Jayng9663

Build and Run on kernel using QEMU

Wed, 08 Apr 2026 16:10:31 -0700

Just for personal note, haven’t test on others.

Kernel Config

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make defconfig CC=clang

if want to include other module which is not enable be default in defconfig. run for e.g.

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./scripts/config --module CONFIG_MAC80211_HWSIM
./scripts/config --module CONFIG_IWLWIFI=y
./scripts/config --module CONFIG_IWLWIFI_LEDS=y
./scripts/config --module CONFIG_IWLDVM=m
./scripts/config --module CONFIG_IWLMVM=m

build-kernel.sh

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#!/bin/bash
set -e
 
make CC=clang -j$(nproc)
python3 scripts/clang-tools/gen_compile_commands.py
 
echo "Done — bzImage ready at arch/x86/boot/bzImage"

For subsequent small changes just run make CC=clang -j$(nproc) directly. Make only recompiles changed files, so a single .c change takes a few seconds.

Raw Kernel + Busybox Initramfs

QEMU loads the kernel and a cpio archive, the kernel unpacks it into a tmpfs, runs /init, and drops you into a busybox shell.

build-initramfs.sh

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#!/bin/bash
set -e
 
KBUILD=$(pwd)
 
rm -rf initramfs
mkdir -p initramfs/{bin,sbin,etc,proc,sys,dev,lib/modules}
 
cp /usr/bin/busybox initramfs/bin/
cd initramfs/bin
./busybox --install .
cd "$KBUILD"
 
cat > initramfs/init << 'EOF'
#!/bin/sh
mount -t proc none /proc
mount -t sysfs none /sys
mount -t devtmpfs none /dev 2>/dev/null || mdev -s
 
echo "Kernel $(uname -r) booted!"
exec /bin/sh
EOF
 
chmod +x initramfs/init
 
cd initramfs
find . | cpio -o -H newc | gzip > ../initramfs.cpio.gz
cd ..
 
echo "Done — initramfs.cpio.gz ready"

boot.sh

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#!/bin/bash
set -e
 
KBUILD=$(pwd)
 
qemu-system-x86_64 \
 -kernel "$KBUILD/arch/x86/boot/bzImage" \
 -initrd "$KBUILD/initramfs.cpio.gz" \
 -append "console=ttyS0,115200 earlyprintk=serial,ttyS0,115200 rdinit=/init nokaslr" \
 -nographic \
 -serial mon:stdio \
 -device e1000,netdev=net0 \
 -netdev user,id=net0,hostfwd=tcp::2222-:22 \
 -m 512M \
 -no-reboot

Rebuild

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bash build-kernel.sh
bash build-initramfs.sh
bash boot.sh

Exit QEMU with Ctrl-A X or run shutdown.

Full Arch Linux Rootfs

When you need pacman, ssh, or any real tooling, install Arch onto a qcow2 image and boot your custom kernel directly into it.

Create the Disk

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qemu-img create -f qcow2 rootfs.qcow2 10G

Install Arch from ISO

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qemu-system-x86_64 \
 -cdrom archlinux-x86_64.iso \
 -boot d \
 -drive file=rootfs.qcow2,format=qcow2 \
 -device e1000,netdev=net0 \
 -netdev user,id=net0,hostfwd=tcp::2222-:22 \
 -m 2G \
 -enable-kvm \
 -no-reboot \
 -vnc :0

Connect with vncviewer localhost:5900. Inside the installer:

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fdisk /dev/sda << 'EOF'
g
n
1
 
 
w
EOF
 
mkfs.ext4 /dev/sda1
mount /dev/sda1 /mnt
 
# base only, no need linux package
pacstrap /mnt base
genfstab -U /mnt >> /mnt/etc/fstab
arch-chroot /mnt
 
passwd root
 
# Network (optional)
cat > /etc/systemd/network/20-wired.network << 'NET'
[Match]
Name=ens3
 
[Network]
DHCP=yes
NET
 
systemctl enable systemd-networkd systemd-resolved
 
exit
umount -R /mnt
poweroff

boot.sh

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#!/bin/bash
set -e
 
KBUILD=$(pwd)
 
