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diff --git a/_archive/arduino-due.md b/_archive/arduino-due.md
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--- a/_archive/arduino-due.md
+++ /dev/null
@@ -1,122 +0,0 @@
----
-title: How to set up ATSAM3X8E microcontrollers for bare-metal programming in C
-date: 2024-10-05
-layout: post
----
-
-This article is a step-by-step guide for programming bare-metal ATSAM3X8E chips
-found on Arduino Due boards. It also includes notes on the chip's memory layout
-relevant for writing linker scripts. The steps described in this article were
-tested on an OpenBSD workstation.
-
-## Toolchain
-
-To interact directly with a bare-metal ATSAM3X8E chips, we must bypass the
-embedded bootloader. To do that, we need a hardware programmer capable of
-communicating with the chip over the Serial Wire Debug (SWD) protocol. Since
-the workstation we upload the program from presumably doesn't speak SWD, the
-hardware programmer acts as a SWD-USB adapter. The <a
-href="https://www.st.com/en/development-tools/st-link-v2.html" class="external"
-target="_blank" rel="noopener noreferrer">ST-LINK/V2</a> programmer fits this
-bill.
-
-The <a href="https://openocd.org/" class="external" target="_blank"
-rel="noopener noreferrer">OpenOCD</a> on-chip debugger software supports
-ATSAM3X8E chips. OpenOCD, on startup, runs a telnet server that we can connect to
-to issue commands to the ATSAM3X8E chip. OpenOCD translates plain-text commands
-into the binary sequences the chip understands, and sends them over the wire.
-
-Finally, we need the <a
-href="https://developer.arm.com/Tools%20and%20Software/GNU%20Toolchain"
-class="external" target="_blank" rel="noopener noreferrer">ARM GNU Compiler
-Toolchain</a> to compile C programs for the chip. The ARM GNU compiler
-toolchain and OpenOCD, as a consequence of being free software, are available 
-on every conceivable platform, including OpenBSD.
-
-## Electrical connections
-
-The following photos illustrate the electrical connections between the Arduino
-Due, PC, and the ST-LINK/V2 programmer required to transfer a compiled program
-from a PC to the MCU.
-
-<table style="border: none; width: 100%;">
-  <tr style="border: none;">
-    <td style="border: none; width: 50%; vertical-align: top; background-color: transparent;">
-      <img src="schematic.png" alt="Pinout" style="width: 100%">
-      <p style="text-align: center;">Wiring</p>
-    </td>
-    <td style="border: none; width: 50%; vertical-align: top; background-color: transparent;">
-      <img src="connections.jpeg" alt="Circuit" style="width: 100%">
-      <p style="text-align: center;">Arduino Due</p>
-    </td>
-  </tr>
-</table>
-
-Arduino Due exposes the ATSAM3X8E's SWD interface via its DEBUG port. The
-ST-LINK/v2 programmer connects to that to communicate with the chip.
-
-## Uploading the program
-
-The source.tar.gz tarball at the end of this page contains a sample C program
-(the classic LED blink program) with OpenOCD configuration and linker scripts.
-First, use the following command to build it:
-
-```
-$ arm-none-eabi-gcc -mcpu=cortex-m3 -mthumb -T script.ld \
-    -nostartfiles \
-    -nostdlib \
-    -o a.elf main.c
-```
-
-Then, open a telnet session with OpenOCD and issue the following sequence of
-commands to configure the chip and upload the compiled program to it:
-
-```
-$ openocd -f openocd-due.cfg
-$ telnet localhost 4444
-  > halt
-  > at91sam3 gpnvm show
-  > at91sam3 gpnvm set 1
-  > at91sam3 gpnvm show
-$ openocd -f openocd-due.cfg -c "program a.elf verify reset exit"
-```
-
-The first of the above commands starts OpenOCD. In the telnet session, the
-first command halts the chip in preparation for receiving commands. Next, we
-inspect the current GPNVM bit setting (more on this later). If the bit is unset
-(the gpnvm show command returns 0), we set it to 1 and verify the update.
-
-The final command, issued from outside the telnet session, uploads the program
-to the chip. Those are the bare minimum set of commands required to program the
-chip. The AT91SAM3 flash driver section of the OpenOCD manual lists all
-available commands for the ATSAM3X8E chip.
-
-## GPNVM bits
-
-By design, ARM chips boot into address 0x00000. ATSAM3X8E's memory consists of
-a ROM and a dual-banked flash (flash0 and flash1), residing in different
-locations of the chip's address space. The GPNVM bits control which of them
-maps to 0x00000. When GPNVM1 is cleared (the default), the chip boots from the ROM,
-which contains Atmel's SAM-BA bootloader.
