diff --git a/.editorconfig b/.editorconfig
index e23a3c7..e9c1e63 100644
--- a/.editorconfig
+++ b/.editorconfig
@@ -5,6 +5,5 @@ root = true
 end_of_line = lf
 insert_final_newline = true
 
-[*.v]
-# vfmt wants it :(
+[*.{v,c,h}]
 indent_style = tab
diff --git a/.gitignore b/.gitignore
index aaec9ef..daeb3d3 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,4 +1,4 @@
-*.c
+vieter.c
 /data/
 
 # Build artifacts
diff --git a/CHANGELOG.md b/CHANGELOG.md
index be5f445..6b1e583 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -13,6 +13,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 * Search in list of targets using API & CLI
 * Allow filtering targets by arch value
 
+### Changed
+
+* Rewrote cron expression logic in C
+
 ## [0.5.0](https://git.rustybever.be/vieter-v/vieter/src/tag/0.5.0)
 
 ### Added
diff --git a/Makefile b/Makefile
index 4bd1edc..3571d30 100644
--- a/Makefile
+++ b/Makefile
@@ -1,6 +1,6 @@
 # =====CONFIG=====
 SRC_DIR := src
-SOURCES != find '$(SRC_DIR)' -iname '*.v'
+SOURCES != find '$(SRC_DIR)' -\( -iname '*.v' -or -iname '*.h' -or -iname '*.c' -\)
 
 V_PATH ?= v
 V := $(V_PATH) -showcc -gc boehm -W -d use_openssl -skip-unused
@@ -81,7 +81,7 @@ fmt:
 
 .PHONY: test
 test:
-	$(V) test $(SRC_DIR)
+	$(V) -g test $(SRC_DIR)
 
 .PHONY: clean
 clean:
diff --git a/src/build/queue.v b/src/build/queue.v
index e74529c..abd4ec6 100644
--- a/src/build/queue.v
+++ b/src/build/queue.v
@@ -1,7 +1,7 @@
 module build
 
 import models { BuildConfig, Target }
-import cron.expression { CronExpression, parse_expression }
+import cron
 import time
 import datatypes { MinHeap }
 import util
@@ -13,7 +13,7 @@ pub mut:
 	// Next timestamp from which point this job is allowed to be executed
 	timestamp time.Time
 	// Required for calculating next timestamp after having pop'ed a job
-	ce CronExpression
+	ce &cron.Expression = unsafe { nil }
 	// Actual build config sent to the agent
 	config BuildConfig
 	// Whether this is a one-time job
@@ -30,7 +30,7 @@ fn (r1 BuildJob) < (r2 BuildJob) bool {
 // for each architecture. Agents receive jobs from this queue.
 pub struct BuildJobQueue {
 	// Schedule to use for targets without explicitely defined cron expression
-	default_schedule CronExpression
+	default_schedule &cron.Expression
 	// Base image to use for targets without defined base image
 	default_base_image string
 mut:
@@ -44,9 +44,9 @@ mut:
 }
 
 // new_job_queue initializes a new job queue
-pub fn new_job_queue(default_schedule CronExpression, default_base_image string) BuildJobQueue {
+pub fn new_job_queue(default_schedule &cron.Expression, default_base_image string) BuildJobQueue {
 	return BuildJobQueue{
-		default_schedule: default_schedule
+		default_schedule: unsafe { default_schedule }
 		default_base_image: default_base_image
 		invalidated: map[int]time.Time{}
 	}
@@ -85,14 +85,14 @@ pub fn (mut q BuildJobQueue) insert(input InsertConfig) ! {
 
 		if !input.now {
 			ce := if input.target.schedule != '' {
-				parse_expression(input.target.schedule) or {
+				cron.parse_expression(input.target.schedule) or {
 					return error("Error while parsing cron expression '$input.target.schedule' (id $input.target.id): $err.msg()")
 				}
 			} else {
 				q.default_schedule
 			}
 
-			job.timestamp = ce.next_from_now()!
+			job.timestamp = ce.next_from_now()
 			job.ce = ce
 		} else {
 			job.timestamp = time.now()
@@ -105,8 +105,8 @@ pub fn (mut q BuildJobQueue) insert(input InsertConfig) ! {
 // reschedule the given job by calculating the next timestamp and re-adding it
 // to its respective queue. This function is called by the pop functions
 // *after* having pop'ed the job.
-fn (mut q BuildJobQueue) reschedule(job BuildJob, arch string) ! {
-	new_timestamp := job.ce.next_from_now()!
+fn (mut q BuildJobQueue) reschedule(job BuildJob, arch string) {
+	new_timestamp := job.ce.next_from_now()
 
 	new_job := BuildJob{
 		...job
@@ -168,10 +168,7 @@ pub fn (mut q BuildJobQueue) pop(arch string) ?BuildJob {
 			job = q.queues[arch].pop()?
 
 			if !job.single {
-				// TODO how do we handle this properly? Is it even possible for a
-				// cron expression to not return a next time if it's already been
-				// used before?
-				q.reschedule(job, arch) or {}
+				q.reschedule(job, arch)
 			}
 
 			return job
@@ -198,8 +195,7 @@ pub fn (mut q BuildJobQueue) pop_n(arch string, n int) []BuildJob {
 				job = q.queues[arch].pop() or { break }
 
 				if !job.single {
-					// TODO idem
-					q.reschedule(job, arch) or {}
+					q.reschedule(job, arch)
 				}
 
 				out << job
diff --git a/src/console/schedule/schedule.v b/src/console/schedule/schedule.v
index 7ce0516..ceabf24 100644
--- a/src/console/schedule/schedule.v
+++ b/src/console/schedule/schedule.v
@@ -1,7 +1,7 @@
 module schedule
 
 import cli
-import cron.expression { parse_expression }
+import cron
 import time
 
 // cmd returns the cli submodule for previewing a cron schedule.
@@ -19,10 +19,10 @@ pub fn cmd() cli.Command {
 			},
 		]
 		execute: fn (cmd cli.Command) ! {
-			ce := parse_expression(cmd.args.join(' '))!
+			ce := cron.parse_expression(cmd.args.join(' '))!
 			count := cmd.flags.get_int('count')!
 
-			for t in ce.next_n(time.now(), count)! {
+			for t in ce.next_n(time.now(), count) {
 				println(t)
 			}
 		}
diff --git a/src/console/targets/targets.v b/src/console/targets/targets.v
index 6152a53..709c196 100644
--- a/src/console/targets/targets.v
+++ b/src/console/targets/targets.v
@@ -2,7 +2,7 @@ module targets
 