qemu-system-x86_64 \
 -kernel "$KBUILD/arch/x86/boot/bzImage" \
 -drive file="$KBUILD/rootfs.qcow2",format=qcow2 \
 -append "console=ttyS0,115200 earlyprintk=serial,ttyS0,115200 root=/dev/sda1 rw nokaslr" \
 -nographic \
 -serial mon:stdio \
 -device e1000,netdev=net0 \
 -netdev user,id=net0,hostfwd=tcp::2222-:22 \
 -m 2G \
 -enable-kvm \
 -no-reboot

SSH in with:

📝 Note

Need to install and start openssh, and set PermitRootLogin = yes in /etc/ssh/ssh_config.

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ssh -p 2222 root@127.0.0.1

Rebuild

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bash build-kernel.sh
bash build-initramfs.sh
bash boot.sh

Exit QEMU with Ctrl-A X or run shutdown.

VN Presence

Mon, 30 Mar 2026 01:27:09 -0700

Discord Rich Presence daemon for Visual Novels on Linux. Detects games launched via Lutris or Steam, looks them up on VNDB, and shows the title, cover art, and total playtime in your Discord status.

Voice channel

User activity

Features

Detects games from Lutris (exact name from wrapper) and Steam (AppID → ACF → store name)
Fuzzy title matching against VNDB using trigram similarity + full-width character normalisation
Fallback: searches the release endpoint and follows the relation back to the parent VN
Suppresses explicit cover images (sexual ≥ 1.80 or violence ≥ 1.80) — title still shows
Playtime from Lutris DB (pga.db) or Steam VDF (localconfig.vdf) — no API key needed
Discord elapsed timer reflects total hours played, not just this session
Editable cache.csv for aliases, hard-links, and SKIP entries — reloaded live while running
ignore.txt with exact-match for short entries (< 4 chars) to prevent false positives like sh

How it works

Main loop

Every 5 seconds the daemon runs detection, debounces the result, checks the cache, queries VNDB if needed, and updates Discord.

flowchart LR
 A[Detection\nLutris or Steam] --> B[Debounce\nstable 2 polls]
 B --> C{Cache\nlookup}
 C -- hit + fresh --> E[Discord RPC]
 C -- hit + expired --> D[VNDB search]
 C -- miss --> D
 D --> E

Detection

flowchart TD
 P[Scan /proc every 5s]
 P --> L{lutris-wrapper\nin cmdline?}
 L -- yes --> LN[Game name from\nwrapper args]
 L -- no --> S{SteamAppId\nin environ?}
 S -- yes --> SA[Read appmanifest_ID.acf\nfrom all library paths]
 SA --> SN[Steam store name]
 S -- no --> NONE[Nothing detected]
 LN --> ST[Read starttime\nfrom /proc/pid/stat field 22]
 SN --> ST
 ST --> SORT[Sort candidates\nby starttime ascending]

Lutris passes the game name explicitly as command-line arguments after lutris-wrapper, so the name is always exact. Steam injects SteamAppId as an environment variable into every game process — the daemon reads it from /proc/<pid>/environ, then finds the matching .acf file across all Steam library paths (including custom drives read from libraryfolders.vdf).

After all candidates are collected, the daemon reads field 22 (starttime) from each process’s /proc/<pid>/stat. Candidates are then sorted ascending by starttime, so the process that launched first is always tried first during VNDB resolution. This makes multi-candidate priority deterministic and reproducible across polls.

📝 Note

See the proc/[PID]/stat field reference for a full breakdown of all stat fields.