-
-Conversely, when the GPNVM1 bit is 1 (and the GPNVM2 bit is 0), flash0 at
-address 0x80000 maps to 0x00000. When both GPNVM bits are 0, flash1 maps to
-0x00000. Since we place our program in flash0 in the linker script, we set the
-GPNVM1 bit and leave the GPNVM2 bit unchanged to ensure the chip
-executes our program instead of the embedded bootloader at startup.
-
-## Linker script
-
-At a minimum, the linker script must place the vector table at the first
-address of the flash. This is mandatory for ARM chips unless we relocate the
-vector table using the VTOR register. 
-
-The first entry of the vector table must be the stack pointer. The stack
-pointer must be initializes to the highest memory location available to
-accommodate the ATSAM3X8E's descending stack.
-
-The second entry of the vector table must be the reset vector. In the reset
-vector, we can perform tasks such as zeroing out memory and initializing
-registers before passing control to the main program.
-
-Files: [source.tar.gz](source.tar.gz)
diff --git a/_archive/arduino-due/connections.jpeg b/_archive/arduino-due/connections.jpeg
deleted file mode 100644
index 081e6d4..0000000
--- a/_archive/arduino-due/connections.jpeg
+++ /dev/null
diff --git a/_archive/arduino-due/schematic.png b/_archive/arduino-due/schematic.png
deleted file mode 100644
index 62ddadd..0000000
--- a/_archive/arduino-due/schematic.png
+++ /dev/null
diff --git a/_archive/arduino-due/source.tar.gz b/_archive/arduino-due/source.tar.gz
deleted file mode 100644
index 496567b..0000000
--- a/_archive/arduino-due/source.tar.gz
+++ /dev/null
diff --git a/_archive/arduino-uno.md b/_archive/arduino-uno.md
deleted file mode 100644
index 6534c3c..0000000
--- a/_archive/arduino-uno.md
+++ /dev/null
@@ -1,82 +0,0 @@
----
-title: How to configure ATmega328P microcontrollers to run at 3.3V and 5V
-date: 2025-04-10
-layout: post
----
-
-This is a quick reference for wiring up ATmega328P ICs to run at 5V and 3.3V.
-While the 5V configuration is common, the 3.3V configuration can be useful in
-low-power applications and when interfacing with parts that themselves run at
-3.3V. In this guide, the 5V setup is configured with a 16MHz crystal
-oscillator, while the 3.3V configuration makes use of an 8MHz crystal
-oscillator. 
-
-The steps that follow refer to the following pinout.
-
-<table style="border: none; width: 100%;">
-  <tr style="border: none;">
-    <td style="border: none; width: 50%; vertical-align: top;">
-      <img src="pinout.png" alt="Pinout" style="width: 100%">
-      <p style="text-align: center;">Pinout</p>
-    </td>
-    <td style="border: none; width: 50%; vertical-align: top;">
-      <img src="breadboard.jpeg" alt="Circuit" style="width: 100%">
-      <p style="text-align: center;">Breadboard</p>
-    </td>
-  </tr>
-</table>
-
-## 5V-16MHz configuration 
-
-Powering ATmega328P microcontrollers with 5V is the most common setup. This is
-also how Arduino Uno boards are wired.
-
-In this configuration, the microcontroller's pin 1 is connected to 5V via a
-10kΩ resistor. Pins 9 and 10 are connected to a 16MHz crystal oscillator via
-two 22pF capacitors connected to ground. The microcontroller is powered by
-connecting pins 7, 20, and 21 to a 5V DC power supply. Lastly, pins 8 and 22
-are connected to ground. In addition to the these connections, which are
-required, it's a good idea to add 0.1μF decoupling capacitors between pins 7,
-20, and 21 and ground. 
-
-[Here's](Makefile) a sample Makefile for compiling C programs for ATmega328P
-microcontrollers using avr-gcc/avrdude toolchain.
-
-## 3.3V-8MHz configuration 
-
-Electrical connections for running an ATmega328P at 3.3V are identical to that
-of the 5V circuit. The only differences are that all the 5V connections are
-replaced with a 3.3V power source and a 8MHz crystal oscillator takes the place
-of the 16MHz crystal.
