Santhosh Raju

Experience

Senior Backend Engineer Jul 2022 — Present

HelloFresh SE Berlin, Germany

Owns the ~$4B/year Direct Procurement pipeline from HelloTech to Oracle Cloud Fusion, performing 2-way and 3-way match of POs and Receipts for payment processing.
Rearchitected the existing Kotlin microservices on the Workday ↔ Oracle Cloud Fusion integration to accept new business rules for indirect procurement, surfacing ~$400M/year of previously-invisible indirect spend to the business.
Cut Finance Tech infrastructure costs 73% through archiving cold data and retiring legacy services; architecting an LLM-backed support bot that auto-resolves 95%+ of incoming procurement support requests.
Architected and led the SKU Seasonality initiative — ingredient availability across suppliers throughout the seasonal year — cutting missing-SKU customer complaints from 52% → 18% and realising ~€2.4M in savings.
Helped the squad align with the company's Kafka restructure OKR — spanning 50+ repositories across 10 tribes, migrated with zero consumer downtime; consolidated the squad's owned topics from 180 → 20 (~€9K/month infra saved).
Built the nutrition + allergen aggregation pipeline for the Recipe Developer tools — surfaces correct legal-compliance data on the HelloFresh website across all markets for the ~950M+ meals/year HelloFresh delivers; drove a 25% YoY reduction in food-safety errors.

Backend Engineer May 2021 — Jun 2022

HelloFresh SE Berlin, Germany

Deprecated REMPS — the Mendix-based Recipe / Menu / SKU planning platform — across five European markets via last-mile Golang + PostgreSQL integrations with the Recipe / Menu planning tools; ~€480K/year per market in managed-hosted licensing eliminated (~€2.4M/year total).

Lead Backend Engineer Sep 2019 — Jul 2020

Sepia OS (SEPIAOPENSOURCE S.A.) Quito, Ecuador

Built Erol — a salary-advance fintech now serving 70+ companies / 8,000+ employees with ~$4M+ in advances processed across 20K+ requests — in Django + GraphQL on PostgreSQL; JWT auth with OTP second-factor via Infobip SMS.
Integrated with traditional banking APIs to generate and process bulk cash management files for automated fund disbursements to multiple institutions.
Set up the CI/CD pipeline on CircleCI and helped maintain the AWS EC2 deployment via Docker Swarm, provisioned with Ansible and Terraform; maintained 100% backend test coverage.

Senior Software Engineer Apr 2019 — Jul 2019

Centro de Autonomía Digital Quito, Ecuador

Implemented in-band password change (XEP-0077) for coyim (FreeBSD ports · pkgsrc) — an OTRv4-compliant XMPP messenger.
Researched and prototyped trusted Tor entry-guard selection for Tails OS.
Ported and maintained the OTRv4 library suite — libotr-ng, pidgin-otrng, libgoldilocks — for NetBSD (pkgsrc) and FreeBSD (ports), fixing critical bugs upstream was not yet ready to accept.

Founding Engineer / Tech Lead Jan 2018 — Sep 2018

Backyard Innovations Pte. Ltd. (BYI Systems) Bengaluru / Chiba, Japan / Singapore

Wrote TLA+ formal verification proofs for a voucher trading system based on RFC 3506; consulted with Masayuki Terada (NTT, Chiba) — co-author of the optimistic fair exchange protocol that informed the system design.
Implemented two-phase and three-phase commit consensus protocols for fail-safe voucher trading in Erlang.
Set up and maintained company infrastructure on FreeBSD with jails.

Earlier — Software Engineer / Consultant: The NetBSD Foundation · DRUP1 Consulting · KEENFX · Zyxware Technologies · Cognizant Technology Solutions (Dun & Bradstreet Swiss, Factiva — Dow Jones)

Annot 2026 — Present

Human-in-the-loop annotation tool for AI workflows (Rust + Svelte + Tauri) Linux/NixOS port maintainer

Contributed the Linux/NixOS port: Nix flake packaging for Linux + macOS, Wayland/WebKit2GTK rendering fixes, and borderless window with custom chrome and resize handles; packaged in the numtide/llm-agents.nix flake registry.

NetBSD 2016 — Present

A free, fast, secure, and highly portable Unix-like Open Source operating system Core committer, pkgsrc developer

Author and maintainer of 15+ pkgsrc packages (wolfssl, btop, coyim, py-Glances, and more); ported htop, psutil, and gopsutil to NetBSD via sysctl(3)/kvm(3) APIs, replacing procfs and unlocking gotop and bottom.
Co-mentored GSoC 2020 for The NetBSD Foundation — "Enhance Syzkaller support for NetBSD" — raising NetBSD syscall coverage to 50.35%.

FreeBSD 2019 — Present

A powerful, open source operating system Ports committer

Author and maintainer of 15+ FreeBSD ports including babashka, opengist, wolfssl, din, fasttracker2, markless, headscale, and pdfrip; 35 Bugzilla bugs handled as port maintainer (83 total Bugzilla contributions).

SICvm 2005 — Present

A SIC based virtual machine Virtual machine emulator in C

Developed a virtual machine emulating the SIC architecture (assembler, macro processor, VM). BSD-licensed.

The Future of Login 2025

How Drupal Can Champion User Choice, Privacy, and Simplicity Conference talk

Presented at DrupalCon Vienna 2025 with co-presenters Unnikrishnan and Anish Anilkumar, in collaboration with Hello Coop (founder Dick Hardt).
Contributed to the hellocoop/php SDK (Playwright e2e tests + CI) and the hello_login Drupal module, integrating Hello's privacy-preserving identity system with Drupal's auth layer.

Portable hotplugging 2017

NetBSD's uvm_hotplug(9) API development Paper

Replaced uvm(9)'s static vm_physmem array with a dynamic rbtree(3)-backed segment store, enabling live memory hotplug API; TDD-driven via atf(7) unit tests run in userspace before any kernel code; authored the uvm_hotplug(9) man page.
Co-authored with Cherry G. Mathew; published at AsiaBSDCon 2017 (Paper) and presented at AsiaBSDCon 2017 and EuroBSDCon 2017.

decant 2016

If you can't decant, distill it Conference talk

Built a plugin-driven Android framework routing SMS broadcasts through JavaScript filter functions — plugins hot-swap from external storage at runtime; embedded Mozilla Rhino engine; demonstrated plugins for Amazon orders, Domino's delivery, and IRCTC rail reservations at JSFoo 2016.