💡 Tip

Run with --verbose to see candidates list in the debug output:

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[DEBUG] src/main.cpp:73 4 game candidate(s) found:
 [DEBUG] src/main.cpp:75 [lutris] pid=2037324 name="終ノ空 remake" starttime(clock ticks)=4906595
 [DEBUG] src/main.cpp:75 [lutris] pid=2086738 name="X-Plane 12" starttime(clock ticks)=4906701
 [DEBUG] src/main.cpp:75 [steam-appid] pid=2037822 name="心象天儀本線 ~Per aspera ad astra~ Demo" starttime(clock ticks)=4906857
 [DEBUG] src/main.cpp:75 [lutris] pid=2038526 name="サクラノ詩－櫻の森の上を舞う－" starttime(clock ticks)=4907260

VNDB resolution

flowchart TD
 Q[Search query] --> VN[POST /kana/vn]
 VN --> SIM{Trigram similarity\n≥ 0.35 OR substring match?}
 SIM -- yes --> MATCH[VnInfo returned]
 SIM -- no --> REL[POST /kana/release]
 REL --> FOUND{Release found?}
 FOUND -- yes --> ID[Fetch parent VN\nby exact ID]
 ID --> MATCH
 FOUND -- no --> NOMATCH[No match\nclear presence]

Before the similarity check, full-width ASCII (！２→!2, （→() is normalised to half-width so Japanese game names from Lutris match VNDB’s stored titles. There is also a substring boost — if the query appears inside the returned title, the score is raised to at least 0.6, handling cases where the detected name is a short prefix of a long VNDB title.

Cache TTL

VNDB results are stored persistently in cache.csv. On each cache hit the daemon compares the entry’s cached_at timestamp against VNDB_CACHE_TTL. If the entry is older than the TTL, it is treated as expired and a fresh VNDB query is issued, updating the stored data and timestamp.

flowchart TD
 HIT[Cache hit] --> AGE{age > VNDB_CACHE_TTL?}
 AGE -- no --> USE[Use cached VnInfo]
 AGE -- yes --> REQUERY[Re-query VNDB\nupdate cache.csv]
 REQUERY --> USE

This means ratings, cover images, and release dates in the cache are automatically refreshed over time without any manual intervention. The log line when a re-query fires looks like:

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[INFO] Cache expired for "..." age=1442min/1440min — re-querying VNDB

Playtime → Discord elapsed timer

flowchart TD
 SRC{Source?}
 SRC -- lutris --> LDB[Lutris DB\npga.db · hours]
 SRC -- steam-appid --> VDF[Steam VDF\nlocalconfig.vdf · minutes]
 LDB --> PT[playtime in seconds]
 VDF --> PT
 PT --> TS[start_ts = now − playtime]
 TS --> DISC[Discord: elapsed timer\ncounts up from start_ts]

Cache file (`cache.csv` / `cache.db`)

Located at ~/.config/vn-discord-rpc/cache.csv (default) or cache.db when CACHE_USE_DB = true. Reloaded automatically whenever the file changes on disk.

Column	Purpose
`key`	Detected Visual Novels name (the search term)
`alias`	Redirect this key to a different search term
`vndb_id`	`v562`, `v67`, `SKIP`, or empty
`title`	Romanised VNDB title (auto-filled)
`alt_title`	Original script title, e.g. Japanese (auto-filled)
`image_url`	Cover image URL (auto-filled, blank if explicit(sexual or violence))
`image_sexual`	VNDB sexual rating 0–2 (auto-filled)
`image_violence`	VNDB violence rating 0–2 (auto-filled)
`rating`	VNDB community rating 0–100 (auto-filled)
`released`	Release date (auto-filled)
`cached_at`	Unix timestamp of last write (auto-filled)

Examples:

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# Alias — fix wrong or garbled detection
Nice boat!,School Days,,,,,,,,

# Skip — suppress presence for this title
妹ぱらだいす！２,,SKIP,,,,,,,

# Hard-link — bypass VNDB query, point directly to an entry
My VN Title,,v67,,,,,,,

Ignore list (`ignore.txt`)

Located at ~/.config/vn-discord-rpc/ignore.txt. One entry per line, # for comments. Reloaded automatically while running.

Matching rules:

Entry < 4 characters: exact match (case-insensitive) — (ie. prevents sh matching Higurashi)
Entry ≥ 4 characters: case-insensitive substring match

The default file includes common false-positives: Steam runtimes, Proton, Wine helpers, and launchers.

