Hey, I am Saroj Mahato

SE @ PhonePe Infra | Distributed Systems | Platform Reliability

Solutions Engineer at PhonePe managing API Gateways, Object Storage, and Observability pipelines. I write about NixOS, Linux, distributed systems, or whatever stuff I'm currently building and tinkering with.

Find me on GitHub and LinkedIn.

Posts

AMD s2idle Sleep & Insyde BIOS on NixOS
2026-09-13
AMD s2idle Thermal Runaway & Insyde BIOS Updating on NixOS

Technical post-mortem and resolution for thermal runaway during lid sleep on AMD Zen4 (Lenovo IdeaPad Slim 5 16AHP9 / Type 83DD) running NixOS.

Incident Root Cause Analysis

When closing the laptop lid, systemd-suspend-then-hibernate initiated s2idle (suspend-to-idle). Log inspection (journalctl -b -1) revealed an ACPI PEP DSM failure:
```
kernel: amd_pmc AMDI0009:00: Last suspend didn't reach deepest state
kernel: ACPI BIOS Error (bug): Could not resolve symbol [\_SB.PCI0.GP17.XHC3.RHUB], AE_NOT_FOUND
kernel: ACPI Error: Aborting method \_SB.PEP._DSM due to previous error (AE_NOT_FOUND)
```
After 15 minutes, systemd-sleep woke the CPU to initiate hibernation (systemd-sleep: Performing sleep operation 'hibernate'). The kernel logged PM: hibernation: hibernation entry and hung before writing the hibernation image to swap. The SoC remained powered with the display lid closed, resulting in severe thermal buildup.

Firmware Update Procedure (Non-Windows Environment)

Inspection of DMI sysfs confirmed:
- Installed Version: NGCN29WW (2024-10-08)
- Latest Available Version: NGCN34WW (2026-01-16)
Lenovo packages firmware updates as a 7-Zip self-extracting Win32 executable (ngcn34ww.exe), which embeds InsydeH2O H2OFFT-Wx64.exe and ILS4P.bin.

Flashing via WinPE Live USB
1. Download Assets:
  - Lenovo BIOS executable: ngcn34ww.exe
  - Windows PE image: Hiren’s BootCD PE (HBCD_PE_x64.iso)
```
wget https://download.lenovo.com/consumer/mobiles/ngcn34ww.exe
axel -a -n 8 https://www.hirensbootcd.org/files/HBCD_PE_x64.iso
```
2. Flash to Ventoy USB:
```
cp HBCD_PE_x64.iso ngcn34ww.exe /run/media/creator54/Ventoy/ && sync
```
3. Execution:
  - Boot into Ventoy (F12), launch Hiren’s BootCD PE.
  - Verify AC adapter connection.
  - Run ngcn34ww.exe. H2OFFT-Wx64.exe loads H2OFFT64.sys in WinPE memory, writes the UEFI capsule trigger to NVRAM, and reboots.
  - Motherboard executes native Insyde UEFI capsule flash (NGCN34WW).
NixOS Power Management Configuration Fix

To eliminate broken suspend-then-hibernate on AMD s2idle platforms, configure services.logind to enforce direct hibernate on lid closure:

In hosts/omnix/hibernation.nix:
```
services.logind = {
  settings.Login = {
    HandleLidSwitch = "hibernate";
    HandleLidSwitchDocked = "hibernate";
    HandleLidSwitchExternalPower = "hibernate";
  };
};
```
Post-Fix Verification
```
cat /sys/class/dmi/id/bios_version   # NGCN34WW
cat /sys/class/dmi/id/bios_date      # 01/16/2026
sensors                               # CPU 53.4°C / NVMe 45.9°C
timedatectl                           # System clock synchronized: yes
nix flake check --all-systems --no-build --impure # All checks passed
```

nix-systems github.com/devswork-in/nix-systems

2026-09-08

Nix-Systems (NixOS)

NixOS configurations for an AMD/Niri workstation, an ARM production server, VM validation, and preserved dormant machines.

Layout

.
├── lib/                    # Helper functions (mkSystemConfig, mkAppImage)
├── profiles/               # Reusable profiles (base, desktop, server)
├── modules/
│   ├── apps/               # Application modules
│   ├── core/               # Core system modules
│   ├── desktop-utils/      # Desktop utilities and configurations
│   ├── desktops/           # Desktop environment modules
│   ├── server/             # Server configurations
│   ├── services/           # Service modules
│   └── extras/             # Additional modules
├── scheduled-scripts/      # Scheduled scripts
├── hosts/                  # Machine-specific configs
├── flake.nix               # Main configuration
├── config.nix              # User settings
└── sync-config.nix         # Sync configuration

Quick Start

Boot NixOS ISO
Run setup script:

sudo sh -c 'curl -sSL https://raw.githubusercontent.com/devswork-in/nix-systems/main/setup.sh | bash -s /dev/nvme0n1 omnix'

Warning: Wipes /dev/nvme0n1, repartitions & installs omnix flake.