-
-However, standard ATmega328P chips are preconfigured to run at 5V. To run one
-at 3.3V, we must first modify its fuses that control characteristics like the
-BOD level. If a bootloader that expects a 16MHz clock (e.g., Arduino
-bootloader) is pre-installed on the ATmega328P, it must be swapped with one
-that accepts an 8MHz clock. To accomplish that, we need an in-system programmer
-(ISP). 
-
-Fortunately, we can turn an ordinary Arduino Uno board into an ISP by uploading
-the 'ArduinoISP' sketch found in the Arduino IDE. The ISP communicates with the
-microcontroller using a Serial Peripheral Interface (SPI). So, connect the SPI
-port of the ATmega328P to that of the Arduino Uno, and the Uno's SS pin
-to the ATmega328P's RESET pin.
-
-Power up the the ATmega328P by connecting its V<sub>CC</sub> to a 5V supply (we
-can use Arduino Uno's 5V pin). From the Arduino IDE, select 'ATmega328P (3.3V,
-8MHz)' for processor from the tools menu. Also from the tools menu, select
-'Arduino as ISP' as programmer. Finally, upload the new bootloader by selecting
-'Burn Bootloader' from the tools menu.
-
-The ATmega328P is now ready to run at 8MHz with a 3.3V power supply. You can
-upload programs to the ATmega328P as you normally would using avrdude.
-[Here's](3v3.Makefile) a sample Makefile with adjusted parameters (e.g., baud
-rate) for an 8MHz clock.
-
-## Remarks
-
-In both configurations, if you intend to use the ATmega328P's analog-to-digital
-converter with the internal 1.1V or AV<sub>cc</sub> voltage as reference, do
-not connect AREF (pin 21) to V<sub>cc</sub>. Refer to section 23.5.2 in the
-datasheet for more information.
-
diff --git a/_archive/arduino-uno/3v3.Makefile b/_archive/arduino-uno/3v3.Makefile
deleted file mode 100644
index 4ca89d4..0000000
--- a/_archive/arduino-uno/3v3.Makefile
+++ /dev/null
@@ -1,46 +0,0 @@
-CC = avr-gcc
-MCU = atmega328p
-PORT = /dev/cuaU0
-TARGET = app
-
-SRC = main.c
-OBJ = $(SRC:.c=.o)
-
-CFLAGS = -std=gnu99
-CFLAGS += -Os
-CFLAGS += -Wall
-CFLAGS += -mmcu=$(MCU)
-CFLAGS += -DBAUD=57600
-CFLAGS += -DF_CPU=8000000UL
-CFLAGS += -ffunction-sections -fdata-sections
-
-LDFLAGS = -mmcu=$(MCU)
-LDFLAGS += -Wl,--gc-sections
-
-HEX_FLAGS = -O ihex
-HEX_FLAGS += -j .text -j .data
-
-AVRDUDE_FLAGS = -p $(MCU)
-AVRDUDE_FLAGS += -c arduino
-AVRDUDE_FLAGS += -b 57600
-AVRDUDE_FLAGS += -P $(PORT)
-AVRDUDE_FLAGS += -D -U
-
-%.o: %.c
-	 $(CC) $(CFLAGS) -c -o $@ $<
-
-elf: $(OBJ)
-	 $(CC) $(LDFLAGS) $(OBJ) -o $(TARGET).elf
-
-hex: elf
-	 avr-objcopy $(HEX_FLAGS) $(TARGET).elf $(TARGET).hex
-
-upload: hex
-	 avrdude $(AVRDUDE_FLAGS) flash:w:$(TARGET).hex:i
-
-.PHONY: clean
-
-clean:
-	 rm -f *.o *.elf *.hex 
-
-
diff --git a/_archive/arduino-uno/Makefile b/_archive/arduino-uno/Makefile
deleted file mode 100644
index 9db7b09..0000000
--- a/_archive/arduino-uno/Makefile
+++ /dev/null
@@ -1,43 +0,0 @@
-CC     = avr-gcc
-MCU    = atmega328p
-PORT   = /dev/cuaU0
-TARGET = app
-
-SRC = main.c
-OBJ = $(SRC:.c=.o)
-
-CFLAGS = -std=gnu99
-CFLAGS += -Os
-CFLAGS += -Wall
-CFLAGS += -mmcu=$(MCU)
-CFLAGS += -DBAUD=115200
-CFLAGS += -DF_CPU=16000000UL
-CFLAGS += -ffunction-sections -fdata-sections
-
-LDFLAGS = -mmcu=$(MCU)
-LDFLAGS += -Wl,--gc-sections
-
-HEX_FLAGS = -O ihex
-HEX_FLAGS += -j .text -j .data
-
-AVRDUDE_FLAGS = -p $(MCU)
-AVRDUDE_FLAGS += -c arduino
-AVRDUDE_FLAGS += -P $(PORT)
-AVRDUDE_FLAGS += -D -U
-
-%.o: %.c
-	 $(CC) $(CFLAGS) -c -o $@ $<
-
-elf: $(OBJ)
-	 $(CC) $(LDFLAGS) $(OBJ) -o $(TARGET).elf
-
-hex: elf
-	 avr-objcopy $(HEX_FLAGS) $(TARGET).elf $(TARGET).hex
-
-upload: hex
-	 avrdude $(AVRDUDE_FLAGS) flash:w:$(TARGET).hex:i
-
-.PHONY: clean
-
-clean:
-	 rm *.o *.elf *.hex 
diff --git a/_archive/arduino-uno/breadboard.jpeg b/_archive/arduino-uno/breadboard.jpeg
deleted file mode 100644
