
 
 func TestChangeWorkingDirectory(t *testing.T) {
@@ -342,7 +343,7 @@ func TestChangeWorkingDirectory(t *testing.T) {
 	// this should fail if the working directory hasn't been changed first
 	_, err = cmd(t, "-C", tempDir)
 	as.NoError(err)
-	assertStats(t, as, 31, 31, 31, 0)
+	assertStats(t, as, 32, 32, 32, 0)
 }
 
 func TestFailOnChange(t *testing.T) {
@@ -365,6 +366,9 @@ func TestFailOnChange(t *testing.T) {
 	_, err := cmd(t, "--fail-on-change", "--config-file", configPath, "--tree-root", tempDir)
 	as.ErrorIs(err, ErrFailOnChange)
 
+	// we have second precision mod time tracking
+	time.Sleep(time.Second)
+
 	// test with no cache
 	test.WriteConfig(t, configPath, cfg)
 	_, err = cmd(t, "--fail-on-change", "--config-file", configPath, "--tree-root", tempDir, "--no-cache")
@@ -411,31 +415,31 @@ func TestBustCacheOnFormatterChange(t *testing.T) {
 	args := []string{"--config-file", configPath, "--tree-root", tempDir}
 	_, err := cmd(t, args...)
 	as.NoError(err)
-	assertStats(t, as, 31, 31, 3, 0)
+	assertStats(t, as, 32, 32, 3, 0)
 
 	// tweak mod time of elm formatter
 	as.NoError(test.RecreateSymlink(t, binPath+"/"+"elm-format"))
 
 	_, err = cmd(t, args...)
 	as.NoError(err)
-	assertStats(t, as, 31, 31, 3, 0)
+	assertStats(t, as, 32, 32, 3, 0)
 
 	// check cache is working
 	_, err = cmd(t, args...)
 	as.NoError(err)
-	assertStats(t, as, 31, 0, 0, 0)
+	assertStats(t, as, 32, 0, 0, 0)
 
 	// tweak mod time of python formatter
 	as.NoError(test.RecreateSymlink(t, binPath+"/"+"black"))
 
 	_, err = cmd(t, args...)
 	as.NoError(err)
-	assertStats(t, as, 31, 31, 3, 0)
+	assertStats(t, as, 32, 32, 3, 0)
 
 	// check cache is working
 	_, err = cmd(t, args...)
 	as.NoError(err)
-	assertStats(t, as, 31, 0, 0, 0)
+	assertStats(t, as, 32, 0, 0, 0)
 
 	// add go formatter
 	cfg.Formatters["go"] = &config.Formatter{
@@ -447,12 +451,12 @@ func TestBustCacheOnFormatterChange(t *testing.T) {
 
 	_, err = cmd(t, args...)
 	as.NoError(err)
-	assertStats(t, as, 31, 31, 4, 0)
+	assertStats(t, as, 32, 32, 4, 0)
 
 	// check cache is working
 	_, err = cmd(t, args...)
 	as.NoError(err)
-	assertStats(t, as, 31, 0, 0, 0)
+	assertStats(t, as, 32, 0, 0, 0)
 
 	// remove python formatter
 	delete(cfg.Formatters, "python")
@@ -460,12 +464,12 @@ func TestBustCacheOnFormatterChange(t *testing.T) {
 
 	_, err = cmd(t, args...)
 	as.NoError(err)
-	assertStats(t, as, 31, 31, 2, 0)
+	assertStats(t, as, 32, 32, 2, 0)
 
 	// check cache is working
 	_, err = cmd(t, args...)
 	as.NoError(err)
-	assertStats(t, as, 31, 0, 0, 0)
+	assertStats(t, as, 32, 0, 0, 0)
 
 	// remove elm formatter
 	delete(cfg.Formatters, "elm")
@@ -473,12 +477,12 @@ func TestBustCacheOnFormatterChange(t *testing.T) {
 
 	_, err = cmd(t, args...)
 	as.NoError(err)
-	assertStats(t, as, 31, 31, 1, 0)
+	assertStats(t, as, 32, 32, 1, 0)
 
