diff --git a/Makefile b/Makefile
index 0a98e23..4b45bfb 100644
--- a/Makefile
+++ b/Makefile
@@ -42,12 +42,14 @@ CFLAGS     += -fPIC
 hdrs       += include/bytes.h
 hdrs       += include/haggis.h
 hdrs       += include/jobq.h
+hdrs       += include/mq.h
 
 mans       += man/haggis_node.3
 
 srcs       += bytes.c
 srcs       += haggis.c
 srcs       += jobq.c
+srcs       += mq.c
 srcs       += linkmap.c
 
 objs        = $(srcs:.c=.o)
diff --git a/haggis.c b/haggis.c
index 01a98c8..c10c063 100644
--- a/haggis.c
+++ b/haggis.c
@@ -30,6 +30,7 @@
  *      other than his own.
  */
 
+#include <assert.h>
 #include <errno.h>
 #include <limits.h>          // PATH_MAX
 #include <stdint.h>          // uint<x>_t
@@ -635,8 +636,61 @@ haggis_node* haggis_create_node(char *file, haggis_algorithm a, haggis_linkmap *
     return node;
 }
 
+int haggis_extract_dev(haggis_node *node, char *basedir) {
+    // todo
+    assert(node->filetype.tag == block || node->filetype.tag == character);
+    return 0;
+}
+
+int haggis_extract_fifo(haggis_node *node, char *basedir) {
+    // todo
+    assert(node->filetype.tag == fifo);
+    return 0;
+}
+
+int haggis_extract_symlink(haggis_node *node, char *basedir) {
+    // todo
+    assert(node->filetype.tag == softlink);
+    return 0;
+}
+
+int haggis_extract_hardlink(haggis_node *node, char *basedir) {
+    // todo
+    assert(node->filetype.tag == hardlink);
+    return 0;
+}
+
+int haggis_extract_dir(haggis_node *node, char *basedir) {
+    // todo
+    assert(node->filetype.tag == directory);
+    return 0;
+}
+
+int haggis_extract_file(haggis_node *node, char *basedir) {
+    // todo
+    assert(node->filetype.tag == normal);
+    return 0;
+}
+
 int haggis_extract_node(FILE *stream, char *basedir, haggis_node *node) {
     // todo
+    switch (node->filetype.tag) {
+    case block:
+    case character:
+        return haggis_extract_dev(node, basedir);
+    case fifo:
+        return haggis_extract_fifo(node, basedir);
+    case softlink:
+        return haggis_extract_symlink(node, basedir);
+    case hardlink:
+        return haggis_extract_hardlink(node, basedir);
+    case directory:
+        return haggis_extract_dir(node, basedir);
+    case normal:
+        return haggis_extract_file(node, basedir);
+    case eof:
+        return 0;
+    }
     return 0;
 }
 