index bd74907..0000000
--- a/_archive/arduino-uno/breadboard.jpeg
+++ /dev/null
diff --git a/_archive/arduino-uno/pinout.png b/_archive/arduino-uno/pinout.png
deleted file mode 100644
index 59acfbc..0000000
--- a/_archive/arduino-uno/pinout.png
+++ /dev/null
diff --git a/_archive/mosfet-switches.md b/_archive/mosfet-switches.md
deleted file mode 100644
index bb3514d..0000000
--- a/_archive/mosfet-switches.md
+++ /dev/null
@@ -1,123 +0,0 @@
----
-title: MOSFETs as electronic switches
-date: 2025-06-22
-layout: post
----
-
-Recently, I needed a low-power circuit for one of my battery-operated projects.
-Much of the system's power savings depended on its ability to electronically
-switch off components, such as servos, that draw high levels of quiescent
-currents. My search for a solution led me to MOSFETs, transistors capable of
-controlling circuits operating at voltages far above their own.
-
-## Acknowledgments
-
-This article is a summary of what I learnt about using MOSFETs as switches.
-I'm not an electronics engineer, and this is not an authoritative guide. The
-circuits in this post must be considered within the narrow context in which
-I've used them. All credits for the schematics belong to <a
-href="https://electronics.stackexchange.com/users/292884/simon-fitch"
-class="external" target="_blank" rel="noopener noreferrer">Simon Fitch</a>. 
-
-## Preamble
-
-For a typical MOSFET-based switch, we can connect a GPIO pin of a
-microcontroller to the gate of a logic-level N-channel MOSFET placed on the low
-side of the load and tie the gate and the drain pins of the MOSFET with a
-pull-down resistor. This would work as long as the power supplies of the
-microcontroller and the load don't share a common ground. Things become more
-complicated when they do (e.g., controlling power to a component driven by the
-same microcontroller).
-
-In that scenario, the source potential visible to the load is the difference
-between the gate and the threshold potentials of the MOSFET. For example, when
-the gate and the threshold potentials are 3.3 V and 1.5 V, the potential the
-load sees is 1.8 V. So, to use a low-side N-channel MOSFET, we need the gate
-potential to be higher than the source potential, which may not always be
-practical. The alternative would be a hide-side switch.
-
-## P-channel high-side switch
-
-The following schematic shows how a high-side P-channel MOSFET (M1) could
-switch power to a 6 V servo driven by a 3.3 V MCU.
-
-![P-channel high-side switching circuit](p_high_side.png)
-
-When the microcontroller outputs low, the M2 N-channel MOSFET stops conducting.
-The R1 resistor pulls the gate of the M1 P-channel MOSFET up to +6 V, switching
-the servo off. When the microcontroller outputs high on the GPIO pin, M2's
-source-drain connection starts conducting, causing M1's gate potential to drop
-to 0 V, which switches on power to the servo. 
-
-## N-channel high-side switch
-
-The P-channel high-side switch would be the typical architecture for our use
-case. However, if we have access to a potential high enough to safely raise the
-gate potential above the threshold such that their difference outputs the source
-potential required to drive the load, we can switch on the high side using an
-N-channel MOSFET:
-
-![N-channel high-side switching circuit](n_high_side.png)
-
-In the schematic, both M1 and M2 are N-channel MOSFETs. When the
-microcontroller output is low, M2 stops conducting. This causes the M1's gate
-potential to rise above the threshold, turning the servo on. Conversely, a high
-output on the GPIO line switches M2 on, which lowers M1's gate potential. This
-switches the servo off. The R2 pull-up resistor prevents the high impedance of
-the output pins at power-up from switching the servo on.