Systems

See CONTEXT.md for the active/dormant target matrix and hardware boundaries.

Commands

See Usage for full details and Setup for installation.

sudo nixos-rebuild switch --flake .#omnix --impure       # Local workstation
nix run github:serokell/deploy-rs -- .#phoenix-arm      # Production server only
nix-repo-sync-force                                     # Force sync
nix-repo-sync-logs                                      # View logs
nix-cleanup --dry-run                                   # Cleanup preview
nix-cleanup                                             # Full cleanup
nixos-rebuild build-vm --flake .#omnix --impure          # GUI VM
nixos-rebuild build-vm --flake .#phoenix-x86 --impure    # Fast headless VM

Deployment

Phoenix (ARM)

Free at least 8 GiB on Phoenix before deployment. The x86 Phoenix output is VM-only and is deliberately absent from deploy.nodes.

Remote Build (builds on target):

nixos-rebuild --flake .#phoenix-arm --target-host phoenix --build-host phoenix switch --no-reexec -S

Local Build (Builds locally & pushes):

nixos-rebuild --flake .#phoenix-arm --target-host phoenix switch --no-reexec

Docs

This post was auto-generated from the devswork-in/nix-systems README. Last updated: 2026-09-14.

awrit github.com/Creator54/awrit
2026-06-16
Awrit

Personal fork of chase/awrit. See upstream for full documentation.

Note: Force Push Ahead.

Features & Roadmap
- Built-in Google Sign-In support (GIS and direct sign-in)
- 2-finger horizontal swipe for back/forward history navigation
- Vim-style keyboard bindings for page navigation
- Site-wise context zoom control (Alt+- / Alt+= / Ctrl+0)
- Zen-inspired Omnibox with intelligent search suggestions
- Interactive site permissions overlay via omnibox (camera, mic, geolocation)
- Multi-window handling support
- Bidirectional system clipboard interoperability (OSC 52 + bracketed paste)
- Proper standard XDG storage paths for data and logs (~/.local/share/awrit)
- Find in page functionality (Alt+/)
- Zero-latency page swaps (“Flash Killer”)
- Website click-to-copy and double/triple-click text selection
- Custom error pages for network failures and crashes
- Link hover status indicators
- In-app DevTools toggling (F12 / Ctrl+Shift+I)
- Chrome DevTools Protocol (CDP) support (--remote-debugging-port=9222)
- Aggressive resource limits (30fps caps, disabled spellchecker)
- Tear-free synchronized terminal output (2026 mode)
- High-performance rendering (BGRA->RGBA dirty rects, SIMD pass)
- Browser tabs support
- Settings page UI
- History navigation and cleanup
- Cookies and site data management
Install

Nix (Recommended):
```
# Run instantly without installing
nix run github:creator54/awrit -- https://github.com/creator54/awrit

# Or install to your user profile
nix profile install github:creator54/awrit

# For local development
git clone https://github.com/creator54/awrit.git && cd awrit
nix run .
```
Standard Linux:
```
git clone https://github.com/creator54/awrit.git
cd awrit
./setup.sh
./awrit
```
This post was auto-generated from the Creator54/awrit README. Last updated: 2026-08-20.
Why I moved to a minimal Astro setup
2026-06-15

Why I moved back to pure HTML/CSS

The modern web ships megabytes of JavaScript just to render static text.

I built this site to be fast and simple. No React hydration, no virtual DOM diffing, just a raw stream of HTML parsed instantly by the browser.

Using a few Google Fonts and minimal CSS is enough to achieve a clean look that loads in milliseconds.
Hello World — The Clean Slate
2026-06-14

Hello World — The Clean Slate

Welcome to the new blog.

I decided to start from scratch. This blog is built on Astro because it ships zero JavaScript by default.

Hey, I am Saroj Mahato

Posts

AMD s2idle Sleep & Insyde BIOS on NixOS

AMD s2idle Thermal Runaway & Insyde BIOS Updating on NixOS

Incident Root Cause Analysis

Firmware Update Procedure (Non-Windows Environment)

Flashing via WinPE Live USB

NixOS Power Management Configuration Fix

Post-Fix Verification

nix-systems github.com/devswork-in/nix-systems

Nix-Systems (NixOS)

Layout

Quick Start

Systems

Commands

Deployment

Phoenix (ARM)

Docs

awrit github.com/Creator54/awrit

Awrit

Features & Roadmap

Install

Why I moved to a minimal Astro setup

Why I moved back to pure HTML/CSS

Hello World — The Clean Slate

Hello World — The Clean Slate