⚠️ Warning

If a title has no VNDB match and is not in the ignore list, the daemon will not add it to ignore automatically. It will retry the VNDB query on every detection. Add a SKIP entry in cache.csv or an entry in ignore.txt to suppress it permanently.

Configuration (`src/config.hpp`)

🚨 Caution

Be caution on changing IMAGE_SEXUAL and IMAGE_VIOLENCE thresholds in src/config.hpp. Those thresholds are set to 1.80 (slightly below VNDB’s Explicit level of 2.00) because VNDB image ratings are user-reported and may be underrated by a small margin — the 0.20 buffer ensures borderline explicit covers are still suppressed. Raising the threshold above 2.00 would cause explicit (pornographic) cover art to appear in your Discord status, visible to everyone on your friends list. Displaying explicit content in Discord Rich Presence may violates Discord’s Terms of Service and may result in a permanent account ban.

Constant	Default	Description
`DISCORD_APP_ID`	`1482345564698841189`	Discord application ID
`DISCORD_ACTIVITY_TYPE`	`0`	Activity type: 0=Game, 1=Streaming, 2=Listening, 3=Watching
`IMAGE_SEXUAL`	`1.80`	Maximum sexual rating before cover is suppressed
`IMAGE_VIOLENCE`	`1.80`	Maximum violence rating before cover is suppressed
`IMAGE_VOTECOUNT`	`5`	Minimum vote count before ratings are trusted
`VNDB_MIN_SIMILARITY`	`0.35`	Minimum trigram score to accept a VNDB match
`POLL_INTERVAL`	`5s`	How often to scan `/proc` for running processes
`VNDB_CACHE_TTL`	`24h`	How long a cache entry is valid before re-querying VNDB
`STABLE_TITLE_POLLS`	`2`	Polls a candidate must be stable before acting
`VNDB_MAX_RESULTS`	`1`	Maximum results per VNDB query (index 0 is used)
`CACHE_USE_DB`	`false`	Use SQLite (`cache.db`) instead of CSV (experimental)
`RPC_STATE_READING`	`"Reading"`	Discord state string while a VN is active
`RPC_STATE_IDLE`	`"Idle"`	Discord state string while idle
`RPC_DEFAULT_DETAILS`	`"Playing a Visual Novel"`	Details line when no VNDB match is found
`RPC_SMALL_IMG_KEY`	`"vndb_logo"`	Discord asset key for the small VNDB logo image
`RPC_SMALL_IMG_TEXT`	`"VNDB"`	Tooltip text for the small image

Architecture

The project is composed of nine focused, single-responsibility modules:

Module	Source Files	Responsibility
Entry point	`main.cpp`	Main loop, debounce state machine, candidate resolution pipeline
Process scanner	`process_scanner.cpp/.hpp`	Iterates `/proc`, detects Lutris and Steam game processes, reads `starttime`
Steam detector	`steam_detector.cpp/.hpp`	Reads `SteamAppId` env vars, parses ACF manifests and VDF playtime files
VNDB client	`vndb_client.cpp/.hpp`	HTTP POST to VNDB Kana API, trigram matching, release endpoint fallback
VN cache	`vn_cache.cpp/.hpp`	Persistent CSV/SQLite cache with alias, SKIP, TTL, and live-reload logic
Ignore list	`ignore_list.cpp/.hpp`	Live-reloadable process-name suppression list with exact/substring rules
RPC manager	`rpc_manager.cpp/.hpp`	Discord IPC wrapper with rate limiting, deferred flush, and change detection
Config	`config.hpp`	All compile-time constants in one place
Logger	`logger.hpp`	Thread-safe ANSI-coloured logger singleton with `LOG_DEBUG/INFO/WARN/ERR` macros
Lutris DB	`lutris_db.cpp/.hpp`	Reads and formats playtime from Lutris’s SQLite `pga.db`

Key Design Decisions

Deterministic multi-candidate priority — when multiple games are running, candidates are sorted by /proc/<pid>/stat field 22 (starttime, clock ticks since boot). The process that launched earliest is always tried first, making priority stable and reproducible across polls without any user configuration.

