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 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.