 	// check cache is working
 	_, err = cmd(t, args...)
 	as.NoError(err)
-	assertStats(t, as, 31, 0, 0, 0)
+	assertStats(t, as, 32, 0, 0, 0)
 }
 
 func TestGitWorktree(t *testing.T) {
@@ -524,7 +528,7 @@ func TestGitWorktree(t *testing.T) {
 	// add everything to the worktree
 	as.NoError(wt.AddGlob("."))
 	as.NoError(err)
-	run(31, 31, 31, 0)
+	run(32, 32, 32, 0)
 
 	// remove python directory
 	as.NoError(wt.RemoveGlob("python/*"))
@@ -533,7 +537,7 @@ func TestGitWorktree(t *testing.T) {
 	// walk with filesystem instead of git
 	_, err = cmd(t, "-c", "--config-file", configPath, "--tree-root", tempDir, "--walk", "filesystem")
 	as.NoError(err)
-	assertStats(t, as, 59, 59, 59, 0)
+	assertStats(t, as, 61, 61, 61, 0)
 }
 
 func TestPathsArg(t *testing.T) {
@@ -568,7 +572,7 @@ func TestPathsArg(t *testing.T) {
 	// without any path args
 	_, err = cmd(t, "-C", tempDir)
 	as.NoError(err)
-	assertStats(t, as, 31, 31, 31, 0)
+	assertStats(t, as, 32, 32, 32, 0)
 
 	// specify some explicit paths
 	_, err = cmd(t, "-C", tempDir, "-c", "elm/elm.json", "haskell/Nested/Foo.hs")
diff --git a/flake.lock b/flake.lock
index c8dc145d..a1394398 100644
--- a/flake.lock
+++ b/flake.lock
@@ -29,11 +29,11 @@
         ]
       },
       "locked": {
-        "lastModified": 1713532798,
-        "narHash": "sha256-wtBhsdMJA3Wa32Wtm1eeo84GejtI43pMrFrmwLXrsEc=",
+        "lastModified": 1717408969,
+        "narHash": "sha256-Q0OEFqe35fZbbRPPRdrjTUUChKVhhWXz3T9ZSKmaoVY=",
         "owner": "numtide",
         "repo": "devshell",
-        "rev": "12e914740a25ea1891ec619bb53cf5e6ca922e40",
+        "rev": "1ebbe68d57457c8cae98145410b164b5477761f4",
         "type": "github"
       },
       "original": {
@@ -44,11 +44,11 @@
     },
     "flake-compat": {
       "locked": {
-        "lastModified": 1688025799,
-        "narHash": "sha256-ktpB4dRtnksm9F5WawoIkEneh1nrEvuxb5lJFt1iOyw=",
+        "lastModified": 1717312683,
+        "narHash": "sha256-FrlieJH50AuvagamEvWMIE6D2OAnERuDboFDYAED/dE=",
         "owner": "nix-community",
         "repo": "flake-compat",
-        "rev": "8bf105319d44f6b9f0d764efa4fdef9f1cc9ba1c",
+        "rev": "38fd3954cf65ce6faf3d0d45cd26059e059f07ea",
         "type": "github"
       },
       "original": {
@@ -86,11 +86,11 @@
         ]
       },
       "locked": {
-        "lastModified": 1710154385,
-        "narHash": "sha256-4c3zQ2YY4BZOufaBJB4v9VBBeN2dH7iVdoJw8SDNCfI=",
+        "lastModified": 1717050755,
+        "narHash": "sha256-C9IEHABulv2zEDFA+Bf0E1nmfN4y6MIUe5eM2RCrDC0=",
         "owner": "nix-community",
         "repo": "gomod2nix",
-        "rev": "872b63ddd28f318489c929d25f1f0a3c6039c971",
+        "rev": "31b6d2e40b36456e792cd6cf50d5a8ddd2fa59a1",
         "type": "github"
       },
       "original": {
@@ -116,11 +116,11 @@
     },
     "nixpkgs": {
       "locked": {
-        "lastModified": 1714253743,
-        "narHash": "sha256-mdTQw2XlariysyScCv2tTE45QSU9v/ezLcHJ22f0Nxc=",
+        "lastModified": 1720031269,
+        "narHash": "sha256-rwz8NJZV+387rnWpTYcXaRNvzUSnnF9aHONoJIYmiUQ=",
         "owner": "nixos",
         "repo": "nixpkgs",
-        "rev": "58a1abdbae3217ca6b702f03d3b35125d88a2994",
+        "rev": "9f4128e00b0ae8ec65918efeba59db998750ead6",
         "type": "github"
       },
       "original": {
@@ -178,11 +178,11 @@
         ]
       },
       "locked": {
-        "lastModified": 1715940852,
-        "narHash": "sha256-wJqHMg/K6X3JGAE9YLM0LsuKrKb4XiBeVaoeMNlReZg=",
+        "lastModified": 1719887753,
+        "narHash": "sha256-p0B2r98UtZzRDM5miGRafL4h7TwGRC4DII+XXHDHqek=",
         "owner": "numtide",
         "repo": "treefmt-nix",
-        "rev": "2fba33a182602b9d49f0b2440513e5ee091d838b",
+        "rev": "bdb6355009562d8f9313d9460c0d3860f525bc6c",
         "type": "github"
       },
       "original": {
diff --git a/nix/packages/treefmt/formatters.nix b/nix/packages/treefmt/formatters.nix
index 8454d9d1..8f42442a 100644
--- a/nix/packages/treefmt/formatters.nix
+++ b/nix/packages/treefmt/formatters.nix
@@ -16,6 +16,8 @@ with pkgs; [
   statix
   deadnix
   terraform
+  dos2unix
+  yamlfmt
   # util for unit testing
   (pkgs.writeShellApplication {
     name = "test-fmt";
diff --git a/test/examples/treefmt.toml b/test/examples/treefmt.toml
index 2291ca82..78640a3b 100644
--- a/test/examples/treefmt.toml
+++ b/test/examples/treefmt.toml
@@ -91,5 +91,14 @@ command = "terraform"
 options = ["fmt"]
 includes = ["*.tf"]
 
