Nikita Chernyi

Principal Backend Engineer · Go · Distributed Systems & Federated Protocols PDF

Porto (Matosinhos), Portugal · EU-remote · Valid Portuguese residence permit (EU work authorisation, no sponsorship required)

Contacts

cv@rakshazi.me · LinkedIn (opens in new tab) · github.com/etkecc (opens in new tab) · Matrix (opens in new tab) · etke.cc/blog (opens in new tab)

Summary

Backend engineer, thirteen years in production, nine of them in Go. I design, build, and run distributed systems end to end: protocol work, storage, payments, observability, and the infrastructure underneath. Most of what I put my name to is software I’ve personally shipped and kept running.

etke.cc began as a side project in 2021 and became a bootstrapped company in 2026, with Slavi Pantaleev as cofounder. We’re a team of five running managed Matrix hosting: Cloud Hosting on Hetzner and On-Premises on customer infrastructure, 1,000+ Matrix servers installed across six regions on three continents. I lead engineering and write most of the in-house Go: the automation platform that runs the fleet, and the subscription and invoicing stack on top of it (Stripe, PayPal, Vendus). I also built MRS / MatrixRooms.info, the federated room-search engine, and Ketesa, our Matrix admin panel. We co-maintain matrix-docker-ansible-deploy and the M.A.S.H. playbook, the automation everything else runs on.

Since 2024 I’ve also worked on Hellotickets’ billing and payments platform. Between the two I stay fluent in two very different operational models: an Ansible-managed Hetzner fleet at etke.cc, and a Kubernetes and GitOps cloud stack at Hellotickets.

My focus is hands-on senior engineering rather than management. I keep etke.cc small by design and stay in the code alongside direct IC work, because building is the work I want to be doing. I do my best work where the stack spans protocols, storage, payments, and infrastructure at once, where reliability and operability are first-class concerns, and where the engineering has to answer to the business.

Areas of expertise

Backend Engineering · Distributed Systems · Federated Protocols (Matrix) · Payments & Billing · Infrastructure as Code · Production Operations · AI / LLM Systems · Open-Source Software

Technical stack

Languages. Go (primary, 9+ years in production). TypeScript, Python, PHP, and Bash are occasional: comfortable reading and writing smaller pieces in them. Backend. Go (Echo, mautrix-go, Bleve) · PostgreSQL, SQLite, Valkey · BoltDB for embedded stores · ElasticSearch · gRPC. Infrastructure & operations. Ansible, Docker, Hetzner Cloud, AWS, Azure, GCP, Kubernetes, Helm, ArgoCD, Terraform, Traefik · Prometheus, VictoriaMetrics, Grafana · GitLab CI, GitHub Actions, Jenkins. Payments & billing. Stripe, PayPal, NetSuite, payment-orchestration platforms, Vendus. AI / LLM systems. Practical LLM application engineering: model-curated memory, retrieval (FTS5/BM25), context compaction and summarisation, tool-use orchestration, and prompt-injection defence. Operations support. Sentry, Postmark, Redmine, FreeScout. Protocols. Matrix federation, SMTP, gRPC.

Work Experience

2021 - Present · Principal Backend Engineer & Founder · etke.cc (opens in new tab)

Remote · Portugal

etke.cc is a managed Matrix hosting service. A customer gets a dedicated, federated Matrix homeserver with their chosen bridges, clients, bots, and moderation tooling, and we run the whole thing end to end as a distributed system across multiple regions. I started it as a side project in 2021; it became a bootstrapped company in 2026, with Slavi Pantaleev as cofounder. We’re five now: four engineers and an administrator covering invoicing and accounting. No outside funding. I lead engineering and write the majority of the in-house Go microservices.

2024 - Present · Go Developer, Billing · Hellotickets (opens in new tab)

Remote

Hellotickets is an international live-events ticket marketplace, operating on a company-wide four-day work week. I work on the billing and payments platform.

2021 - 2023 · Senior Software Engineer · Crunchyroll (opens in new tab)

Remote · Chișinău, Moldova

Backend work across content discovery, search, and the home page at Crunchyroll’s scale: millions of requests per minute. On a team of five, including the engineering manager.

Selected Work

Federated room search (MRS)

Matrix has no central directory of public rooms. That stayed abstract until my wife went looking for a community she cared about and couldn’t find it, because nothing indexed the whole federation. That was the gap, so I built the search engine that didn’t exist.

