diff --git a/c/dsls/filter_dsl_wrapper.c b/c/dsls/filter_dsl_wrapper.c
index a4a4523f5..53d02f076 100644
--- a/c/dsls/filter_dsl_wrapper.c
+++ b/c/dsls/filter_dsl_wrapper.c
@@ -1,4 +1,3 @@
-// xxx rename me
 #include <stdio.h>
 #include <stdlib.h>
 #include "filter_dsl_wrapper.h"
@@ -7,7 +6,6 @@
 #include "../lib/mlrutil.h"
 #include "../containers/mlr_dsl_ast.h"
 
-// xxx temp
 void *filter_dsl_lemon_parser_alloc(void *(*mallocProc)(size_t));
 
 // ----------------------------------------------------------------
diff --git a/c/dsls/put_dsl_wrapper.c b/c/dsls/put_dsl_wrapper.c
index 48241ae45..084f5778a 100644
--- a/c/dsls/put_dsl_wrapper.c
+++ b/c/dsls/put_dsl_wrapper.c
@@ -1,4 +1,3 @@
-// xxx rename me
 #include <stdio.h>
 #include <stdlib.h>
 #include "put_dsl_wrapper.h"
diff --git a/c/input/file_reader_mmap.h b/c/input/file_reader_mmap.h
index 7a5a1c7b5..2370fddea 100644
--- a/c/input/file_reader_mmap.h
+++ b/c/input/file_reader_mmap.h
@@ -1,7 +1,6 @@
 #ifndef FILE_READER_MMAP_H
 #define FILE_READER_MMAP_H
 
-// xxx rename to mmap_file_reader
 typedef struct _file_reader_mmap_state_t {
 	char* sol;
 	char* eof;
diff --git a/c/input/lrec_reader_mmap.h b/c/input/lrec_reader_mmap.h
index 4951a5c02..d9ef1695e 100644
--- a/c/input/lrec_reader_mmap.h
+++ b/c/input/lrec_reader_mmap.h
@@ -1,16 +1,12 @@
 #ifndef LREC_READER_MMAP_H
 #define LREC_READER_MMAP_H
 
-// xxx rename x all to indicate line/file reader vs. lrec reader
-
 #include <stdio.h>
 #include "containers/lrec.h"
 #include "mapping/context.h"
 #include "input/file_reader_mmap.h"
 
-// xxx rename mmap_state to mmap_handle?
 typedef lrec_t* lrec_reader_mmap_process_func_t(file_reader_mmap_state_t* pfh, void* pvstate, context_t* pctx);
-// xxx rename to sof_resetter or some such
 typedef void    lrec_reader_mmap_sof_func_t(void* pvstate);
 
 typedef struct _lrec_reader_mmap_t {
diff --git a/c/input/lrec_reader_mmap_csv.c b/c/input/lrec_reader_mmap_csv.c
index 011990639..567a429a1 100644
--- a/c/input/lrec_reader_mmap_csv.c
+++ b/c/input/lrec_reader_mmap_csv.c
@@ -25,7 +25,7 @@ typedef struct _lrec_reader_mmap_csv_state_t {
 	int  allow_repeat_ifs;
 
 	int  expect_header_line_next;
-	hdr_keeper_t* phdr_keeper; // xxx rename to header_keeper
+	hdr_keeper_t* phdr_keeper;
 	lhmslv_t*     phdr_keepers;
 } lrec_reader_mmap_csv_state_t;
 
diff --git a/c/input/lrec_reader_mmap_xtab.c b/c/input/lrec_reader_mmap_xtab.c
index 6677861e9..f5fcf31aa 100644
--- a/c/input/lrec_reader_mmap_xtab.c
+++ b/c/input/lrec_reader_mmap_xtab.c
@@ -10,7 +10,6 @@ typedef struct _lrec_reader_mmap_xtab_state_t {
 	char ips; // xxx make me real
 	int allow_repeat_ips;
 	int at_eof;
-	// xxx need to remember EOF for subsequent read
 } lrec_reader_mmap_xtab_state_t;
 
 // ----------------------------------------------------------------
@@ -23,7 +22,6 @@ static lrec_t* lrec_reader_mmap_xtab_process(file_reader_mmap_state_t* phandle,
 		return lrec_parse_mmap_xtab(phandle, pstate->irs, pstate->ips, pstate->allow_repeat_ips);
 }
 
-// xxx rename resets to sof_reset or some such
 static void lrec_reader_mmap_xtab_sof(void* pvstate) {
 	lrec_reader_mmap_xtab_state_t* pstate = pvstate;
 	pstate->at_eof = FALSE;
diff --git a/c/input/lrec_reader_stdio.h b/c/input/lrec_reader_stdio.h
index 053880d5f..2db607457 100644
--- a/c/input/lrec_reader_stdio.h
+++ b/c/input/lrec_reader_stdio.h
@@ -6,7 +6,6 @@
 #include "mapping/context.h"
 
 typedef lrec_t* lrec_reader_stdio_process_func_t(FILE* fp, void* pvstate, context_t* pctx);
-// xxx rename to sof_func or some such
 typedef void    lrec_reader_stdio_sof_func_t(void* pvstate);
 typedef void    lrec_reader_stdio_free_func_t(void* pvstate);
 
diff --git a/c/input/lrec_reader_stdio_csv.c b/c/input/lrec_reader_stdio_csv.c
index 88004f0f9..c5de77714 100644
--- a/c/input/lrec_reader_stdio_csv.c
+++ b/c/input/lrec_reader_stdio_csv.c
@@ -24,7 +24,7 @@ typedef struct _lrec_reader_stdio_csv_state_t {
 	int  allow_repeat_ifs;
 
 	int  expect_header_line_next;
-	hdr_keeper_t* phdr_keeper; // xxx rename to header_keeper
+	hdr_keeper_t* phdr_keeper;
 	lhmslv_t*     phdr_keepers;
 } lrec_reader_stdio_csv_state_t;
 
diff --git a/c/mapping/mapper_top.c b/c/mapping/mapper_top.c
index 106e606d1..fd88cf1c1 100644
--- a/c/mapping/mapper_top.c
+++ b/c/mapping/mapper_top.c
@@ -68,7 +68,6 @@ static void mapper_top_ingest(lrec_t* pinrec, mapper_top_state_t* pstate) {
 		char* value_field_sval = pb->value;
 		double value_field_dval = mlr_double_from_string_or_die(value_field_sval);
 
-		// xxx rename: for group and value-field-name
 		top_keeper_t* ptop_keeper_for_group = lhmsv_get(group_to_acc_field, value_field_name);
 		if (ptop_keeper_for_group == NULL) {
 			ptop_keeper_for_group = top_keeper_alloc(pstate->top_count);