+[formatter.dos2unix]
+command = "dos2unix"
+includes = ["*.yaml"]
+options = ["--keepdate"]
+
+[formatter.yamlfmt]
+command = "yamlfmt"
+includes = ["*.yaml"]
+
 [formatter.foo-fmt]
 command = "foo-fmt"
\ No newline at end of file
diff --git a/test/examples/yaml/test.yaml b/test/examples/yaml/test.yaml
new file mode 100644
index 00000000..9df8f9bc
--- /dev/null
+++ b/test/examples/yaml/test.yaml
@@ -0,0 +1,5 @@
+hello: world
+list:
+  - one
+  - two
+  - three
diff --git a/test/temp.go b/test/temp.go
index 36d0df27..2194df2a 100644
--- a/test/temp.go
+++ b/test/temp.go
@@ -4,6 +4,7 @@ import (
 	"io"
 	"os"
 	"testing"
+	"time"
 
 	"git.numtide.com/numtide/treefmt/config"
 
@@ -27,6 +28,11 @@ func WriteConfig(t *testing.T, path string, cfg config.Config) {
 func TempExamples(t *testing.T) string {
 	tempDir := t.TempDir()
 	require.NoError(t, cp.Copy("../test/examples", tempDir), "failed to copy test data to temp dir")
+
+	// we have second precision mod time tracking, so we wait a second before returning, so we don't trigger false
+	//positives for things like fail on change
+	time.Sleep(time.Second)
+
 	return tempDir
 }
 
diff --git a/walk/walker.go b/walk/walker.go
index 6ff10914..e3afb77f 100644
--- a/walk/walker.go
+++ b/walk/walker.go
@@ -4,6 +4,8 @@ import (
 	"context"
 	"fmt"
 	"io/fs"
+	"os"
+	"time"
 )
 
 type Type string
@@ -20,6 +22,29 @@ type File struct {
 	Info    fs.FileInfo
 }
 
+func (f File) HasChanged() (bool, fs.FileInfo, error) {
+	// get the file's current state
+	current, err := os.Stat(f.Path)
+	if err != nil {
+		return false, nil, fmt.Errorf("failed to stat %s: %w", f.Path, err)
+	}
+
+	// check the size first
+	if f.Info.Size() != current.Size() {
+		return true, current, nil
+	}
+
+	// POSIX specifies EPOCH time for Mod time, but some filesystems give more precision.
+	// Some formatters mess with the mod time (e.g., dos2unix) but not to the same precision,
+	// triggering false positives.
+	// We truncate everything below a second.
+	if f.Info.ModTime().Truncate(time.Second) != current.ModTime().Truncate(time.Second) {
+		return true, current, nil
+	}
+
+	return false, nil, nil
+}
+
 func (f File) String() string {
 	return f.Path
 }