Discord rate-limit compliance — Discord silently drops SET_ACTIVITY calls faster than ~15 seconds apart. RpcManager tracks the wall-clock time of the last successful push and defers any call that falls within a 16-second window. Deferred updates are flushed on the next runCallbacks() tick, ensuring no update is ever lost.

No presence flicker on stable sessions — the early-out in the main loop checks whether the currently displayed VN is still in the candidate set before doing any cache or VNDB work. If it is still running, the loop sleeps immediately, so Discord is never unnecessarily cleared and re-set.

Cache-first, ignore-list-second — VNDB HTTP queries are only issued on a true cache miss or TTL expiry. Candidates that fail VNDB resolution are added to the ignore list so subsequent polls skip them instantly, letting the next candidate be tried without any network round trip.

Live file reloading without restart — both cache.csv and ignore.txt are checked for mtime changes on every poll using std::filesystem::last_write_time. Edits made while the daemon is running take effect within one poll cycle with no signals or process restart needed.

Explicit content safety — image ratings are only trusted when backed by at least IMAGE_VOTECOUNT votes. Cover URLs are stripped from cache entries for explicit results so they can never accidentally appear after a cache reload even if thresholds are later changed.

Building

📌 Important
Initialise submodules before building — the two header-only dependencies are not downloaded automatically.
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git submodule update --init --recursive

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cmake -B build -DCMAKE_BUILD_TYPE=Release
cmake --build build

Dependencies

Library	Purpose
discord-presence	Discord Rich Presence (modern C++ rewrite)
nlohmann/json	JSON parsing
libcurl	HTTP requests to VNDB API
libsqlite3	Read Lutris playtime database

Usage

💡 Tip

Run with --verbose if a title is not being detected or matched — the debug output shows exactly which process was found, what VNDB returned, and the similarity score.

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./vn-discord-rpc # normal
./vn-discord-rpc --verbose # debug logging
./vn-discord-rpc --help

Launch a game through Lutris or Steam, and the daemon will detect it automatically. Press Ctrl+C to quit cleanly.

File locations

File	Path
Cache (CSV)	`~/.config/vn-discord-rpc/cache.csv`
Cache (SQLite, experimental)	`~/.config/vn-discord-rpc/cache.db`
Ignore list	`~/.config/vn-discord-rpc/ignore.txt`
Lutris DB	`~/.local/share/lutris/pga.db`
Steam VDF	`~/.local/share/Steam/userdata/<id>/config/localconfig.vdf`

/proc/[PID]/stat Field Reference

Sun, 29 Mar 2026 23:08:22 -0700

The /proc/[PID]/stat file exposes process status information. Each field is listed below in order of appearance.

Fields

ID	Field	Description
1	`pid`	Process ID
2	`tcomm`	Filename of the executable
3	`state`	Process state: `R` running, `S` sleeping, `D` uninterruptible sleep, `Z` zombie, `T` traced or stopped
4	`ppid`	Process ID of the parent process
5	`pgrp`	Process group ID
6	`sid`	Session ID
7	`tty_nr`	TTY the process uses
8	`tty_pgrp`	Process group ID of the TTY
9	`flags`	Task flags
10	`min_flt`	Number of minor faults
11	`cmin_flt`	Number of minor faults including children
12	`maj_flt`	Number of major faults
13	`cmaj_flt`	Number of major faults including children
14	`utime`	User mode jiffies
15	`stime`	Kernel mode jiffies
16	`cutime`	User mode jiffies including children
17	`cstime`	Kernel mode jiffies including children
18	`priority`	Priority level
19	`nice`	Nice level
20	`num_threads`	Number of threads
21	`it_real_value`	(Obsolete, always 0)
22	`start_time`	Time the process started after system boot
23	`vsize`	Virtual memory size
24	`rss`	Resident set memory size
25	`rsslim`	Current limit in bytes on the RSS
26	`start_code`	Address above which program text can run
27	`end_code`	Address below which program text can run
28	`start_stack`	Address of the start of the main process stack
29	`esp`	Current value of ESP
30	`eip`	Current value of EIP
31	`pending`	Bitmap of pending signals
32	`blocked`	Bitmap of blocked signals
33	`sigign`	Bitmap of ignored signals
34	`sigcatch`	Bitmap of caught signals
35	(placeholder)	(Was wchan address — use `/proc/[PID]/wchan` instead)
36	(placeholder)	(Reserved)
37	(placeholder)	(Reserved)
38	`exit_signal`	Signal sent to the parent thread on exit
39	`task_cpu`	CPU the task is scheduled on
40	`rt_priority`	Realtime priority
41	`policy`	Scheduling policy (see `man sched_setscheduler`)
42	`blkio_ticks`	Time spent waiting for block I/O
43	`gtime`	Guest time of the task in jiffies
44	`cgtime`	Guest time of child tasks in jiffies
45	`start_data`	Address above which program data+BSS is placed
46	`end_data`	Address below which program data+BSS is placed
47	`start_brk`	Address above which the heap can be expanded with `brk()`
48	`arg_start`	Address above which the command line is placed
49	`arg_end`	Address below which the command line is placed
50	`env_start`	Address above which the environment is placed
51	`env_end`	Address below which the environment is placed
52	`exit_code`	Thread exit code as reported by `waitpid`