 import cli
 import conf as vconf
-import cron.expression { parse_expression }
+import cron
 import client { NewTarget }
 import console
 import models { TargetFilter }
@@ -295,7 +295,7 @@ fn patch(conf Config, id string, params map[string]string) ! {
 	// We check the cron expression first because it's useless to send an
 	// invalid one to the server.
 	if 'schedule' in params && params['schedule'] != '' {
-		parse_expression(params['schedule']) or {
+		cron.parse_expression(params['schedule']) or {
 			return error('Invalid cron expression: $err.msg()')
 		}
 	}
diff --git a/src/cron/c/expression.c b/src/cron/c/expression.c
new file mode 100644
index 0000000..4e1ca3c
--- /dev/null
+++ b/src/cron/c/expression.c
@@ -0,0 +1,115 @@
+#include "expression.h"
+#include <time.h>
+
+const uint8_t month_days[] = {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
+
+cron_expression *ce_init() {
+	return malloc(sizeof(cron_expression));
+}
+
+void ce_free(cron_expression *ce) {
+	free(ce->months);
+	free(ce->days);
+	free(ce->hours);
+	free(ce->minutes);
+	free(ce);
+}
+
+void ce_next(cron_simple_time *out, cron_expression *ce, cron_simple_time *ref) {
+	// For all of these values, the rule is the following: if their value is
+	// the length of their respective array in the CronExpression object, that
+	// means we've looped back around. This means that the "bigger" value has
+	// to be incremented by one. For example, if the minutes have looped
+	// around, that means that the hour has to be incremented as well.
+	uint8_t month_index = 0;
+	uint8_t day_index = 0;
+	uint8_t hour_index = 0;
+	uint8_t minute_index = 0;
+
+	// This chain is the same logic multiple times, namely that if a "bigger"
+	// value loops around, then the smaller value will always reset as well.
+	// For example, if we're going to a new day, the hour & minute will always
+	// be their smallest value again.
+	while (month_index < ce->month_count && ref->month > ce->months[month_index]) {
+		month_index++;
+	}
+
+	if (month_index < ce->month_count && ref->month == ce->months[month_index]) {
+		while (day_index < ce->day_count && ref->day > ce->days[day_index]) {
+			day_index++;
+		}
+
+		if (day_index < ce->day_count && ref->day == ce->days[day_index]) {
+			while (hour_index < ce->hour_count && ref->hour > ce->hours[hour_index]) {
+				hour_index++;
+			}
+
+			if (hour_index < ce->hour_count && ref->hour == ce->hours[hour_index]) {
+				// Minute is the only value where we explicitely make sure we
+				// can't match sref's value exactly. This is to ensure we only
+				// return values in the future.
+				while (minute_index < ce->minute_count && ref->minute >= ce->minutes[minute_index]) {
+					minute_index++;
+				}
+			}
+		}
+	}
+
+	// Here, we increment the "bigger" values by one if the smaller ones loop
+	// around. The order is important, as it allows a sort-of waterfall effect
+	// to occur which updates all values if required.
+	if (minute_index == ce->minute_count && hour_index < ce->hour_count) {
+		hour_index++;
+	}
+
+	if (hour_index == ce->hour_count && day_index < ce->day_count) {
+		day_index++;
+	}
+
+	if (day_index == ce->day_count && month_index < ce->month_count) {
+		month_index++;
+	}
+
+	out->minute = ce->minutes[minute_index % ce->minute_count];
+	out->hour = ce->hours[hour_index % ce->hour_count];
+	out->day = ce->days[day_index % ce->day_count];
+
+	// Sometimes, we end up with a day that does not exist within the selected
+	// month, e.g. day 30 in February. When this occurs, we reset day back to
+	// the smallest value & loop over to the next month that does have this
+	// day.
+	if (out->day > month_days[ce->months[month_index % ce->month_count] - 1]) {
+		out->day = ce->days[0];
+		month_index++;
+
+		while (out->day > month_days[ce->months[month_index % ce->month_count] - 1]) {
+			month_index++;
+		}
+	}
+
+	out->month = ce->months[month_index % ce->month_count];
+
+	if (month_index >= ce->month_count) {
+		out->year = ref->year + 1;
+	} else {
+		out->year = ref->year;
+	}
+}
+
+void ce_next_from_now(cron_simple_time *out, cron_expression *ce) {
+	time_t t = time(NULL);
+	struct tm gm;
+	gmtime_r(&t, &gm);
+
+	cron_simple_time ref = {
+		// tm_year contains years since 1900
+		.year = 1900 + gm.tm_year,
+		// tm_mon goes from 0 to 11
+		.month = gm.tm_mon + 1,
+		.day = gm.tm_mday,
+		.hour = gm.tm_hour,
+		.minute = gm.tm_min
+	};
+
+	ce_next(out, ce, &ref);
+}
diff --git a/src/cron/c/expression.h b/src/cron/c/expression.h
new file mode 100644
index 0000000..c599e4e
--- /dev/null
+++ b/src/cron/c/expression.h
@@ -0,0 +1,46 @@
+#ifndef VIETER_CRON
+#define VIETER_CRON
+
+#include <time.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+
+typedef enum cron_parse_error {
+	cron_parse_ok = 0,
+	cron_parse_invalid_expression = 1,
+	cron_parse_invalid_number = 2,
+	cron_parse_out_of_range = 3,
+	cron_parse_too_many_parts = 4
+} cron_parse_error;
+
+typedef struct cron_expression {
+	uint8_t *minutes;
+	uint8_t *hours;
+	uint8_t *days;
+	uint8_t *months;
+	uint8_t minute_count;
+	uint8_t hour_count;
+	uint8_t day_count;
+	uint8_t month_count;
+} cron_expression;
+
+typedef struct cron_simple_time {
+	int year;
+	int month;
+	int day;
+	int hour;
+	int minute;
+} cron_simple_time;
+
+cron_expression *ce_init();
+
+void cron_ce_free(cron_expression *ce);
+
+void cron_ce_next(cron_simple_time *out, cron_expression *ce, cron_simple_time *ref);
+
+void cron_ce_next_from_now(cron_simple_time *out, cron_expression *ce);
+
+enum cron_parse_error cron_ce_parse_expression(cron_expression *out, char *s);
+
+#endif
diff --git a/src/cron/c/parse.c b/src/cron/c/parse.c
new file mode 100644
index 0000000..7a66200
--- /dev/null
+++ b/src/cron/c/parse.c
@@ -0,0 +1,295 @@
+#include "expression.h"
+
+const uint8_t month_days[] = {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
+
+// Allowed value ranges for the minute, hour, day and month field
+const uint8_t min[4] = {0, 0, 1, 1};
+const uint8_t max[4] = {59, 23, 31, 12};
+
+const uint8_t min_parts = 2;
+const uint8_t max_parts = 4;
+
+// Convert a string into a uint8_t value by parsing it using atoi and checking
+// whether it's contained within the given range
+#define SAFE_ATOI(v,s,min,max) \
+	int _##v = atoi(s); \
+	if ((_##v) == 0 && strcmp((s), "0") != 0) { \
+		return cron_parse_invalid_number; \
+	} \
+	if (((_##v) < (min)) || ((_##v) > (max))) { \
+		return cron_parse_out_of_range; \
+	} \
+	v = (uint8_t) (_##v);
+
+#define MAX(x, y) (((x) > (y)) ? (x) : (y))
+
+/**
+ * Given a range expression, produce a bit field defining what numbers in the
+ * min-max range the expression represents. Bit 0 (starting from the
+ * right) corresponds to min, the bit max - min to max. All trailing bits
+ * after this should be ignored. The given bitfield is modified in-place, so
+ * multiple calls of this function can be performed on the same value to create
+ * the effect of ORing their values.
+ *
+ * A range expression has one of the following forms:
+ *
+ * - *
+ * - a
+ * - a-b
+ * - a/c
+ * - a-b/c
+ */
+cron_parse_error ce_parse_range(uint64_t *out, char *s, uint8_t min, uint8_t max) {
+	size_t slash_index = 0;
+	size_t dash_index = 0;
+	size_t i = 0;
+
+	// We first iterate over the string to determine whether it contains a slash
+	// and/or a dash. We know the dash can only be valid if it appears before