-
-Both topologies require M2 to act as a level converter between circuits
-containing the microcontroller and the servo, converting between 0 V and +6 V
-or +9 V. M2 is a low-power signal converter carrying less than a milliamp of
-current. The gate-source threshold voltage of M2 must be lower than the MCU's
-supply voltage. 2N7000, 2N7002, and BSS138 are popular choices for M2.
-
-The D1 flyback diodes used in the two topologies safeguard the MOSFET from
-voltage spikes caused by inductive loads such as servos.
-
-## A BJT alternative
-
-A Bipolar Junction Transistor (BJT) is a simpler, cheaper, and more widely
-available type of transistor that can be used as a switch.
-
-![BJT architecture](bjt.png)
-
-In the schematic, when the MCU outputs high, Q2 starts conducting. Q2 amplifies
-Q1's base current. Unlike MOSFETs, which are voltage-driven, BJTs are driven by
-base current. Resistors R3 and R4 must be chosen carefully to output the
-desired base currents. <a
-href="https://teachmetomake.wordpress.com/how-to-use-a-transistor-as-a-switch/"
-class="external" target="_blank" rel="noopener noreferrer">"How to choose a
-transistor as a switch"</a> is an excellent guide on using BJTs as electronic 
-switches.
-
-## Which topology to choose?
-
-The professional community appears to prefer MOSFETs over BJTs. MOSFETs are
-more efficient when the switch is on. However, they are more challenging to
-drive, especially with a 3.3 V MCU, due to the V<sub>GS</sub> potentials
-required to achieve specified R<sub>DS(on)</sub> values (i.e., to turn them on
-fully).
-
-N-channel MOSFETs have lower on-resistance values, making them more efficient
-than P-channel ones. They are also cheaper. However, they are harder to drive
-on the high side as their gate potential must be higher than the source
-potential. This often requires extra circuitry such as MOSFET drivers.
-
-## Further reading
-
- - <a href="https://www.embeddedrelated.com/showarticle/98.php"
-   class="external" target="_blank" rel="noopener noreferrer">Different MOSFET
-   topologies</a>
- - <a href="https://www.embeddedrelated.com/showarticle/809.php"
-   class="external" target="_blank" rel="noopener noreferrer">How to read 
-   MOSFET datasheets</a>
- - <a src="https://teachmetomake.wordpress.com/how-to-use-a-transistor-as-a-switch/"
-   class="external" target="_blank" rel="noopener noreferrer">How to use a 
-   transistor as a switch</a>
- - <a src="https://forum.digikey.com/t/guide-to-selecting-and-controlling-a-mosfet-for-3-3-vdc-logic-applications/42606"
-   class="external" target="_blank" rel="noopener noreferrer">Guide to 
-   selecting and controlling a MOSFET for 3.3 VDC logic applications</a>
- - <a src="https://forum.digikey.com/t/driving-a-large-relay-from-a-3-3-vdc-microcontroller-using-an-npn-darlington-transistor/41751"
-   class="external" target="_blank" rel="noopener noreferrer">Driving a large 
-   relay from a 3.3 VDC microcontroller using an NPN Darlington transistor</a>
diff --git a/_archive/mosfet-switches/bjt.png b/_archive/mosfet-switches/bjt.png
deleted file mode 100644
index 9858fa7..0000000
--- a/_archive/mosfet-switches/bjt.png
+++ /dev/null
diff --git a/_archive/mosfet-switches/n_high_side.png b/_archive/mosfet-switches/n_high_side.png
deleted file mode 100644
index c851768..0000000
--- a/_archive/mosfet-switches/n_high_side.png
+++ /dev/null
diff --git a/_archive/mosfet-switches/p_high_side.png b/_archive/mosfet-switches/p_high_side.png
deleted file mode 100644
index 9f5397a..0000000
--- a/_archive/mosfet-switches/p_high_side.png
+++ /dev/null
diff --git a/_archive/neo4j-a-star-search.md b/_archive/neo4j-a-star-search.md
deleted file mode 100644
index 117931b..0000000
--- a/_archive/neo4j-a-star-search.md
+++ /dev/null
@@ -1,318 +0,0 @@
----
-title: Neo4J A* search
-date: 2025-09-14
-layout: post
----
-
-Back in 2018, we used <a href="https://neo4j.com/" class="external"
-target="_blank" rel="noopener noreferrer">Neo4J</a> graph database to track the
-movement of marine vessels. We were interested in the shortest path a ship
-could take through a network of about 13,000 route points. Algorithms based on
-graph theory, such as A* search, provide optimal solutions to such problems.