Example

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871869 (VN-Presence) S 12198 871869 12198 34830 871869 4194560 1205 0 173 0 46734 8492 0 0 20 0 2 0 10523393 176685056 2837 18446744073709551615 94266814361600 94266814993397 140734575381584 0 0 0 0 0 16386 0 0 0 17 16 0 0 0 0 0 94266815325280 94266815330208 94267110821888 140734575389833 140734575389847 140734575389847 140734575394794 0

Parsed field by field:

ID	Field	Value	Notes
1	`pid`	`871869`	Process ID
2	`tcomm`	`(VN-Presence)`	Executable name
3	`state`	`S`	Sleeping (interruptible)
4	`ppid`	`12198`	Parent PID
5	`pgrp`	`871869`	Process group ID
6	`sid`	`12198`	Session ID
7	`tty_nr`	`34830`	TTY device number
8	`tty_pgrp`	`871869`	Foreground process group of TTY
9	`flags`	`4194560`	Task flags
10	`min_flt`	`1205`	Minor page faults
11	`cmin_flt`	`0`	Minor faults including children
12	`maj_flt`	`173`	Major page faults
13	`cmaj_flt`	`0`	Major faults including children
14	`utime`	`46734`	User-mode CPU time (jiffies) — ~467s at 100 Hz
15	`stime`	`8492`	Kernel-mode CPU time (jiffies) — ~84s at 100 Hz
16	`cutime`	`0`	Children user-mode jiffies
17	`cstime`	`0`	Children kernel-mode jiffies
18	`priority`	`20`	Kernel priority
19	`nice`	`0`	Nice value (0 = default)
20	`num_threads`	`2`	Thread count
21	`it_real_value`	`0`	Obsolete, always 0
22	`start_time`	`10523393`	Jiffies after boot when process started
23	`vsize`	`176685056`	Virtual memory size (168 MiB)
24	`rss`	`2837`	Resident set size (pages) — 2837 × 4 KiB ≈ 11 MiB
25	`rsslim`	`18446744073709551615`	RSS limit (0xFFFFFFFFFFFFFFFF = unlimited)
26	`start_code`	`94266814361600`	Start of executable text segment
27	`end_code`	`94266814993397`	End of executable text segment
28	`start_stack`	`140734575381584`	Stack start address
29	`esp`	`0`	Current stack pointer
30	`eip`	`0`	Current instruction pointer
31	`pending`	`0`	Pending signals bitmap
32	`blocked`	`0`	Blocked signals bitmap
33	`sigign`	`16386`	Ignored signals bitmap
34	`sigcatch`	`0`	Caught signals bitmap
35	(placeholder)	`0`	(Was wchan)
36	(placeholder)	`0`	(Reserved)
37	(placeholder)	`0`	(Reserved)
38	`exit_signal`	`17`	Signal sent to parent on exit (17 = SIGCHLD)
39	`task_cpu`	`16`	Last CPU the task ran on
40	`rt_priority`	`0`	Realtime priority (0 = not realtime)
41	`policy`	`0`	Scheduling policy (0 = SCHED_NORMAL)
42	`blkio_ticks`	`0`	Block I/O wait ticks
43	`gtime`	`0`	Guest time (jiffies)
44	`cgtime`	`0`	Children guest time (jiffies)
45	`start_data`	`94266815325280`	Start of data+BSS segment
46	`end_data`	`94266815330208`	End of data+BSS segment
47	`start_brk`	`94267110821888`	Start of heap
48	`arg_start`	`140734575389833`	Start of command-line args
49	`arg_end`	`140734575389847`	End of command-line args
50	`env_start`	`140734575389847`	Start of environment
51	`env_end`	`140734575394794`	End of environment
52	`exit_code`	`0`	Exit code

