diff --git a/bisect.c b/bisect.c
index d71c4e4b44b..94bb53c9bf6 100644
--- a/bisect.c
+++ b/bisect.c
@@ -454,7 +454,7 @@ static int register_ref(const char *refname, const char *referent UNUSED, const
 {
 	struct strbuf good_prefix = STRBUF_INIT;
 	strbuf_addstr(&good_prefix, term_good);
-	strbuf_addstr(&good_prefix, "-");
+	strbuf_addch(&good_prefix, '-');
 
 	if (!strcmp(refname, term_bad)) {
 		free(current_bad_oid);
diff --git a/builtin/am.c b/builtin/am.c
index bfa95147cf4..6cb9fd4f45f 100644
--- a/builtin/am.c
+++ b/builtin/am.c
@@ -341,13 +341,11 @@ static void write_author_script(const struct am_state *state)
 
 	strbuf_addstr(&sb, "GIT_AUTHOR_NAME=");
 	sq_quote_buf(&sb, state->author_name);
-	strbuf_addch(&sb, '\n');
 
-	strbuf_addstr(&sb, "GIT_AUTHOR_EMAIL=");
+	strbuf_addstr(&sb, "\nGIT_AUTHOR_EMAIL=");
 	sq_quote_buf(&sb, state->author_email);
-	strbuf_addch(&sb, '\n');
 
-	strbuf_addstr(&sb, "GIT_AUTHOR_DATE=");
+	strbuf_addstr(&sb, "\nGIT_AUTHOR_DATE=");
 	sq_quote_buf(&sb, state->author_date);
 	strbuf_addch(&sb, '\n');
 
diff --git a/builtin/blame.c b/builtin/blame.c
index 6a7bb3b0724..c1ee2585ee8 100644
--- a/builtin/blame.c
+++ b/builtin/blame.c
@@ -148,11 +148,9 @@ static void get_ac_line(const char *inbuf, const char *what,
 
 	if (split_ident_line(&ident, tmp, len)) {
 	error_out:
-		/* Ugh */
-		tmp = "(unknown)";
-		strbuf_addstr(name, tmp);
-		strbuf_addstr(mail, tmp);
-		strbuf_addstr(tz, tmp);
+		strbuf_addstr(name, "(unknown)");
+		strbuf_addstr(mail, "(unknown)");
+		strbuf_addstr(tz, "(unknown)");
 		*time = 0;
 		return;
 	}
diff --git a/builtin/ls-tree.c b/builtin/ls-tree.c
index 8542b5d53e4..605ddb5a719 100644
--- a/builtin/ls-tree.c
+++ b/builtin/ls-tree.c
@@ -37,7 +37,7 @@ static void expand_objectsize(struct strbuf *line, const struct object_id *oid,
 	} else if (padded) {
 		strbuf_addf(line, "%7s", "-");
 	} else {
-		strbuf_addstr(line, "-");
+		strbuf_addch(line, '-');
 	}
 }
 
diff --git a/diff.c b/diff.c
index 266ddf18e73..61434c6cb45 100644
--- a/diff.c
+++ b/diff.c
@@ -1763,7 +1763,7 @@ static void add_line_count(struct strbuf *out, int count)
 		strbuf_addstr(out, "0,0");
 		break;
 	case 1:
-		strbuf_addstr(out, "1");
+		strbuf_addch(out, '1');
 		break;
 	default:
 		strbuf_addf(out, "1,%d", count);
diff --git a/log-tree.c b/log-tree.c
index 83cc4b1cfb7..d0dc065e4f3 100644
--- a/log-tree.c
+++ b/log-tree.c
@@ -452,7 +452,7 @@ void fmt_output_subject(struct strbuf *filename,
 
 		strbuf_addf(&temp, "v%s", info->reroll_count);
 		format_sanitized_subject(filename, temp.buf, temp.len);
-		strbuf_addstr(filename, "-");
+		strbuf_addch(filename, '-');
 		strbuf_release(&temp);
 	}
 	strbuf_addf(filename, "%04d-%s", nr, subject);
diff --git a/merge-ort.c b/merge-ort.c
index 11029c10be3..8bda8170863 100644
--- a/merge-ort.c
+++ b/merge-ort.c
@@ -827,8 +827,7 @@ static void path_msg(struct merge_options *opt,
 
 	va_start(ap, fmt);
 	if (opt->priv->call_depth) {
-		strbuf_addchars(dest, ' ', 2);
-		strbuf_addstr(dest, "From inner merge:");
+		strbuf_addstr(dest, "  From inner merge:");
 		strbuf_addchars(dest, ' ', opt->priv->call_depth * 2);
 	}
 	strbuf_vaddf(dest, fmt, ap);
diff --git a/path.c b/path.c
index 4dcf3c8d40d..04085c164d0 100644
--- a/path.c
+++ b/path.c
@@ -982,7 +982,7 @@ const char *remove_leading_path(const char *in, const char *prefix)
 
 	strbuf_reset(&buf);
 	if (!in[j])
-		strbuf_addstr(&buf, ".");
+		strbuf_addch(&buf, '.');
 	else
 		strbuf_addstr(&buf, in + j);
 	return buf.buf;
diff --git a/protocol-caps.c b/protocol-caps.c
index 855f279c2f7..a841a457bbd 100644
--- a/protocol-caps.c
+++ b/protocol-caps.c
@@ -65,7 +65,7 @@ static void send_info(struct repository *r, struct packet_writer *writer,
 
 		if (info->size) {
 			if (oid_object_info(r, &oid, &object_size) < 0) {
-				strbuf_addstr(&send_buffer, " ");
+				strbuf_addch(&send_buffer, ' ');
 			} else {
 				strbuf_addf(&send_buffer, " %lu", object_size);
 			}
diff --git a/setup.c b/setup.c
index 39ff48d9dc5..27535f9f9a2 100644
--- a/setup.c
+++ b/setup.c
@@ -1550,7 +1550,7 @@ static enum discovery_result setup_git_directory_gently_1(struct strbuf *dir,
 				return GIT_DIR_DISALLOWED_BARE;
 			if (!ensure_valid_ownership(NULL, NULL, dir->buf, report))
 				return GIT_DIR_INVALID_OWNERSHIP;
-			strbuf_addstr(gitdir, ".");
+			strbuf_addch(gitdir, '.');
 			return GIT_DIR_BARE;
 		}
 
diff --git a/trace2/tr2_tgt_normal.c b/trace2/tr2_tgt_normal.c
index baef48aa698..8a05cf2109a 100644
--- a/trace2/tr2_tgt_normal.c
+++ b/trace2/tr2_tgt_normal.c
@@ -226,7 +226,7 @@ static void fn_child_start_fl(const char *file, int line,
 	if (cmd->dir) {
 		strbuf_addstr(&buf_payload, " cd ");
 		sq_quote_buf_pretty(&buf_payload, cmd->dir);
-		strbuf_addstr(&buf_payload, ";");
+		strbuf_addch(&buf_payload, ';');
 	}
 
 	/*