+	// the slash.
+	while (s[i] != '\0' && slash_index == 0) {
+		if (s[i] == '/') {
+			slash_index = i;
+
+			s[i] = '\0';
+		} else if (s[i] == '-') {
+			dash_index = i;
+
+			s[i] = '\0';
+		}
+
+		i++;
+	}
+
+	// Parse the three possible numbers in the pattern
+	uint8_t start = min;
+	uint8_t end = max;
+	uint8_t interval = 1;
+
+	// * simply sets start as min and end as max
+	if (!(s[0] == '*' && strlen(s) == 1)) {
+		SAFE_ATOI(start, s, min, max);
+
+		if (dash_index > 0) {
+			SAFE_ATOI(end, &s[dash_index + 1], min, max);
+		}
+	}
+
+	if (slash_index > 0) {
+		SAFE_ATOI(interval, &s[slash_index + 1], 1, max - min);
+	}
+
+	if (dash_index == 0 && slash_index == 0) {
+		*out |= ((uint64_t) 1) << (start - min);
+	} else {
+		while (start <= end) {
+			*out |= ((uint64_t) 1) << (start - min);
+			start += interval;
+		}
+	}
+
+	return cron_parse_ok;
+}
+
+/*
+ * Given an expression part, produce a bitfield defining what numbers in the
+ * min-max range the part represents. A part consists of one or more range
+ * expressions, separated by commas.
+ */
+cron_parse_error ce_parse_part(uint64_t *out, char *s, uint8_t min, uint8_t max) {
+	*out = 0;
+
+	char *next;
+	enum cron_parse_error res;
+
+	while ((next = strchr(s, ',')) != NULL) {
+		next[0] = '\0';
+		res = ce_parse_range(out, s, min, max);
+
+		if (res != cron_parse_ok) {
+			return res;
+		}
+
+		s = next + 1;
+	}
+
+	// Make sure to parse the final range as well
+	return ce_parse_range(out, s, min, max);
+}
+
+/*
+ * Return how many bits are set in the bitfield, better known as popcount. I
+ * added my own implementation (taken from my algorithms course) as I don't want
+ * to be dependent on GCC-specific extensions.
+ */
+uint8_t uint64_t_popcount(uint64_t n) {
+	uint8_t c = 0;
+
+	while (n != 0) {
+		// This sets the least significant bit to zero (very cool)
+		n &= n - 1;
+		c++;
+	}
+
+	return c;
+}
+
+/*
+ * Convert a bitfield into an array containing the numbers in the min-max range
+ * it represents.
+ */
+uint8_t bf_to_nums(uint8_t **out, uint64_t bf, uint8_t min, uint8_t max) {
+	// Each bit field only has `max - min + 1` meaningful bits. All other bits
+	// should be ignored, and can be any value. By shifting the bit field back and
+	// forth, we set these excessive bits to zero, ensuring popcount returns the
+	// correct value.
+	uint8_t excess_bits = 64 - (max - min + 1);
+	bf = (bf << excess_bits) >> excess_bits;
+	uint8_t size = uint64_t_popcount(bf);
+	uint8_t *buf = malloc(size * sizeof(uint8_t));
+
+	uint8_t i = 0, j = 0;
+
+	while (j < size && i <= max - min) {
+		if (((uint64_t)1 << i) & bf) {
+			// Resize buffer if needed
+			buf[j] = min + i;
+			j++;
+		}
+
+		i++;
+	}
+
+	*out = buf;
+
+	return size;
+}
+
+/*
+ * Parse a cron expression string into a cron_expression struct.
+ */
+enum cron_parse_error ce_parse_expression(cron_expression *out, char *s) {
+	// The parsing functions modify the input string in-place
+	s = strdup(s);
+	char *orig_s = s;
+
+	enum cron_parse_error res = cron_parse_ok;
+	uint64_t bfs[max_parts];
+
+	// First we divide the input string into its parts, divided by spaces.
+	// Each part is delimited by a NULL byte.
+	uint8_t part_count = 0;
+	char *parts[max_parts];
+	char *next;
+
+	// Skip leading spaces
+	size_t offset = 0;
+
+	while (s[offset] == ' ') {
+		offset++;
+	}
+
+	s += offset;
+
+	while (part_count < max_parts && ((next = strchr(s, ' ')) != NULL)) {
+		next[0] = '\0';
+		parts[part_count] = s;
+
+		// Skip multiple spaces
+		offset = 1;
+		while (next[offset] == ' ') {
+			offset++;
+		}
+		s = next + offset;
+
+		part_count++;
+	}
+
+	// The loop exited because we already have 4 parts, yet there's still at
+	// least one more part that follows.
+	if (next != NULL) {
+		res = cron_parse_too_many_parts;
+	} else if (s[0] != '\0') {
+		// There's one more excessive trailing part
+		if (part_count == max_parts) {
+			res = cron_parse_too_many_parts;
+			goto end;
+		}
+
+		parts[part_count] = s;
+		part_count++;
+	}
+
+
+	// We now parse the parts in reverse. This is because the month part
+	// determines the maximum value of the day part.
+	
+	uint64_t bit_field = 0;
+	
+	// Months
+	if (part_count >= 4) {
+		res = ce_parse_part(&bit_field, parts[3], min[3], max[3]);
+
+		if (res != cron_parse_ok) {
+			goto end;
+		}
+
+		out->month_count = bf_to_nums(&out->months, bit_field, min[3], max[3]);
+	}
+	// If months aren't provided, they're replaced with a *
+	else {
+		out->month_count = bf_to_nums(&out->months, ~0, min[3], max[3]);
+	}
+
+	// Determine what the largest allowed day value is, given the months
+	uint8_t max_day_value = 0;
+
+	for (uint8_t i = 0; i < out->month_count; i++) {
+		max_day_value = MAX(max_day_value, month_days[out->months[i] - 1]);
+	}
+	
+	// Days
+	if (part_count >= 3) {
+		bit_field = 0;
+
+		res = ce_parse_part(&bit_field, parts[2], min[2], max_day_value);
+
+		if (res != cron_parse_ok) {
+			goto end;
+		}
+
+		out->day_count = bf_to_nums(&out->days, bit_field, min[2], max_day_value);
+	}
+	// If days aren't provided, they're replaced with a *
+	else {
+		out->day_count = bf_to_nums(&out->days, ~0, min[2], max_day_value);
+	}
+
+	// Hours
+	bit_field = 0;
+
+	res = ce_parse_part(&bit_field, parts[1], min[1], max[1]);
+
+	if (res != cron_parse_ok) {
+		goto end;
+	}
+
+	out->hour_count = bf_to_nums(&out->hours, bit_field, min[1], max[1]);
+
+	// Minutes
+	bit_field = 0;
+
+	res = ce_parse_part(&bit_field, parts[0], min[0], max[0]);
+
+	if (res != cron_parse_ok) {
+		goto end;
+	}
+
+	out->minute_count = bf_to_nums(&out->minutes, bit_field, min[0], max[0]);
+
+end:
+	// s is cloned
+	free(orig_s);
+
+	return res;
+}
diff --git a/src/cron/cli.v b/src/cron/cli.v
deleted file mode 100644
index 16a3537..0000000
--- a/src/cron/cli.v
+++ /dev/null
@@ -1,32 +0,0 @@
-module cron
-
-import cli
-import conf as vconf
-
-struct Config {
-pub:
-	log_level               string = 'WARN'
-	api_key                 string
-	address                 string
-	data_dir                string
-	base_image              string = 'archlinux:base-devel'
-	max_concurrent_builds   int    = 1
-	api_update_frequency    int    = 15
-	image_rebuild_frequency int    = 1440
-	// Replicates the behavior of the original cron system
-	global_schedule string = '0 3'
-}
-
-// cmd returns the cli module that handles the cron daemon.
-pub fn cmd() cli.Command {
-	return cli.Command{
-		name: 'cron'
-		description: 'Start the cron service that periodically runs builds.'
-		execute: fn (cmd cli.Command) ! {
-			config_file := cmd.flags.get_string('config-file')!
-			conf := vconf.load<Config>(prefix: 'VIETER_', default_path: config_file)!
-
-			cron(conf)!
-		}
-	}
-}
diff --git a/src/cron/cron.v b/src/cron/cron.v
deleted file mode 100644
index f1d6b7b..0000000
--- a/src/cron/cron.v
+++ /dev/null
@@ -1,33 +0,0 @@
-module cron
-
-import log
-import cron.daemon
-import cron.expression
-import os
-
-const log_file_name = 'vieter.cron.log'
-
-// cron starts a cron daemon & starts periodically scheduling builds.
-pub fn cron(conf Config) ! {
-	// Configure logger
-	log_level := log.level_from_tag(conf.log_level) or {
-		return error('Invalid log level. The allowed values are FATAL, ERROR, WARN, INFO & DEBUG.')
-	}
-
-	mut logger := log.Log{
-		level: log_level
-	}
-
-	log_file := os.join_path_single(conf.data_dir, cron.log_file_name)
-	logger.set_full_logpath(log_file)