MRS (opens in new tab) is an open-source Go service (Echo, Bleve, BoltDB) that discovers Matrix homeservers, reads only what each one publishes over federation (GET /_matrix/federation/v1/publicRooms), and reindexes the public federation daily. The constraint that shaped every decision: it never joins a room, never reads a message, never touches user data or a private setting. It indexes only what a server chooses to advertise, and admins can opt out at any time.

It also doubles as a trusted Matrix notary key server, and implements MSC1929, MSC3266, MSC4121, MSC4265, and MSC4439. MatrixRooms.info (opens in new tab) is the reference instance etke.cc runs, and the whole thing exists because finding a community should not require knowing which server it lives on.

Ketesa, an admin panel for Matrix

Synapse, the main Matrix homeserver, shipped without a real admin UI. The one existing option, synapse-admin, hadn’t kept pace, and etke.cc customers needed to actually run their servers: manage users, rooms, and moderation without a shell. So in 2024 we forked it, meaning to do nothing more than hotfix the parts that broke.

The temporary fork did not stay temporary. Dozens of releases later it had been rebuilt end to end and became Ketesa (opens in new tab), an independent product: mobile-first, ten fully-translated languages, full Matrix Authentication Service integration, and drop-in auto-configuration through /.well-known/matrix/client. It ships through GHCR, Docker Hub, our Ansible playbook, Nixpkgs, YunoHost, and the AUR.

For etke.cc customers it doubles as the control plane: live server status, scheduled maintenance, in-panel billing, and in-app ticketing. It is the only fully-featured admin panel Synapse has, and it got there the dull way: we kept showing up while the alternative went quiet.

Fleet-wide secrets at rest

Every customer homeserver runs on secrets held in one Ansible inventory: admin and database passwords, Synapse keys, S3 credentials, DKIM private keys, Borg backup passphrases. None of it should ever exist as plaintext, in git, on disk, or in a support chat on the way in.

The encryption layer is built on crypter, a small AES-GCM primitive in our public go-kit (opens in new tab). Its ENCv1[...] format is self-describing and idempotent both ways: it seals plaintext, passes already-sealed values through unchanged, and runs safely over a config file that mixes the two. On top of it, field-level and whole-file encryption across the inventory. Secrets are sealed in memory when an order is created, so cleartext never reaches disk, and decrypted only at point of use by the services that need them.

The pipeline has no bulk-decrypt endpoint. Operators seal secrets through a CLI and an internal web tool that only encrypts; a decrypt path would put the inventory key behind a single login and turn one compromised session into the whole fleet’s secrets. A lost secret is re-issued rather than recovered.

Earlier Experience (2013 - 2021)

2017 - 2021 · Senior Backend Developer & DevOps · Titanium Software (Chișinău, Moldova). Lead engineer and DevOps across five client projects. Drove the company’s adoption of Infrastructure-as-Code and a DevOps operating model. Notable work: Tpoint (squash-court IoT and booking platform), 2CB (B2B voice-automation portal), an industrial IoT project on Azure and AWS (Kubernetes, Couchbase, ElasticSearch), SportsWith (events platform on PHP 7.1 / Slim), MathodiX, fone.do.

2014 - 2017 · Backend Developer & DevOps · OpsWay (Remote). Magento e-commerce work. Authored 10+ production extensions; Ansible-managed dockerised deployments; flagship Antoshka.ua.

2013 - 2014 · Support Engineer · Active Computers (Tiraspol, Moldova). Web support and in-house tooling.

Selected Open-Source Projects

The full catalogue lives at github.com/etkecc (opens in new tab).

References

“Nikita is a good backend developer and DevOps engineer who is not afraid to jump into learning about new protocols and technologies. His work on etke.cc (and not only) demonstrates that he is capable of taking a problem and building a solution which spans the whole stack — business requirements, frontend and backend development, production deployment, and customer support.”

Slavi Pantaleev, Cofounder, etke.cc · Maintainer, matrix-docker-ansible-deploy

“Strong and passionate backend engineer with lots of focus on improving the performance and healthy state of the services he is working on. At Crunchyroll his focus was on building stable, scalable, and performant backend services handling millions of requests per minute — optimising not only how they perform but also how costly they are. He likes to delve into Go’s architecture so the team uses the language to its full capability.”

Vlad Ledniov, Engineering Manager, Crunchyroll

Languages

llms.txt