50 karma · joined April 21, 2026
Backend/systems engineer, 18+ years.
Recent: g6k-rs — Rust lattice reduction (LLL/BKZ/sieving, CPU/Metal GPU); Orch8 — Rust durable workflow/AI engine, 2,400+ instances/sec; crypto exchange — matching engine, 4,000+ orders/sec, sub-ms latency.
Looking for: Backend/Systems/Tech Lead — Rust or Node.js, Web3/crypto, AI infrastructure. Full-time or B2B.
CV: https://www.ovasylenko.com | hello@ovasylenko.com
One tiny correction
random.randrange(100) gives 300 possible commitments(3 colors for hundred nonces) After seeing a couple of revealed edges, the verifier can figure out the palette and brute-force all 300 combinations, effectively opening every commitment.
It can be mitigated if we use 128 bits of randomness, e.g. secrets.token_bytes(16).
Also I would use sha256 instead of hash. Python hash is not considered secure as it does not have proper collision resistance.
It includes LLL, BKZ, CVP, enumeration, several sieves, arbitrary-precision arithmetic, and experimental Metal/CUDA paths.
Will be happy for any feedback or review shared.
Please contact me at hello@ovasylenko.com / ovasylenko.com for any reason
Résumé/CV: https://www.ovasylenko.com Email: hello@ovasylenko.com
Backend & systems engineer, 18+ years.
Three recent builds: g6k-rs lattice reduction engine supports CPU/Metal/GPU with all contemporary algorithms: LLL, BKZ, Sieving, DeepLLL, Seysen etc with arbitary precision
Rust — Solo-built Orch8 (orch8.io), a durable workflow orchestration engine. 2,400+ instances/sec, <3ms latency. 7 crates, 3 SDKs (Node/Python/Go), 200+ integrations, built-in LLM tool calling and ReAct agent loops. Node.js/NestJS — Matching engine for a crypto exchange processing 4,000+ orders/sec with sub-millisecond latency. Liquidity bots, candle engine, real-time WebSocket trading.
Looking for: Backend/Fullstack developer/Tech lead (Node.js or Rust), Web3/protocol engineering, or AI infrastructure roles. I care about product ownership and shipping - not process theater.
Open to b2b contracts
Node.js/NestJS — Matching engine for a crypto exchange processing 4,000+ orders/sec with sub-millisecond latency. Liquidity bots, candle engine, real-time WebSocket trading.
Also: zk-SNARK wallet engine at Panther Protocol (cross-chain, UTXO model), micro-frontend migration at PropertyGuru (4 product teams). Led 15 engineers across 3 time zones.
Looking for: Senior/Staff Rust systems, backend architecture (Node.js or Rust), Web3/protocol engineering, or AI infrastructure roles. I care about product ownership and shipping - not process theater.
I have a weird feeling. Query body is encrypted by https. So CDN will not be able to cache results. In order to make it work right - whole topology of the internet should be redone. Caching on the backend server will not give any real gains for large scale apps.
Backend & systems engineer, 18+ years. Two recent builds: Rust — Solo-built Orch8 (orch8.io), a durable workflow orchestration engine. 2,400+ instances/sec, <3ms latency. 7 crates, 3 SDKs (Node/Python/Go), 200+ integrations, built-in LLM tool calling and ReAct agent loops.
Node.js/NestJS — Matching engine for a crypto exchange processing 4,000+ orders/sec with sub-millisecond latency. Liquidity bots, candle engine, real-time WebSocket trading.
Also: zk-SNARK wallet engine at Panther Protocol (cross-chain, UTXO model), micro-frontend migration at PropertyGuru (4 product teams). Led 15 engineers across 3 time zones.
Looking for: Senior/Staff Rust systems, backend architecture (Node.js or Rust), Web3/protocol engineering, or AI infrastructure roles. I care about product ownership and shipping - not process theater.
Also, sorry for the noob question, is not such server generate enormous amount of heat? You did not use any special cooling system?