-In other words, the set of route points lends itself well to a model based on
-graphs.
-
-A graph is a finite set of vertices, and a subset of vertex pairs (edges).
-Edges can have weights. In the case of vessel tracking, the route points form
-the vertices of a graph; the routes between them, the edges; and the distances
-between them are the weights. For different reasons, people are interested in
-minimizing (or maximizing) the weight of a path through a set of vertices. For
-instance, we may want to find the shortest path between two ports.
-
-Given such a graph, an algorithm like Dijkstra's search could compute the
-shortest path between two vertices. In fact, this was the algorithm Neo4J
-shipped with at the time. One drawback of Dijkstra's algorithm is that it
-computes all the shortest paths from the source to all other vertices before
-terminating at the destination vertex. The exhaustive nature of this search
-limited our search to about 4,000 route points.
-
-The following enhancement to Dijkstra's search, also known as the A* search,
-employs a heuristic to steer the search in the direction of the destination
-more quickly. In the case of our network of vessels, which are on the earth's
-surface, spherical distance is a good candidate for a heuristic:
-
-```
-package org.neo4j.graphalgo.impl;
-
-import java.util.stream.Stream;
-import java.util.stream.StreamSupport;
-
-import org.neo4j.graphalgo.api.Graph;
-import org.neo4j.graphalgo.core.utils.ProgressLogger;
-import org.neo4j.graphalgo.core.utils.queue.IntPriorityQueue;
-import org.neo4j.graphalgo.core.utils.queue.SharedIntPriorityQueue;
-import org.neo4j.graphalgo.core.utils.traverse.SimpleBitSet;
-import org.neo4j.graphdb.Direction;
-import org.neo4j.graphdb.Node;
-import org.neo4j.kernel.internal.GraphDatabaseAPI;
-
-import com.carrotsearch.hppc.IntArrayDeque;
-import com.carrotsearch.hppc.IntDoubleMap;
-import com.carrotsearch.hppc.IntDoubleScatterMap;
-import com.carrotsearch.hppc.IntIntMap;
-import com.carrotsearch.hppc.IntIntScatterMap;
-
-public class ShortestPathAStar extends Algorithm<ShortestPathAStar> {
-    
-    private final GraphDatabaseAPI dbService;
-    private static final int PATH_END = -1;
-    
-    private Graph graph;
-    private final int nodeCount;
-    private IntDoubleMap gCosts;
-    private IntDoubleMap fCosts;
-    private double totalCost;
-    private IntPriorityQueue openNodes;
-    private IntIntMap path;
-    private IntArrayDeque shortestPath;
-    private SimpleBitSet closedNodes;
-    private final ProgressLogger progressLogger;
-    
-    public static final double NO_PATH_FOUND = -1.0;
-    
-    public ShortestPathAStar(
-        final Graph graph,
-        final GraphDatabaseAPI dbService) {
-
-        this.graph = graph;
-        this.dbService = dbService;
-
-        nodeCount = Math.toIntExact(graph.nodeCount());
-        gCosts = new IntDoubleScatterMap(nodeCount);
-        fCosts = new IntDoubleScatterMap(nodeCount);
-        openNodes = SharedIntPriorityQueue.min(
-            nodeCount,
-            fCosts,
-            Double.MAX_VALUE);
-        path = new IntIntScatterMap(nodeCount);
-        closedNodes = new SimpleBitSet(nodeCount);
-        shortestPath = new IntArrayDeque();
-        progressLogger = getProgressLogger();
-    }
-    
-    public ShortestPathAStar compute(
-        final long startNode,
-        final long goalNode,
-        final String propertyKeyLat,
-        final String propertyKeyLon,
-        final Direction direction) {
-
-        reset();
-
-        final int startNodeInternal = 
-            graph.toMappedNodeId(startNode);
-        final double startNodeLat =
-            getNodeCoordinate(startNodeInternal, propertyKeyLat);
-        final double startNodeLon = 
-            getNodeCoordinate(startNodeInternal, propertyKeyLon);
-
-        final int goalNodeInternal =
-            graph.toMappedNodeId(goalNode);
-        final double goalNodeLat = 
-            getNodeCoordinate(goalNodeInternal, propertyKeyLat);
-        final double goalNodeLon = 
-            getNodeCoordinate(goalNodeInternal, propertyKeyLon);
-
-        final double initialHeuristic = 
-            computeHeuristic(startNodeLat,
-                startNodeLon,
-                goalNodeLat,
-                goalNodeLon);
-
-        gCosts.put(startNodeInternal, 0.0);
-        fCosts.put(startNodeInternal, initialHeuristic);
-        openNodes.add(startNodeInternal, 0.0);
-
-        run(goalNodeInternal,
-            propertyKeyLat,
