diff --git a/Makefile b/Makefile
index def6dd9..f89c955 100644
--- a/Makefile
+++ b/Makefile
@@ -5,7 +5,8 @@ types.go \
 config.go \
 spooler.go \
 commits.go \
-workers.go
+workers.go \
+exec.go
 
 all: scorshd
 
@@ -16,7 +17,7 @@ deps:
 	go get 'golang.org/x/crypto/openpgp'
 
 scorshd: $(SERVER_SOURCES)
-	$(BUILD) scorshd.go types.go config.go spooler.go commits.go workers.go
+	$(BUILD) $(SERVER_SOURCES)
 
 clean:
 	rm scorshd
diff --git a/commits.go b/commits.go
index 4f2f451..68c8099 100644
--- a/commits.go
+++ b/commits.go
@@ -94,18 +94,6 @@ func find_tag_config(tag_name string, w *SCORSHworker) (*SCORSHtag_cfg, bool) {
 	return nil, false
 }
 
-func exec_tag(tag *SCORSHtag_cfg) []error {
-
-	var ret []error
-
-	for _, c := range tag.Commands {
-		debug.log("[tag: %s] attempting command: %s\n", tag.Name, c.URL)
-
-		ret = append(ret, nil)
-	}
-	return ret
-}
-
 // traverse all the commits between two references, looking for scorsh
 // commands
 // fixme: we don't have just one keyring here....
@@ -182,6 +170,7 @@ func walk_commits(msg SCORSHmsg, w *SCORSHworker) error {
 					debug.log("[worker: %s] good_tag: %s\n", w.Name, good_tag)
 
 					if !good_tag {
+						debug.log("[worker: %s] unsupported tag: %s\n", w.Name, t.Tag)
 						continue
 					}
 
@@ -190,20 +179,19 @@ func walk_commits(msg SCORSHmsg, w *SCORSHworker) error {
 					debug.log("[worker: %s] good_keys: %s\n", w.Name, good_keys)
 
 					if !good_keys {
+						debug.log("[worker: %s] no matching keys for tag: %s\n", w.Name, t.Tag)
 						continue
 					}
 
 					// c) If everything is OK, execute the tag
 					if good_tag && good_keys {
-						errs := exec_tag(tag_cfg)
+						env := set_environment(&msg)
+						errs := exec_tag(tag_cfg, t.Args, env)
 						debug.log("[worker: %s] errors in tag %s: %s\n", w.Name, t.Tag, errs)
 					}
 				}
 			}
 
-			//signature, signed, err := check_signature(commit, &w.Keys)
-			//_, _, err := check_signature(commit, w.keys)
-
 			cur_commit = commit.Parent(0)
 		} else {
 			fmt.Printf("Commit %x not found!\n", cur_commit.Id())
diff --git a/exec.go b/exec.go
new file mode 100644
index 0000000..e2b22f1
--- /dev/null
+++ b/exec.go
@@ -0,0 +1,71 @@
+package main
+
+import (
+	"fmt"
+	"log"
+	"net/url"
+	"os"
+	"os/exec"
+)
+
+func exec_local_file(cmd_url *url.URL, args, env []string) error {
+
+	cmd := exec.Command(cmd_url.Path, args...)
+	cmd.Env = env
+	stdout, err := cmd.StdoutPipe()
+
+	if err != nil {
+		return nil
+	}
+
+	if err == nil {
+		err = cmd.Start()
+		if err == nil {
+			var output []byte
+			_, err := stdout.Read(output)
+			if err != nil {
+				log.Printf("[%s - stout follows: ]\n%s\n", output)
+				err = cmd.Wait()
+			}
+		}
+	}
+
+	return err
+}
+
+func exec_url(cmd_url *url.URL, args, env []string) error {
+
+	return nil
+}
+
+func exec_tag(tag *SCORSHtag_cfg, args []string, env []string) []error {
+
+	var ret []error
+
+	for _, c := range tag.Commands {
+		debug.log("[tag: %s] attempting command: %s\n", tag.Name, c.URL)
+		cmd_url, err := url.Parse(c.URL)
+		if err != nil {
+			log.Printf("[tag: %s] error parsing URL: %s", tag.Name, err)
+		} else {
+			if cmd_url.Scheme == "file" {
+				err = exec_local_file(cmd_url, args, env)
+			} else if cmd_url.Scheme == "http" || cmd_url.Scheme == "https" {
+				err = exec_url(cmd_url, args, env)
+			}
+		}
+		ret = append(ret, err)
+	}
+	return ret
+}
+
+func set_environment(msg *SCORSHmsg) []string {
+
+	env := os.Environ()
+	env = append(env, fmt.Sprintf("SCORSH_REPO=%s", msg.Repo))
+	env = append(env, fmt.Sprintf("SCORSH_BRANCH=%s", msg.Branch))
+	env = append(env, fmt.Sprintf("SCORSH_OLDREV=%s", msg.Old_rev))
+	env = append(env, fmt.Sprintf("SCORSH_NEWREV_=%s", msg.New_rev))
+	env = append(env, fmt.Sprintf("SCORSH_ID_=%s", msg.Id))
+	return env
+}