diff --git a/include/mq.h b/include/mq.h
new file mode 100644
index 0000000..5b5f8fe
--- /dev/null
+++ b/include/mq.h
@@ -0,0 +1,72 @@
+/*                 _,.---._    .-._        .--.-. ,--.--------.         
+ *   _,..---._   ,-.' , -  `. /==/ \  .-._/==/  //==/,  -   , -\
+ * /==/,   -  \ /==/_,  ,  - \|==|, \/ /, |==\ -\\==\.-.  - ,-./        
+ * |==|   _   _\==|   .=.     |==|-  \|  | \==\- \`--`\==\- \
+ * |==|  .=.   |==|_ : ;=:  - |==| ,  | -|  `--`-'     \==\_ \
+ * |==|,|   | -|==| , '='     |==| -   _ |             |==|- |          
+ * |==|  '='   /\==\ -    ,_ /|==|  /\ , |             |==|, |          
+ * |==|-,   _`/  '.='. -   .' /==/, | |- |             /==/ -/          
+ * `-.`.____.'     `--`--''   `--`./  `--`             `--`--`          
+ *                    _ __    ,---.      .-._         .=-.-.  _,.----.   
+ *                 .-`.' ,`..--.'  \    /==/ \  .-._ /==/_ /.' .' -   \
+ *                /==/, -   \==\-/\ \   |==|, \/ /, /==|, |/==/  ,  ,-'  
+ *               |==| _ .=. /==/-|_\ |  |==|-  \|  ||==|  ||==|-   |  .  
+ *               |==| , '=',\==\,   - \ |==| ,  | -||==|- ||==|_   `-' \
+ *               |==|-  '..'/==/ -   ,| |==| -   _ ||==| ,||==|   _  , | 
+ *               |==|,  |  /==/-  /\ - \|==|  /\ , ||==|- |\==\.       / 
+ *               /==/ - |  \==\ _.\=\.-'/==/, | |- |/==/. / `-.`.___.-'  
+ *               `--`---'   `--`        `--`./  `--``--`-`
+ *
+ *	@(#)Copyright (c) 2023, Nathan D. Fisher.
+ *
+ *      This is free software.  It comes with NO WARRANTY.
+ *      Permission to use, modify and distribute this source code
+ *      is granted subject to the following conditions.
+ *      1/ that the above copyright notice and this notice
+ *      are preserved in all copies and that due credit be given
+ *      to the author.
+ *      2/ that any changes to this code are clearly commented
+ *      as such so that the author does not get blamed for bugs
+ *      other than his own.
+*/
+
+#ifndef MQ_H
+#define MQ_H 1
+
+#include <pthread.h>
+
+#include "haggis.h"
+
+typedef enum {
+    NodeCreated,
+    NodeExtracted,
+    EndOfArchive,
+    ArchiveError,
+} haggis_message_type;
+
+typedef union {
+    char *f_name;
+    int errno;
+} haggis_message_body;
+
+struct _mq_node {
+    struct _mq_node *prev;
+    struct _mq_node *next;
+    haggis_message_type tag;
+    haggis_message_body body;
+};
+
+typedef struct _mq_node haggis_msg;
+
+typedef struct {
+    pthread_cond_t *cond;
+    size_t count;
+    pthread_mutex_t *mutex;
+    haggis_msg *head;
+    haggis_msg *tail;
+} haggis_mq;
+
+int haggis_mq_push(haggis_mq *queue, haggis_msg *msg);
+haggis_msg* haggis_mq_pop(haggis_mq *queue);
+
+#endif // !JOBQ_H
diff --git a/mq.c b/mq.c
new file mode 100644
index 0000000..3664e1c
--- /dev/null
+++ b/mq.c
@@ -0,0 +1,80 @@
+/*                 _,.---._    .-._        .--.-. ,--.--------.         
+ *   _,..---._   ,-.' , -  `. /==/ \  .-._/==/  //==/,  -   , -\
+ * /==/,   -  \ /==/_,  ,  - \|==|, \/ /, |==\ -\\==\.-.  - ,-./        
+ * |==|   _   _\==|   .=.     |==|-  \|  | \==\- \`--`\==\- \
+ * |==|  .=.   |==|_ : ;=:  - |==| ,  | -|  `--`-'     \==\_ \
+ * |==|,|   | -|==| , '='     |==| -   _ |             |==|- |          
+ * |==|  '='   /\==\ -    ,_ /|==|  /\ , |             |==|, |          
+ * |==|-,   _`/  '.='. -   .' /==/, | |- |             /==/ -/          
+ * `-.`.____.'     `--`--''   `--`./  `--`             `--`--`          
+ *                    _ __    ,---.      .-._         .=-.-.  _,.----.   
+ *                 .-`.' ,`..--.'  \    /==/ \  .-._ /==/_ /.' .' -   \
+ *                /==/, -   \==\-/\ \   |==|, \/ /, /==|, |/==/  ,  ,-'  
+ *               |==| _ .=. /==/-|_\ |  |==|-  \|  ||==|  ||==|-   |  .  
+ *               |==| , '=',\==\,   - \ |==| ,  | -||==|- ||==|_   `-' \
+ *               |==|-  '..'/==/ -   ,| |==| -   _ ||==| ,||==|   _  , | 
+ *               |==|,  |  /==/-  /\ - \|==|  /\ , ||==|- |\==\.       / 
+ *               /==/ - |  \==\ _.\=\.-'/==/, | |- |/==/. / `-.`.___.-'  
+ *               `--`---'   `--`        `--`./  `--``--`-`
+ *
+ *	@(#)Copyright (c) 2023, Nathan D. Fisher.
+ *
+ *      This is free software.  It comes with NO WARRANTY.
+ *      Permission to use, modify and distribute this source code
+ *      is granted subject to the following conditions.
+ *      1/ that the above copyright notice and this notice
+ *      are preserved in all copies and that due credit be given
+ *      to the author.
+ *      2/ that any changes to this code are clearly commented
+ *      as such so that the author does not get blamed for bugs
+ *      other than his own.
+*/
+#include <stdlib.h>    // free, malloc
+
+#include "mq.h"
+
+haggis_msg* haggis_msg_init(haggis_message_type tag, haggis_message_body body) {
+    haggis_msg *msg = calloc(1, sizeof(haggis_msg));
+    if (msg == NULL)
+        return NULL;
+    msg->next = msg->prev = NULL;
+    msg->tag = tag;
+    msg->body = body;
+    return msg;
+}
+
+int haggis_mq_push(haggis_mq *queue, haggis_msg *msg) {
+    msg->next = msg->prev = NULL;
+
+    pthread_mutex_lock(queue->mutex);
+    if (queue->tail == NULL) {
+        queue->tail = queue->head = msg;
+    } else {
+        msg->next = queue->tail;
+        queue->tail->prev = msg;
+        queue->tail = msg;
+    }
+    queue->count++;
+    pthread_mutex_unlock(queue->mutex);
+    return 0;
+}
+
+haggis_msg* haggis_mq_pop(haggis_mq *queue) {
+    haggis_msg *msg;
+
+    while (queue->count == 0)
+        pthread_cond_wait(queue->cond, queue->mutex);
+    pthread_mutex_lock(queue->mutex);
+    queue->count--;
+    msg = queue->head;
+    if (msg->tag == EndOfArchive)
+        return NULL;
+    if (queue->tail == queue->head) {
+        queue->tail = queue->head = NULL;
+    } else {
+        queue->head = queue->head->prev;
+    }
+    pthread_mutex_unlock(queue->mutex);
+    msg->prev = msg->next = NULL;
+    return msg;
+}