Building high-performance foundations for Next-Gen AI. Expert in squeezing maximum TFLOPS out of consumer hardware and scaling LLM inference across distributed clusters.
Currently based in Curitiba, Brazil (GMT-3). Open to relocation worldwide.
Full C++/CUDA Runtime
- Transformer inference engine in pure C++/CUDA, no PyTorch execution path.
- 32.4k tok/s peak, achieving 87% of INT8 Tensor Core ceiling on RTX 2070.
- Custom Flash Attention, cuBLASLt INT8, CUDA Graphs, Megatron-style TP.
- Runs TinyStories 110M and TinyLlama 1.1B end-to-end.
PTX-Level GEMM Engineering
- Manual PTX instruction emission for Tensor Core GEMM.
- Beats cuBLAS at 2048×2048×2048; achieves 60-65% at 8192×8192×8192.
- Auto-tuning over WARPS / STAGE_K / ILP_DEPTH configuration space.
CUDA Kernel + End-to-End LLM Integration
- Bit-perfect INT4 weight-only quantization kernel using raw PTX assembly.
- Achieved 1.000 Cosine Similarity against FP16 baselines.
- End-to-end Qwen2-0.5B integration: -14.7% VRAM with coherent output.
- Documented SM75 structural limits (no cp.async, no INT4 MMA operands).
Compiler MVP with CUDA Codegen
- Full pipeline: IR → CUDA codegen → nvcc → GPU execution.
- 9 Transformer fusion patterns (GEMM+Bias+GeLU, LayerNorm fusion, etc.).
- 10.5 TFLOPS peak on RTX 2070 (37% of SM75 theoretical peak).
- Templated CUDA generation via Jinja2 with type/shape specialization.
LLM Scaling & Distributed Systems
- Multi-process runtime implementing Megatron-style Tensor Parallelism and Pipeline Parallelism.
- GPipe Scheduler: Fill-drain micro-batching to minimize idle bubbles.
- KV Cache Sharding: Distributed attention state to scale beyond single-GPU VRAM limits.
- Bit-identical validation on Qwen2-0.5B weights.
Production Serving Runtime
- OpenAI-compatible inference server (/v1/completions, /v1/chat/completions).
- Continuous batching, SSE streaming, KV cache management.
- Prometheus metrics, graceful shutdown, health checks.
- 33/33 unit tests + 6/6 end-to-end scenarios passing.
LLM-as-a-Service Platform (Production-Ready)
- High-concurrency backend with OpenAI-compatible API.
- ACID Billing: PostgreSQL-backed financial ledger with Decimal precision.
- Distributed Rate Limiting: Redis ZSET sliding window (multi-worker safe).
- Tool calling execution layer, Stripe integration, admin dashboard.
- Production stack: Docker Compose, Gunicorn, Prometheus.
Mathematical Model Compression
- From-scratch implementation of AWQ and GPTQ algorithms.
- Validated intelligence preservation on Qwen2-0.5B with 26.05 Perplexity at 4-bit.
- Deep-dive study on Hessian-based error compensation vs activation salience.
- flash-attention-sm75-register-fused: Register-fused FlashAttention for Turing (5.0 TFLOPS peak, roofline-validated).
- flash-attention-sm75: FlashAttention v1 forward pass in CUDA for SM75.
- fused-backward-kernels-sm75: Fused GEMM+Bias+GeLU backward kernels (3.1× faster than autograd at M=1024).
- rag-inference-stack: High-speed local RAG using ChromaDB and sentence-transformers.
- speculative-decoding-runtime: Accelerated inference (1.41× speedup) via draft-model verification.
- vlm-inference-runtime: Multi-modal deployment wrapper for Vision-Language Models.
- lora-inference-runtime: Multi-tenant serving with sub-3ms adapter hot-swapping.
| Layer | Technologies |
|---|---|
| Silicon & Hardware | CUDA C++, PTX Assembly, Tensor Cores (WMMA), CUDA Graphs, Nsight Compute |
| Compilers & Codegen | IR design, CUDA codegen (Jinja2), MLIR/LLVM (studied), TVM concepts |
| AI Frameworks | PyTorch, HuggingFace Transformers, PEFT, Tokenizers, ONNX |
| Distributed & Infra | NCCL/Gloo, torch.distributed, Tensor Parallelism, Pipeline Parallelism |
| Serving & Runtime | FastAPI, Continuous Batching, KV Cache Management, SSE Streaming |
| Backend & Scaling | Redis (ZSET Rate Limiting), PostgreSQL (ACID), ChromaDB, Prometheus |
| DevOps | Docker Compose, Gunicorn, Nginx, GitHub Actions |
| Languages | C, C++ (17/20), CUDA, PTX, Python, Rust, TypeScript (basic) |
| Achievement | Project |
|---|---|
| 32.4k tok/s peak throughput | mini-llm-inference-engine |
| 87% INT8 Tensor Core ceiling | mini-llm-inference-engine |
| 10.5 TFLOPS compiler-generated | llm-fusion-compiler |
| Beats cuBLAS at 2048² GEMM | sm75-tensorcore-microkernel |
| 1.000 Cosine Similarity INT4 vs FP16 | fused-int4-gemm-sm75 |
| Bit-identical distributed TP | distributed-inference-engine |
| 1.41× speedup speculative decoding | speculative-decoding-runtime |
| 26.05 PPL 4-bit AWQ | quantization-runtime |
| R² = 0.9996 comm cost model | comm-cost-modeling |
AI Infrastructure Engineer (Contract) — Confidential Leading Chinese LLM Company (Under NDA) | Sep 2025 – Mar 2026
Built Rust-based ingestion pipelines with Tokio async and backpressure-safe systems supporting an in-production LLM stack.
Software Architecture Lead & Operations Manager — ZBrasil (Cross-border E-commerce) | Apr 2025 – Aug 2025
Led backend architecture and GPU infrastructure decisions.
- Contributed to LLM Inference Handbook (llm-inference-at-scale) — module on observability signal coverage for LLM serving.
- LinkedIn: linkedin.com/in/joaofelipescheuer
- Email: johnfelipe13@gmail.com
- WhatsApp: +55 41 99705-4864
- WeChat: JohnScheuer7
- Location: Curitiba, Brazil (GMT-3) — Open to Relocation Worldwide
Code the math, scale the intelligence.