TBH, it is my first post here and I am nervous a lot, as I put a lot of effort into this product. I have been building http://orch8.io for past 2 months. The story started when I used Temporal for long-running workflows, month after month/many months/years, and ended up in a situation where I needed to write lots of fixes around Temporal. Temporal is a great tool, covering most of the use cases, but for long-running execution, solution around it is starting to be very painful and too complex. Especially if the workflow can be updated 2-3 times during execution.
So I decided to go with Rust, as it is fast, small, and can have only 1 binary. Atm it supports only two dbs. SQLite for local development and PostgreSQL for scaling.
Workflows are defined as JSON blocks(sequences), and the engine persists state so work can resume after crashes or restarts.
Orch8 includes many workflow/application semantics out of the box. Instead of modeling everything as code-level activities, sequences use higher-level blocks directly:
- Semantics: Parallel, Race, TryCatch, Loop, ForEach, Router, SubSequence, and CancellationScope blocks
- A/B testing blocks for deterministic variant selection
- Built-in LLM calls across major providers(Also, LLM can inject additional steps into the current execution automatically, if you design the sequence that way)
- Human review(when smn need to approve before the decision. It is very helpful for early sequence development, where there might be bugs and you need to verify that you are not doing something wrong on critical blocks. One use case, I have connected it to a Telegram bot with the Polymarket test. I am getting information, should we go or not go with bet on analysis done with LLM and opportunities found )
- I decided to integrate ActivePieces out of the box. It allows to have 200+ connectors to different tools immediately and takes the burden of diversity of integrations off my shoulders
- Any non-standard behavior is done via external workers in any language via REST polling. Also, I shipped 3 SDKs: Node/Python/Go
- JSON-defined workflows that can be generated, versioned, and shipped without compiling worker code
- Overall I wrote 2000+ tests 1300 unit, 700 integration tests, and increasing coverage every week
Other pieces included today:
- Durable execution with retries, snapshots, and dead-letter handling
- Scheduling with relative delays, business-day rules, timezones, send windows, and cron triggers. F.e. never send sales emails on weekends; Or use jitter window of 4 hours to send 1000 emails.
- Rate-limit pools with rotation, daily caps, warmup ramps, and defer-on-limit behavior
- Added Prometheus metrics, structured logs, and audit logs(I did not test it well in prod, yet, might be some glitches)
- I have created a polymarket worker for anyone who wants to integrate it. It covers all API and is located in org repo.
Will be honest:
- This is not battle-tested at Temporal scale
- No visual workflow builder yet; sequences are JSON for now. Plan in the nearest future. But it is nice-to-have, I do not see crucial value in it. Thought, I have a vision how to make it different and friendlier than usual(thanks for 6 years of d3 development in early career)
- Still early, so I would not pretend every production edge case has been found. But I really appreciate contribution or suggestions.
License is BUSL-1.1. You can use it in production unless you are offering Orch8 itself as a competing hosted/embedded service. Each release converts to Apache 2.0 after 4 years.
Links:
- GitHub: https://github.com/orch8-io/engine
- Docs: https://orch8.io/docs
- Quick start: `docker run -d -p 8080:8080 ghcr.io/orch8-io/engine:latest`
I would like to hear from people who have used Temporal, Airflow, Prefect, Dagster, or homegrown workflow systems. What are your pain points now?
Thank you, guys.
With respect, Oleksii.
Location: Rio de Janero, BR -3 GMT
Remote: Yes
Willing to relocate: No
Technologies: Rust, Nodejs, Typescript, React, Postgres, optimizations and mission critical systems, systems toolkits, exchanges, security audits
Résumé/CV: www.ovasylenko.com
Email: hello@ovasylenko.com
Others: Get things done attitudeIf I were you I would also develop interactive opening tree as an embeddable widget for chess blogs, coaches, and content creators. Chess.com is static one.
Also if you can get api/history of user plays - you can help them with analyze to get better openers and become better players.