-	logger.log_to_console_too()
-
-	ce := expression.parse_expression(conf.global_schedule) or {
-		return error('Error while parsing global cron expression: $err.msg()')
-	}
-
-	mut d := daemon.init_daemon(logger, conf.address, conf.api_key, conf.base_image, ce,
-		conf.max_concurrent_builds, conf.api_update_frequency, conf.image_rebuild_frequency)!
-
-	d.run()
-}
diff --git a/src/cron/daemon/build.v b/src/cron/daemon/build.v
deleted file mode 100644
index 42edc92..0000000
--- a/src/cron/daemon/build.v
+++ /dev/null
@@ -1,115 +0,0 @@
-module daemon
-
-import time
-import sync.stdatomic
-import build
-import os
-
-const (
-	build_empty   = 0
-	build_running = 1
-	build_done    = 2
-)
-
-// clean_finished_builds removes finished builds from the build slots & returns
-// them.
-fn (mut d Daemon) clean_finished_builds() []ScheduledBuild {
-	mut out := []ScheduledBuild{}
-
-	for i in 0 .. d.atomics.len {
-		if stdatomic.load_u64(&d.atomics[i]) == daemon.build_done {
-			stdatomic.store_u64(&d.atomics[i], daemon.build_empty)
-			out << d.builds[i]
-		}
-	}
-
-	return out
-}
-
-// update_builds starts as many builds as possible.
-fn (mut d Daemon) start_new_builds() {
-	now := time.now()
-
-	for d.queue.len() > 0 {
-		elem := d.queue.peek() or {
-			d.lerror("queue.peek() unexpectedly returned an error. This shouldn't happen.")
-
-			break
-		}
-
-		if elem.timestamp < now {
-			sb := d.queue.pop() or {
-				d.lerror("queue.pop() unexpectedly returned an error. This shouldn't happen.")
-
-				break
-			}
-
-			// If this build couldn't be scheduled, no more will be possible.
-			if !d.start_build(sb) {
-				d.queue.insert(sb)
-				break
-			}
-		} else {
-			break
-		}
-	}
-}
-
-// start_build starts a build for the given ScheduledBuild object.
-fn (mut d Daemon) start_build(sb ScheduledBuild) bool {
-	for i in 0 .. d.atomics.len {
-		if stdatomic.load_u64(&d.atomics[i]) == daemon.build_empty {
-			stdatomic.store_u64(&d.atomics[i], daemon.build_running)
-			d.builds[i] = sb
-
-			go d.run_build(i, sb)
-
-			return true
-		}
-	}
-
-	return false
-}
-
-// run_build actually starts the build process for a given target.
-fn (mut d Daemon) run_build(build_index int, sb ScheduledBuild) {
-	d.linfo('started build: $sb.target.url -> $sb.target.repo')
-
-	// 0 means success, 1 means failure
-	mut status := 0
-
-	res := build.build_target(d.client.address, d.client.api_key, d.builder_images.last(),
-		&sb.target, false) or {
-		d.ldebug('build_target error: $err.msg()')
-		status = 1
-
-		build.BuildResult{}
-	}
-
-	if status == 0 {
-		d.linfo('finished build: $sb.target.url -> $sb.target.repo; uploading logs...')
-
-		build_arch := os.uname().machine
-		d.client.add_build_log(sb.target.id, res.start_time, res.end_time, build_arch,
-			res.exit_code, res.logs) or {
-			d.lerror('Failed to upload logs for build: $sb.target.url -> $sb.target.repo')
-		}
-	} else {
-		d.linfo('an error occured during build: $sb.target.url -> $sb.target.repo')
-	}
-
-	stdatomic.store_u64(&d.atomics[build_index], daemon.build_done)
-}
-
-// current_build_count returns how many builds are currently running.
-fn (mut d Daemon) current_build_count() int {
-	mut res := 0
-
-	for i in 0 .. d.atomics.len {
-		if stdatomic.load_u64(&d.atomics[i]) == daemon.build_running {
-			res += 1
-		}
-	}
-
-	return res
-}
diff --git a/src/cron/daemon/daemon.v b/src/cron/daemon/daemon.v
deleted file mode 100644
index b94dab8..0000000
--- a/src/cron/daemon/daemon.v
+++ /dev/null
@@ -1,274 +0,0 @@
-module daemon
-
-import time
-import log
-import datatypes { MinHeap }
-import cron.expression { CronExpression, parse_expression }
-import math
-import build
-import docker
-import os
-import client
-import models { Target }
-
-const (
-	// How many seconds to wait before retrying to update API if failed
-	api_update_retry_timeout        = 5
-	// How many seconds to wait before retrying to rebuild image if failed
-	rebuild_base_image_retry_timout = 30
-)
-
-struct ScheduledBuild {
-pub:
-	target    Target
-	timestamp time.Time
-}
-
-// Overloaded operator for comparing ScheduledBuild objects
-fn (r1 ScheduledBuild) < (r2 ScheduledBuild) bool {
-	return r1.timestamp < r2.timestamp
-}
-
-pub struct Daemon {
-mut:
-	client                  client.Client
-	base_image              string
-	builder_images          []string
-	global_schedule         CronExpression
-	api_update_frequency    int
-	image_rebuild_frequency int
-	// Targets currently loaded from API.
-	targets []Target
-	// At what point to update the list of targets.
-	api_update_timestamp  time.Time
-	image_build_timestamp time.Time
-	queue                 MinHeap<ScheduledBuild>
-	// Which builds are currently running
-	builds []ScheduledBuild
-	// Atomic variables used to detect when a build has finished; length is the
-	// same as builds
-	atomics []u64
-	logger  shared log.Log
-}
-
-// init_daemon initializes a new Daemon object. It renews the targets &
-// populates the build queue for the first time.
-pub fn init_daemon(logger log.Log, address string, api_key string, base_image string, global_schedule CronExpression, max_concurrent_builds int, api_update_frequency int, image_rebuild_frequency int) !Daemon {
-	mut d := Daemon{
-		client: client.new(address, api_key)
-		base_image: base_image
-		global_schedule: global_schedule
-		api_update_frequency: api_update_frequency
-		image_rebuild_frequency: image_rebuild_frequency
-		atomics: []u64{len: max_concurrent_builds}
-		builds: []ScheduledBuild{len: max_concurrent_builds}
-		logger: logger
-	}
-
-	// Initialize the targets & queue
-	d.renew_targets()
-	d.renew_queue()
-	if !d.rebuild_base_image() {
-		return error('The base image failed to build. The Vieter cron daemon cannot run without an initial builder image.')
-	}
-
-	return d
-}
-
-// run starts the actual daemon process. It runs builds when possible &
-// periodically refreshes the list of targets to ensure we stay in sync.
-pub fn (mut d Daemon) run() {
-	for {
-		finished_builds := d.clean_finished_builds()
-
-		// Update the API's contents if needed & renew the queue
-		if time.now() >= d.api_update_timestamp {
-			d.renew_targets()
-			d.renew_queue()
-		}
-		// The finished builds should only be rescheduled if the API contents
-		// haven't been renewed.
-		else {
-			for sb in finished_builds {
-				d.schedule_build(sb.target)
-			}
-		}
-
-		// TODO remove old builder images.
-		// This issue is less trivial than it sounds, because a build could
-		// still be running when the image has to be rebuilt. That would
-		// prevent the image from being removed. Therefore, we will need to
-		// keep track of a list or something & remove an image once we have
-		// made sure it isn't being used anymore.
-		if time.now() >= d.image_build_timestamp {
-			d.rebuild_base_image()
-			// In theory, executing this function here allows an old builder
-			// image to exist for at most image_rebuild_frequency minutes.
-			d.clean_old_base_images()
-		}
-
-		// Schedules new builds when possible
-		d.start_new_builds()
-
-		// If there are builds currently running, the daemon should refresh
-		// every second to clean up any finished builds & start new ones.
-		mut delay := time.Duration(1 * time.second)
-
-		// Sleep either until we have to refresh the targets or when the next
-		// build has to start, with a minimum of 1 second.