Notes

Fields are space-separated and appear in the order listed above.
Time values (utime, stime, etc.) are measured in jiffies (clock ticks). Divide by sysconf(_SC_CLK_TCK) to convert to seconds.

References

The /proc Filesystem linux kernel doc
Linux kernel source: fs/proc/array.c

心象天儀本線 ~Per Aspera Ad Astra~ Demo

Sun, 29 Mar 2026 21:23:52 -0700

Title: 心象天儀本線 ~per aspera ad astra~
Developer: Atelier Ueshima Erika
VNDB: https://vndb.org/v54933
Official Website: https://www.hoshiorigakuen.com/
Steam: https://store.steampowered.com/app/3664060/

Demo release for the doujin visual novel 心象天儀本線 ~Per Aspera Ad Astra~, demo dropped January 29, 2026, ahead of the full release later in 2026. It caught my attention when I looking up new game on Steam, because of it uniq doujin art style, 4:3 resolution and the incredibly ancient UI give it a classic visual novel feel, it reminds me of early 2000–2010 visual novels.

It’s a debut doujin visual novel from Atelier Ueshima Erika — a small indie studio out of Taiwan, as far as I can tell — and you play as 上島椿 (Ueshima Tsubaki) at the end of the demo, a mysterious girl reveals that it's actually Ueshima Tsubaki who has been talking to you — the player — all along in train , a transfer student arriving at the 星織學園 (Hoshiori Academy). The story is told through what the game calls “touching tickets”: fragmented vignettes that slowly build toward something larger. A Literature Club. A galactic train. Recurring dreams. It shouldn’t cohere, and yet it does.

What gets me is how intentional it all feels. The dreamlike art and surreal structure don’t come across as aesthetic choices slapped on top — they feel load-bearing, like the whole thing would collapse without them. And the soundtrack by composer 10lulu (60+ tracks planned for the full release, apparently), which I really like, its doing a lot of heavy lifting in the best possible way.

The full release is planned for later in 2026, promising 7–9 hours of playtime. If the demo is fit your type, this is one to keep on your wishlist. :L
I will make another post once it released and I when through. :L

Jayng9663

Build and Run on kernel using QEMU

Kernel Config

build-kernel.sh

Raw Kernel + Busybox Initramfs

build-initramfs.sh

boot.sh

Rebuild

Full Arch Linux Rootfs

Create the Disk

Install Arch from ISO

boot.sh

Rebuild

VN Presence

Voice channel

User activity

Features

How it works

Main loop

Detection

VNDB resolution

Cache TTL

Playtime → Discord elapsed timer

Cache file (cache.csv / cache.db)

Ignore list (ignore.txt)

Configuration (src/config.hpp)

Architecture

Key Design Decisions

Building

Dependencies

Usage

File locations

/proc/[PID]/stat Field Reference

Fields

Example

Notes

References

心象天儀本線 ~Per Aspera Ad Astra~ Demo

Cache file (`cache.csv` / `cache.db`)

Ignore list (`ignore.txt`)

Configuration (`src/config.hpp`)