-            propertyKeyLon,
-            direction);
-
-        if (path.containsKey(goalNodeInternal)) {
-            totalCost = gCosts.get(goalNodeInternal);
-            int node = goalNodeInternal;
-            while (node != PATH_END) {
-                shortestPath.addFirst(node);
-                node = path.getOrDefault(node, PATH_END);
-            }
-        }
-        return this;
-    }
-    
-    private void run(
-        final int goalNodeId,
-        final String propertyKeyLat,
-        final String propertyKeyLon,
-        final Direction direction) {
-
-        final double goalLat = 
-            getNodeCoordinate(goalNodeId, propertyKeyLat);
-        final double goalLon =
-            getNodeCoordinate(goalNodeId, propertyKeyLon);
-
-        while (!openNodes.isEmpty() && running()) {
-            int currentNodeId = openNodes.pop();
-            if (currentNodeId == goalNodeId) {
-                return;
-            }
-
-            closedNodes.put(currentNodeId);
-
-            double currentNodeCost = 
-                this.gCosts.getOrDefault(
-                    currentNodeId, 
-                    Double.MAX_VALUE);
-
-            graph.forEachRelationship(
-                currentNodeId,
-                direction,
-                (source, target, relationshipId, weight) -> {
-                    double neighbourLat = 
-                        getNodeCoordinate(target, propertyKeyLat);
-                    double neighbourLon = 
-                        getNodeCoordinate(target, propertyKeyLon);
-                    double heuristic = 
-                        computeHeuristic(
-                            neighbourLat, 
-                            neighbourLon, 
-                            goalLat,
-                            goalLon);
-
-                    updateCosts(
-                        source,
-                        target,
-                        weight + currentNodeCost,
-                        heuristic);
-
-                    if (!closedNodes.contains(target)) {
-                        openNodes.add(target, 0);
-                    }
-                    return true;
-                });
-
-            progressLogger.logProgress(
-                (double) currentNodeId / (nodeCount - 1));
-        }
-    }
-    
-    private double computeHeuristic(
-        final double lat1,
-        final double lon1,
-        final double lat2,
-        final double lon2) {
-
-        final int earthRadius = 6371;
-        final double kmToNM = 0.539957;
-        final double latDistance = Math.toRadians(lat2 - lat1);
-        final double lonDistance = Math.toRadians(lon2 - lon1);
-        final double a = Math.sin(latDistance / 2)
-            * Math.sin(latDistance / 2)
-            + Math.cos(Math.toRadians(lat1))
-            * Math.cos(Math.toRadians(lat2))
-            * Math.sin(lonDistance / 2)
-            * Math.sin(lonDistance / 2);
-        final double c = 2
-            * Math.atan2(Math.sqrt(a), Math.sqrt(1 - a));
-        final double distance = earthRadius * c * kmToNM;
-        return distance;
-    }
-    
-    private double getNodeCoordinate(
-        final int nodeId,
-        final String coordinateType) {
-
-        final long neo4jId = graph.toOriginalNodeId(nodeId);
-        final Node node = dbService.getNodeById(neo4jId);
-        return (double) node.getProperty(coordinateType);
-    }
-    
-    private void updateCosts(
-        final int source, 
-        final int target, 
-        final double newCost,
-        final double heuristic) {
-
-        final double oldCost = 
-            gCosts.getOrDefault(target, Double.MAX_VALUE);
-
-        if (newCost < oldCost) {
-            gCosts.put(target, newCost);
-            fCosts.put(target, newCost + heuristic);
-            path.put(target, source);
-        }
-    }
-    
-    private void reset() {
-        closedNodes.clear();
-        openNodes.clear();
-        gCosts.clear();
-        fCosts.clear();
-        path.clear();
-        shortestPath.clear();
-        totalCost = NO_PATH_FOUND;
-    }
-    
-    public Stream<Result> resultStream() {
-        return StreamSupport.stream(
-            shortestPath.spliterator(), false)
-                .map(cursor -> new Result(
-                    graph.toOriginalNodeId(cursor.value),
-                    gCosts.get(cursor.value)));
-    }
-
-    public IntArrayDeque getFinalPath() {
-        return shortestPath;
-    }
-    
-    public double getTotalCost() {
-        return totalCost;