-		if d.current_build_count() == 0 {
-			now := time.now()
-			delay = d.api_update_timestamp - now
-
-			if d.queue.len() > 0 {
-				elem := d.queue.peek() or {
-					d.lerror("queue.peek() unexpectedly returned an error. This shouldn't happen.")
-
-					// This is just a fallback option. In theory, queue.peek()
-					// should *never* return an error or none, because we check
-					// its len beforehand.
-					time.sleep(1)
-					continue
-				}
-
-				time_until_next_job := elem.timestamp - now
-
-				delay = math.min(delay, time_until_next_job)
-			}
-		}
-
-		// We sleep for at least one second. This is to prevent the program
-		// from looping agressively when a cronjob can be scheduled, but
-		// there's no spots free for it to be started.
-		delay = math.max(delay, 1 * time.second)
-
-		d.ldebug('Sleeping for ${delay}...')
-
-		time.sleep(delay)
-	}
-}
-
-// schedule_build adds the next occurence of the given targets build to the
-// queue.
-fn (mut d Daemon) schedule_build(target Target) {
-	ce := if target.schedule != '' {
-		parse_expression(target.schedule) or {
-			// TODO This shouldn't return an error if the expression is empty.
-			d.lerror("Error while parsing cron expression '$target.schedule' (id $target.id): $err.msg()")
-
-			d.global_schedule
-		}
-	} else {
-		d.global_schedule
-	}
-
-	// A target that can't be scheduled will just be skipped for now
-	timestamp := ce.next_from_now() or {
-		d.lerror("Couldn't calculate next timestamp from '$target.schedule'; skipping")
-		return
-	}
-
-	d.queue.insert(ScheduledBuild{
-		target: target
-		timestamp: timestamp
-	})
-}
-
-// renew_targets requests the newest list of targets from the server & replaces
-// the old one.
-fn (mut d Daemon) renew_targets() {
-	d.linfo('Renewing targets...')
-
-	mut new_targets := d.client.get_all_targets() or {
-		d.lerror('Failed to renew targets. Retrying in ${daemon.api_update_retry_timeout}s...')
-		d.api_update_timestamp = time.now().add_seconds(daemon.api_update_retry_timeout)
-
-		return
-	}
-
-	// Filter out any targets that shouldn't run on this architecture
-	cur_arch := os.uname().machine
-	new_targets = new_targets.filter(it.arch.any(it.value == cur_arch))
-
-	d.targets = new_targets
-
-	d.api_update_timestamp = time.now().add_seconds(60 * d.api_update_frequency)
-}
-
-// renew_queue replaces the old queue with a new one that reflects the newest
-// values in targets.
-fn (mut d Daemon) renew_queue() {
-	d.linfo('Renewing queue...')
-	mut new_queue := MinHeap<ScheduledBuild>{}
-
-	// Move any jobs that should have already started from the old queue onto
-	// the new one
-	now := time.now()
-
-	// For some reason, using
-	// ```v
-	// for d.queue.len() > 0 && d.queue.peek() !.timestamp < now {
-	//```
-	// here causes the function to prematurely just exit, without any errors or anything, very weird
-	// https://github.com/vlang/v/issues/14042
-	for d.queue.len() > 0 {
-		elem := d.queue.pop() or {
-			d.lerror("queue.pop() returned an error. This shouldn't happen.")
-			continue
-		}
-
-		if elem.timestamp < now {
-			new_queue.insert(elem)
-		} else {
-			break
-		}
-	}
-
-	d.queue = new_queue
-
-	// For each target in targets, parse their cron expression (or use the
-	// default one if not present) & add them to the queue
-	for target in d.targets {
-		d.schedule_build(target)
-	}
-}
-
-// rebuild_base_image recreates the builder image.
-fn (mut d Daemon) rebuild_base_image() bool {
-	d.linfo('Rebuilding builder image....')
-
-	d.builder_images << build.create_build_image(d.base_image) or {
-		d.lerror('Failed to rebuild base image. Retrying in ${daemon.rebuild_base_image_retry_timout}s...')
-		d.image_build_timestamp = time.now().add_seconds(daemon.rebuild_base_image_retry_timout)
-
-		return false
-	}
-
-	d.image_build_timestamp = time.now().add_seconds(60 * d.image_rebuild_frequency)
-
-	return true
-}
-
-// clean_old_base_images tries to remove any old but still present builder
-// images.
-fn (mut d Daemon) clean_old_base_images() {
-	mut i := 0
-
-	mut dd := docker.new_conn() or {
-		d.lerror('Failed to connect to Docker socket.')
-		return
-	}
-
-	defer {
-		dd.close() or {}
-	}
-
-	for i < d.builder_images.len - 1 {
-		// For each builder image, we try to remove it by calling the Docker
-		// API. If the function returns an error or false, that means the image
-		// wasn't deleted. Therefore, we move the index over. If the function
-		// returns true, the array's length has decreased by one so we don't
-		// move the index.
-		dd.image_remove(d.builder_images[i]) or { i += 1 }
-	}
-}
diff --git a/src/cron/daemon/log.v b/src/cron/daemon/log.v
deleted file mode 100644
index 95a50e7..0000000
--- a/src/cron/daemon/log.v
+++ /dev/null
@@ -1,35 +0,0 @@
-module daemon
-
-import log
-
-// log reate a log message with the given level
-pub fn (mut d Daemon) log(msg string, level log.Level) {
-	lock d.logger {
-		d.logger.send_output(msg, level)
-	}
-}
-
-// lfatal create a log message with the fatal level
-pub fn (mut d Daemon) lfatal(msg string) {
-	d.log(msg, log.Level.fatal)
-}
-
-// lerror create a log message with the error level
-pub fn (mut d Daemon) lerror(msg string) {
-	d.log(msg, log.Level.error)
-}
-
-// lwarn create a log message with the warn level
-pub fn (mut d Daemon) lwarn(msg string) {
-	d.log(msg, log.Level.warn)
-}
-
-// linfo create a log message with the info level
-pub fn (mut d Daemon) linfo(msg string) {
-	d.log(msg, log.Level.info)
-}
-
-// ldebug create a log message with the debug level
-pub fn (mut d Daemon) ldebug(msg string) {
-	d.log(msg, log.Level.debug)
-}
diff --git a/src/cron/expression.c.v b/src/cron/expression.c.v
new file mode 100644
index 0000000..cd4b8b0
--- /dev/null
+++ b/src/cron/expression.c.v
@@ -0,0 +1,58 @@
+module cron
+
+#flag -I @VMODROOT/c
+#flag @VMODROOT/c/parse.o
+#flag @VMODROOT/c/expression.o
+#include "expression.h"
+
+pub struct C.cron_expression {
+	minutes      &u8
+	hours        &u8
+	days         &u8
+	months       &u8
+	minute_count u8
+	hour_count   u8
+	day_count    u8
+	month_count  u8
+}
+
+pub type Expression = C.cron_expression
+
+struct C.cron_simple_time {
+	year   int
+	month  int
+	day    int
+	hour   int
+	minute int
+}
+
+type SimpleTime = C.cron_simple_time
+
+enum ParseError as u8 {
+	ok = 0
+	invalid_expression = 1
+	invalid_number = 2
+	out_of_range = 3
+	too_many_parts = 4
+}
+
+// str returns the string representation of a ParseError.
+fn (e ParseError) str() string {
+	return match e {
+		.ok { '' }
+		.invalid_expression { 'Invalid expression' }
+		.invalid_number { 'Invalid number' }
+		.out_of_range { 'Out of range' }
+		.too_many_parts { 'Too many parts' }
+	}
+}
+
+fn C.ce_init() &C.cron_expression
+
+fn C.ce_free(ce &C.cron_expression)
+
+fn C.ce_next(out &C.cron_simple_time, ce &C.cron_expression, ref &C.cron_simple_time)
+
+fn C.ce_next_from_now(out &C.cron_simple_time, ce &C.cron_expression)
+
+fn C.ce_parse_expression(out &C.cron_expression, s &char) ParseError
diff --git a/src/cron/expression.v b/src/cron/expression.v
new file mode 100644
index 0000000..c463d06
--- /dev/null
+++ b/src/cron/expression.v
@@ -0,0 +1,73 @@
+module cron
+
+import time
+
+// free the memory associated with the Expression.
+[unsafe]
+pub fn (ce &Expression) free() {
+	C.ce_free(ce)
+}
+
+// parse_expression parses a string into an Expression.
+pub fn parse_expression(exp string) !&Expression {
