diff --git a/patch.Make.go b/patch.Make.go
index a71dff2..5341cb8 100644
--- a/patch.Make.go
+++ b/patch.Make.go
@@ -1,10 +1,12 @@
 package forgepb
 
 import (
+	"errors"
 	"fmt"
 	"os"
 	"path/filepath"
 
+	"go.wit.com/lib/protobuf/gitpb"
 	"go.wit.com/log"
 )
 
@@ -15,6 +17,7 @@ func (f *Forge) MakeDevelPatchSet() (*Patchs, error) {
 		return nil, err
 	}
 	defer os.RemoveAll(dir) // clean up
+	pset.TmpDir = dir
 
 	all := f.Repos.SortByGoPath()
 	for all.Scan() {
@@ -28,19 +31,84 @@ func (f *Forge) MakeDevelPatchSet() (*Patchs, error) {
 		if userb == "" {
 			continue
 		}
-		return f.makePatchSetNew(develb, userb)
+		pset.StartBranchName = develb
+		pset.EndBranchName = userb
+		err := pset.makePatchSetNew(repo)
+		if err != nil {
+			return nil, err
+		}
 	}
 	return pset, nil
 }
 
-func (f *Forge) makePatchSetNew(fromBranch string, toBranch string) (*Patchs, error) {
-	return nil, nil
+func (f *Forge) MakeMasterPatchSet() (*Patchs, error) {
+	pset := new(Patchs)
+	dir, err := os.MkdirTemp("", "forge")
+	if err != nil {
+		return nil, err
+	}
+	defer os.RemoveAll(dir) // clean up
+	pset.TmpDir = dir
+
+	all := f.Repos.SortByGoPath()
+	for all.Scan() {
+		repo := all.Next()
+		startb := repo.GetMasterBranchName()
+		endb := repo.GetUserBranchName()
+
+		if startb == "" {
+			continue
+		}
+		if endb == "" {
+			continue
+		}
+		// log.Info("repo", repo.GoPath, startb, "..", endb)
+		pset.StartBranchName = startb
+		pset.EndBranchName = endb
+		err := pset.makePatchSetNew(repo)
+		if err != nil {
+			return nil, err
+		}
+	}
+	return pset, nil
 }
 
-var pset *Patchs
+func (pset *Patchs) makePatchSetNew(repo *gitpb.Repo) error {
+	startBranch := pset.StartBranchName
+	endBranch := pset.EndBranchName
+	repoDir := filepath.Join(pset.TmpDir, repo.GoPath)
+	err := os.MkdirAll(repoDir, 0755)
+	if err != nil {
+		return err
+	}
+
+	// git format-patch branch1..branch2
+	cmd := []string{"git", "format-patch", "-o", repoDir, startBranch + ".." + endBranch}
+	r := repo.Run(cmd)
+	if r.Error != nil {
+		log.Info("git format-patch", repo.FullPath)
+		log.Info("git format-patch", cmd)
+		log.Info("git format-patch error", r.Error)
+		return r.Error
+	}
+	if r.Exit != 0 {
+		log.Info("git format-patch", repo.FullPath)
+		log.Info("git format-patch", cmd)
+		log.Info("git format-patch exit", r.Exit)
+		return errors.New(fmt.Sprintf("git returned %d", r.Exit))
+	}
+	if len(r.Stdout) == 0 {
+		// git created no files to add
+		return nil
+	}
+
+	return pset.addPatchFiles(repoDir)
+}
+
+// var pset *Patchs
 
 func (f *Forge) MakePatchSet() (*Patchs, error) {
-	pset = new(Patchs)
+	pset := new(Patchs)
 	dir, err := os.MkdirTemp("", "forge")
 	if err != nil {
 		return nil, err
@@ -85,13 +153,13 @@ func (f *Forge) MakePatchSet() (*Patchs, error) {
 			continue
 		}
 
-		addPatchFiles(repoDir)
+		pset.addPatchFiles(repoDir)
 	}
 	return pset, nil
 }
 
 // process each file in pDir/
-func addPatchFiles(pDir string) error {
+func (p *Patchs) addPatchFiles(pDir string) error {
 	// log.Info("ADD PATCH FILES ADDED DIR", pDir)
 	var baderr error
 	filepath.Walk(pDir, func(path string, info os.FileInfo, err error) error {
@@ -115,7 +183,7 @@ func addPatchFiles(pDir string) error {
 		patch := new(Patch)
 		patch.Filename = path
 		patch.Data = data
-		pset.Patchs = append(pset.Patchs, patch)
+		p.Patchs = append(p.Patchs, patch)
 		// log.Info("ADDED PATCH FILE", path)
 		return nil
 	})
diff --git a/patch.proto b/patch.proto
index a35bca6..2e463b5 100644
--- a/patch.proto
+++ b/patch.proto
@@ -17,8 +17,14 @@ message Patchs {			// `autogenpb:marshal`
 	string   uuid	        = 1;    // `autogenpb:uuid:0703df95-6a38-4422-994b-c55d3d6001f9` // todo: add file support
 	string   version        = 2;    // could be used for protobuf schema change violations?
 	repeated Patch Patchs  = 3;
-	string   name           = 4;    // could be used for protobuf schema change violations?
-	string   comment        = 5;    // could be used for protobuf schema change violations?
-	string   gitAuthor      = 6;    // could be used for protobuf schema change violations?
-        google.protobuf.Timestamp ctime       = 7; // the git commit timestamp of the version
+	string   name           = 4;    //
+	string   comment        = 5;    //
+	string   gitAuthorName  = 6;    //
+	string   gitAuthorEmail = 7;    //
+        google.protobuf.Timestamp ctime = 8;    // create time of this patchset
+	string   tmpDir                 = 9;    // temp dir
+	string   startBranchName        = 10;   //
+	string   endBranchName          = 11;   //
+	string   startBranchHash        = 12;   //
+	string   endBranchHash          = 13;   //
 }