-    }
-
-    public int getPathLength() {
-        return shortestPath.size();
-    }
-    
-    @Override
-    public ShortestPathAStar me() {
-        return this;
-    }
-
-    @Override
-    public ShortestPathAStar release() {
-        graph = null;
-        gCosts = null;
-        fCosts = null;
-        openNodes = null;
-        path = null;
-        shortestPath = null;
-        closedNodes = null;
-        return this;
-    }
-    
-    public static class Result {
-
-        /**
-         * the neo4j node id
-         */
-        public final Long nodeId;
-
-        /**
-         * cost to reach the node from startNode
-         */
-        public final Double cost;
-
-        public Result(Long nodeId, Double cost) {
-            this.nodeId = nodeId;
-            this.cost = cost;
-        }
-    }
-}
-```
-
-The heuristic function is domain-specific. If chosen wisely, it can
-significantly speed up the search. In our case, we achieved a 300x speedup,
-enabling us to expand our search from 4,000 to 13,000 route points. The <a
-href="https://github.com/neo4j-contrib/neo4j-graph-algorithms/releases/tag/3.4.0.0"
-class="external" target="_blank" rel="noopener noreferrer">v3.4.0</a> of the
-Neo4J graph algorithms shipped with the A* search algorithm.
-
diff --git a/_archive/suckless-software.md b/_archive/suckless-software.md
deleted file mode 100644
index 86fb5bc..0000000
--- a/_archive/suckless-software.md
+++ /dev/null
@@ -1,90 +0,0 @@
----
-title: How I manage Suckless software packages
-date: 2025-11-30
-layout: post
----
-
-Since <a href="https://suckless.org/" class="external" target="_blank"
-rel="noopener noreferrer">suckless</a> software requires users to modify the
-source code and recompile to customize, I need a way to maintain patches over
-the long term while retaining the ability to upgrade the software as new
-versions are released.
-
-## Initial setup
-
-When using a suckless program, I usually begin by cloning the project and
-setting the remote URL to push a copy of the source code with my patches to my
-own git repository:
-
-```
-git clone git://git.suckless.org/dwm
-git reset --hard <tag>
-git remote set-url --push origin git@git.asciimx.com:/repos/dwm
-```
-
-This way, I can pull updates from the upstream project whenever I want, while
-committing my changes to my own git repository. The git reset command aligns my
-branch head with a stable release before applying patches or installing the
-software.
-
-If all I want to do is reconfigure the software (e.g., change key bindings),
-which is what I need most of the time, the recommended approach is to modify
-the config.h file. If the config.h isn't yet in the project, the following
-command generates it from the defaults and compiles the software using `make
-clean <target>` here `<target>` is the name of the application (e.g., dwm)
-found in the Makefile. I modify the resulting config.h file and run `make clean
-install` to install the software before committing and pushing my changes to my
-git repo.
-
-## dwm and slstatus
-
-Since dwm and slstatus are always running, `make install` will likely fail for
-them. The operating system will prevent the installer from replacing running
-executables with new ones. Hence, we must first stop the running instances of
-these programs (Mod + Shift + q). Then, switch to a tty (Ctrl + Alt + F1),
-log in, and change the directory to where dwm/slstatus is. We can run `make
-install` to install the software and switch back to the graphical session
-(Ctrl + Alt + F5).
-
-The key combinations for switching to the tty and back may differ across
-systems. The ones listed above are for OpenBSD.
-
-## Subsequent upgrades
-
-When suckless releases a new version, I run `git pull --rebase` to fetch the
-upstream changes and rebase my patches on top of them. Because I tend to use
-stable versions, I perform another interactive rebase to drop the commits
-between the latest stable version tag and my patch before installing the
-software.
-
-Commit log before upgrading:
-
-```
-dt236  My patch.
-3fkdf  Version 6.5.
-```
-
-Commit log after pulling:
-
-```
-w467d  My patch.
-gh25g  A commit.
-g525g  Another commit.
-3fkdf  Version 6.6.
-vd425  Old commit.
-q12vu  Another old commit.
-3fkdf  Version 6.5.
-```
-
-Commit log after the interactive rebase:
-
-```
-h57jh  My patch.
-3fkdf  Version 6.6.
-vd425  Old commit.
-q12vu  Another old commit.
-3fkdf  Version 6.5.
-```
-
-And finally, commit and push all the changes to my own git repository.
-