+	out := C.ce_init()
+	res := C.ce_parse_expression(out, exp.str)
+
+	if res != .ok {
+		return error(res.str())
+	}
+
+	return out
+}
+
+// next calculates the next occurence of the cron schedule, given a reference
+// point.
+pub fn (ce &Expression) next(ref time.Time) time.Time {
+	st := SimpleTime{
+		year: ref.year
+		month: ref.month
+		day: ref.day
+		hour: ref.hour
+		minute: ref.minute
+	}
+
+	out := SimpleTime{}
+	C.ce_next(&out, ce, &st)
+
+	return time.new_time(time.Time{
+		year: out.year
+		month: out.month
+		day: out.day
+		hour: out.hour
+		minute: out.minute
+	})
+}
+
+// next_from_now calculates the next occurence of the cron schedule with the
+// current time as reference.
+pub fn (ce &Expression) next_from_now() time.Time {
+	out := SimpleTime{}
+	C.ce_next_from_now(&out, ce)
+
+	return time.new_time(time.Time{
+		year: out.year
+		month: out.month
+		day: out.day
+		hour: out.hour
+		minute: out.minute
+	})
+}
+
+// next_n returns the n next occurences of the expression, given a starting
+// time.
+pub fn (ce &Expression) next_n(ref time.Time, n int) []time.Time {
+	mut times := []time.Time{cap: n}
+
+	times << ce.next(ref)
+
+	for i in 1 .. n {
+		times << ce.next(times[i - 1])
+	}
+
+	return times
+}
diff --git a/src/cron/expression/expression.v b/src/cron/expression/expression.v
deleted file mode 100644
index c3ff8c5..0000000
--- a/src/cron/expression/expression.v
+++ /dev/null
@@ -1,136 +0,0 @@
-module expression
-
-import time
-
-pub struct CronExpression {
-	minutes []int
-	hours   []int
-	days    []int
-	months  []int
-}
-
-// next calculates the earliest time this cron expression is valid. It will
-// always pick a moment in the future, even if ref matches completely up to the
-// minute. This function conciously does not take gap years into account.
-pub fn (ce &CronExpression) next(ref time.Time) !time.Time {
-	// If the given ref matches the next cron occurence up to the minute, it
-	// will return that value. Because we always want to return a value in the
-	// future, we artifically shift the ref 60 seconds to make sure we always
-	// match in the future. A shift of 60 seconds is enough because the cron
-	// expression does not allow for accuracy smaller than one minute.
-	sref := ref
-
-	// For all of these values, the rule is the following: if their value is
-	// the length of their respective array in the CronExpression object, that
-	// means we've looped back around. This means that the "bigger" value has
-	// to be incremented by one. For example, if the minutes have looped
-	// around, that means that the hour has to be incremented as well.
-	mut minute_index := 0
-	mut hour_index := 0
-	mut day_index := 0
-	mut month_index := 0
-
-	// This chain is the same logic multiple times, namely that if a "bigger"
-	// value loops around, then the smaller value will always reset as well.
-	// For example, if we're going to a new day, the hour & minute will always
-	// be their smallest value again.
-	for month_index < ce.months.len && sref.month > ce.months[month_index] {
-		month_index++
-	}
-
-	if month_index < ce.months.len && sref.month == ce.months[month_index] {
-		for day_index < ce.days.len && sref.day > ce.days[day_index] {
-			day_index++
-		}
-
-		if day_index < ce.days.len && ce.days[day_index] == sref.day {
-			for hour_index < ce.hours.len && sref.hour > ce.hours[hour_index] {
-				hour_index++
-			}
-
-			if hour_index < ce.hours.len && ce.hours[hour_index] == sref.hour {
-				// Minute is the only value where we explicitely make sure we
-				// can't match sref's value exactly. This is to ensure we only
-				// return values in the future.
-				for minute_index < ce.minutes.len && sref.minute >= ce.minutes[minute_index] {
-					minute_index++
-				}
-			}
-		}
-	}
-
-	// Here, we increment the "bigger" values by one if the smaller ones loop
-	// around. The order is important, as it allows a sort-of waterfall effect
-	// to occur which updates all values if required.
-	if minute_index == ce.minutes.len && hour_index < ce.hours.len {
-		hour_index += 1
-	}
-
-	if hour_index == ce.hours.len && day_index < ce.days.len {
-		day_index += 1
-	}
-
-	if day_index == ce.days.len && month_index < ce.months.len {
-		month_index += 1
-	}
-
-	mut minute := ce.minutes[minute_index % ce.minutes.len]
-	mut hour := ce.hours[hour_index % ce.hours.len]
-	mut day := ce.days[day_index % ce.days.len]
-
-	// Sometimes, we end up with a day that does not exist within the selected
-	// month, e.g. day 30 in February. When this occurs, we reset day back to
-	// the smallest value & loop over to the next month that does have this
-	// day.
-	if day > time.month_days[ce.months[month_index % ce.months.len] - 1] {
-		day = ce.days[0]
-		month_index += 1
-
-		for day > time.month_days[ce.months[month_index & ce.months.len] - 1] {
-			month_index += 1
-
-			// If for whatever reason the day value ends up being something
-			// that can't be scheduled in any month, we have to make sure we
-			// don't create an infinite loop.
-			if month_index == 2 * ce.months.len {
-				return error('No schedulable moment.')
-			}
-		}
-	}
-
-	month := ce.months[month_index % ce.months.len]
-	mut year := sref.year
-
-	// If the month loops over, we need to increment the year.
-	if month_index >= ce.months.len {
-		year++
-	}
-
-	return time.new_time(time.Time{
-		year: year
-		month: month
-		day: day
-		minute: minute
-		hour: hour
-	})
-}
-
-// next_from_now returns the result of ce.next(ref) where ref is the result of
-// time.now().
-pub fn (ce &CronExpression) next_from_now() !time.Time {
-	return ce.next(time.now())
-}
-
-// next_n returns the n next occurences of the expression, given a starting
-// time.
-pub fn (ce &CronExpression) next_n(ref time.Time, n int) ![]time.Time {
-	mut times := []time.Time{cap: n}
-
-	times << ce.next(ref)!
-
-	for i in 1 .. n {
-		times << ce.next(times[i - 1])!
-	}
-
-	return times
-}
diff --git a/src/cron/expression/expression_parse.v b/src/cron/expression/expression_parse.v
deleted file mode 100644
index 4aaec5b..0000000
--- a/src/cron/expression/expression_parse.v
+++ /dev/null
@@ -1,146 +0,0 @@
-module expression
-
-import bitfield
-
-// parse_range parses a given string into a range of sorted integers. Its
-// result is a BitField with set bits for all numbers in the result.
-fn parse_range(s string, min int, max int) !bitfield.BitField {
-	mut start := min
-	mut end := max
-	mut interval := 1
-	mut bf := bitfield.new(max - min + 1)
-
-	exps := s.split('/')
-
-	if exps.len > 2 {
-		return error('Invalid expression.')
-	}
-
-	if exps[0] != '*' {
-		dash_parts := exps[0].split('-')
-
-		if dash_parts.len > 2 {
-			return error('Invalid expression.')
-		}
-
-		start = dash_parts[0].int()
-
-		// The builtin parsing functions return zero if the string can't be
-		// parsed into a number, so we have to explicitely check whether they
-		// actually entered zero or if it's an invalid number.
-		if start == 0 && dash_parts[0] != '0' {
-			return error('Invalid number.')
-		}
-
-		// Check whether the start value is out of range
-		if start < min || start > max {
-			return error('Out of range.')
-		}
-
-		if dash_parts.len == 2 {
-			end = dash_parts[1].int()
-
-			if end == 0 && dash_parts[1] != '0' {
-				return error('Invalid number.')
-			}
-
-			if end < start || end > max {
-				return error('Out of range.')
-			}
-		}
-	}
-
-	if exps.len > 1 {
-		interval = exps[1].int()
-
-		// interval being zero is always invalid, but we want to check why
-		// it's invalid for better error messages.
-		if interval == 0 {
-			if exps[1] != '0' {
-				return error('Invalid number.')
-			} else {
-				return error('Step size zero not allowed.')
-			}
-		}
-
-		if interval > max - min {
-			return error('Step size too large.')
-		}
-	}
-	// Here, s solely consists of a number, so that's the only value we
-	// should return.
-	else if exps[0] != '*' && !exps[0].contains('-') {
-		bf.set_bit(start - min)
-		return bf
-	}
-
-	for start <= end {
-		bf.set_bit(start - min)
-		start += interval
-	}
-
-	return bf
-}
-
-// bf_to_ints takes a BitField and converts it into the expected list of actual
-// integers.
-fn bf_to_ints(bf bitfield.BitField, min int) []int {
-	mut out := []int{}
-
-	for i in 0 .. bf.get_size() {
-		if bf.get_bit(i) == 1 {
-			out << min + i
-		}
-	}
-
-	return out
-}
-
-// parse_part parses a given part of a cron expression & returns the
-// corresponding array of ints.
-fn parse_part(s string, min int, max int) ![]int {
-	mut bf := bitfield.new(max - min + 1)
-
-	for range in s.split(',') {
-		bf2 := parse_range(range, min, max)!
-		bf = bitfield.bf_or(bf, bf2)
-	}
-
-	return bf_to_ints(bf, min)
-}
-
-// parse_expression parses an entire cron expression string into a
-// CronExpression object, if possible.
-pub fn parse_expression(exp string) !CronExpression {
-	// The filter allows for multiple spaces between parts
-	mut parts := exp.split(' ').filter(it != '')
-
-	if parts.len < 2 || parts.len > 4 {
-		return error('Expression must contain between 2 and 4 space-separated parts.')
-	}
-
-	// For ease of use, we allow the user to only specify as many parts as they
-	// need.
-	for parts.len < 4 {
-		parts << '*'
-	}
-
-	mut part_results := [][]int{}
-
-	mins := [0, 0, 1, 1]
-	maxs := [59, 23, 31, 12]
-
-	// This for loop allows us to more clearly propagate the error to the user.
-	for i, min in mins {
-		part_results << parse_part(parts[i], min, maxs[i]) or {
-			return error('An error occurred with part $i: $err.msg()')
-		}
-	}
-
-	return CronExpression{
-		minutes: part_results[0]
-		hours: part_results[1]
-		days: part_results[2]
-		months: part_results[3]
-	}
-}
diff --git a/src/cron/expression/expression_parse_test.v b/src/cron/expression/expression_parse_test.v
deleted file mode 100644
index 92e8291..0000000
--- a/src/cron/expression/expression_parse_test.v
+++ /dev/null
@@ -1,89 +0,0 @@
-module expression
-
-// parse_range_error returns the returned error message. If the result is '',
-// that means the function didn't error.
-fn parse_range_error(s string, min int, max int) string {
-	parse_range(s, min, max) or { return err.msg }
-
-	return ''
-}
-
-// =====parse_range=====
-fn test_range_star_range() ! {
-	bf := parse_range('*', 0, 5)!
-
-	assert bf_to_ints(bf, 0) == [0, 1, 2, 3, 4, 5]
-}
-
-fn test_range_number() ! {
-	bf := parse_range('4', 0, 5)!
-
-	assert bf_to_ints(bf, 0) == [4]
-}
-
-fn test_range_number_too_large() ! {
-	assert parse_range_error('10', 0, 6) == 'Out of range.'
-}
-
-fn test_range_number_too_small() ! {
-	assert parse_range_error('0', 2, 6) == 'Out of range.'
-}
-
-fn test_range_number_invalid() ! {
-	assert parse_range_error('x', 0, 6) == 'Invalid number.'
-}
-
-fn test_range_step_star_1() ! {
-	bf := parse_range('*/4', 0, 20)!
-
-	assert bf_to_ints(bf, 0) == [0, 4, 8, 12, 16, 20]
-}
-
-fn test_range_step_star_2() ! {
-	bf := parse_range('*/3', 1, 8)!
-
-	assert bf_to_ints(bf, 1) == [1, 4, 7]
-}
-
-fn test_range_step_star_too_large() ! {
-	assert parse_range_error('*/21', 0, 20) == 'Step size too large.'
-}
-
-fn test_range_step_zero() ! {
-	assert parse_range_error('*/0', 0, 20) == 'Step size zero not allowed.'
-}
-
-fn test_range_step_number() ! {
-	bf := parse_range('5/4', 2, 22)!
-
-	assert bf_to_ints(bf, 2) == [5, 9, 13, 17, 21]
-}
-
-fn test_range_step_number_too_large() ! {
-	assert parse_range_error('10/4', 0, 5) == 'Out of range.'
-}
-
-fn test_range_step_number_too_small() ! {
-	assert parse_range_error('2/4', 5, 10) == 'Out of range.'
-}
-
-fn test_range_dash() ! {
-	bf := parse_range('4-8', 0, 9)!
-
-	assert bf_to_ints(bf, 0) == [4, 5, 6, 7, 8]
-}
-
-fn test_range_dash_step() ! {
-	bf := parse_range('4-8/2', 0, 9)!
-
-	assert bf_to_ints(bf, 0) == [4, 6, 8]
-}
-
-// =====parse_part=====
-fn test_part_single() ! {
-	assert parse_part('*', 0, 5)! == [0, 1, 2, 3, 4, 5]
-}
-
-fn test_part_multiple() ! {
-	assert parse_part('*/2,2/3', 1, 8)! == [1, 2, 3, 5, 7, 8]
-}
diff --git a/src/cron/expression/expression_test.v b/src/cron/expression/expression_test.v
deleted file mode 100644
index 82bf959..0000000
--- a/src/cron/expression/expression_test.v
+++ /dev/null
@@ -1,34 +0,0 @@
-module expression
-
-import time { parse }
-
-fn util_test_time(exp string, t1_str string, t2_str string) ! {
-	ce := parse_expression(exp)!
-	t1 := parse(t1_str)!
-	t2 := parse(t2_str)!
-
-	t3 := ce.next(t1)!
-
-	assert t2.year == t3.year
-	assert t2.month == t3.month
-	assert t2.day == t3.day
-	assert t2.hour == t3.hour
-	assert t2.minute == t3.minute
-}
-
-fn test_next_simple() ! {
-	// Very simple
-	util_test_time('0 3', '2002-01-01 00:00:00', '2002-01-01 03:00:00')!
-
-	// Overlap to next day
-	util_test_time('0 3', '2002-01-01 03:00:00', '2002-01-02 03:00:00')!
-	util_test_time('0 3', '2002-01-01 04:00:00', '2002-01-02 03:00:00')!
-
-	util_test_time('0 3/4', '2002-01-01 04:00:00', '2002-01-01 07:00:00')!
-
-	// Overlap to next month
-	util_test_time('0 3', '2002-11-31 04:00:00', '2002-12-01 03:00:00')!
-
-	// Overlap to next year
-	util_test_time('0 3', '2002-12-31 04:00:00', '2003-01-01 03:00:00')!
-}
diff --git a/src/cron/expression_test.v b/src/cron/expression_test.v
new file mode 100644
index 0000000..4023012
--- /dev/null
+++ b/src/cron/expression_test.v
@@ -0,0 +1,46 @@
+module cron
+
+import time { parse }
+
+fn util_test_time(exp string, t1_str string, t2_str string) ! {
+	ce := parse_expression(exp)!
+	dump(ce)
+	t1 := parse(t1_str)!
+	t2 := parse(t2_str)!
+
+	t3 := ce.next(t1)
+
+	assert t2.year == t3.year
+	assert t2.month == t3.month
+	assert t2.day == t3.day
+	assert t2.hour == t3.hour
+	assert t2.minute == t3.minute
+}
+
+fn test_next_simple() ! {
+	// Very simple
+	// util_test_time('0 3', '2002-01-01 00:00:00', '2002-01-01 03:00:00')!
+
+	// Overlap to next day
+	mut exp := '0    3         '
+	util_test_time(exp, '2002-01-01 03:00:00', '2002-01-02 03:00:00')!
+	util_test_time(exp, '2002-01-01 04:00:00', '2002-01-02 03:00:00')!
+
+	util_test_time('0 3-7/4,7-19', '2002-01-01 04:00:00', '2002-01-01 07:00:00')!
+
+	//// Overlap to next month
+	util_test_time('0 3', '2002-11-31 04:00:00', '2002-12-01 03:00:00')!
+
+	//// Overlap to next year
+	util_test_time('0 3', '2002-12-31 04:00:00', '2003-01-01 03:00:00')!
+}
+
+fn test_leading_star() {
+	mut x := false
+	parse_expression('*5 8') or { x = true }
+	assert x
+
+	x = false
+	parse_expression('x 8') or { x = true }
+	assert x
+}
diff --git a/src/cron/v.mod b/src/cron/v.mod
new file mode 100644
index 0000000..e69de29
diff --git a/src/main.v b/src/main.v
index 1c8b816..ce9ec81 100644
--- a/src/main.v
+++ b/src/main.v
@@ -9,7 +9,6 @@ import console.schedule
 import console.man
 import console.aur
 import console.repos
-import cron
 import agent
 
 fn main() {
@@ -43,7 +42,6 @@ fn main() {
 		commands: [
 			server.cmd(),
 			targets.cmd(),
-			cron.cmd(),
 			logs.cmd(),
 			schedule.cmd(),
 			man.cmd(),
diff --git a/src/server/log_removal.v b/src/server/log_removal.v
index 8e1a8c2..7f1cfb5 100644
--- a/src/server/log_removal.v
+++ b/src/server/log_removal.v
@@ -3,17 +3,13 @@ module server
 import time
 import models { BuildLog }
 import os
-import cron.expression { CronExpression }
+import cron
 
 const fallback_log_removal_frequency = 24 * time.hour
 
 // log_removal_daemon removes old build logs every `log_removal_frequency`.
-fn (mut app App) log_removal_daemon(schedule CronExpression) {
-	mut start_time := time.Time{}
-
+fn (mut app App) log_removal_daemon(schedule cron.Expression) {
 	for {
-		start_time = time.now()
-
 		mut too_old_timestamp := time.now().add_days(-app.conf.max_log_age)
 
 		app.linfo('Cleaning logs before $too_old_timestamp')
@@ -51,12 +47,7 @@ fn (mut app App) log_removal_daemon(schedule CronExpression) {
 		app.linfo('Cleaned $counter logs ($failed failed)')
 
 		// Sleep until the next cycle
-		next_time := schedule.next_from_now() or {
-			app.lerror("Log removal daemon couldn't calculate next time: $err.msg(); fallback to $server.fallback_log_removal_frequency")
-
-			start_time.add(server.fallback_log_removal_frequency)
-		}
-
+		next_time := schedule.next_from_now()
 		time.sleep(next_time - time.now())
 	}
 }
diff --git a/src/server/server.v b/src/server/server.v
index 5dd1a20..ae086f5 100644
--- a/src/server/server.v
+++ b/src/server/server.v
@@ -7,7 +7,7 @@ import repo
 import util
 import db
 import build { BuildJobQueue }
-import cron.expression
+import cron
 import metrics
 
 const (
@@ -43,11 +43,11 @@ pub fn server(conf Config) ! {
 		util.exit_with_message(1, "'any' is not allowed as the value for default_arch.")
 	}
 
-	global_ce := expression.parse_expression(conf.global_schedule) or {
+	global_ce := cron.parse_expression(conf.global_schedule) or {
 		util.exit_with_message(1, 'Invalid global cron expression: $err.msg()')
 	}
 
-	log_removal_ce := expression.parse_expression(conf.log_removal_schedule) or {
+	log_removal_ce := cron.parse_expression(conf.log_removal_schedule) or {
 		util.exit_with_message(1, 'Invalid log removal cron expression: $err.msg()')
 	}