Stacks
What tools and technologies companies actually use internally.
Sourced from engineering blogs, case studies, public repos, and customer testimonial pages. Only verified information is included.
Azure is exclusive cloud provider. Uses Notion as central knowledge hub.
GCP TPUs and AWS Trainium for training. GKE for eval infra. Notably private about internal tooling.
VS Code fork. Uses NVIDIA A100 GPUs for inference. gRPC instead of VS Code's JSON serialization.
Dogfoods own platform for deployments. Turborepo migrated from Go to Rust.
Fully dogfoods own product. Same GraphQL API used internally and publicly.
C++ and Rust for the rendering engine compiled to WebAssembly. TypeScript for the web app.
Dogfoods Notion for docs and project management. Sharded Postgres from monolith to 480 logical shards.
Dogfoods everything. 2M-line Rails monolith, 1,200+ MySQL hosts, 5.5M queries/sec. Actions runs 4,500 concurrent 32-core runners.
Builds in public from a monorepo. Realtime server in Elixir/Phoenix. Auth forked from GoTrue.
Possibly the world's largest Ruby codebase (20M+ lines with Sorbet). Bazel builds 50M lines in ~15 minutes. 5,978 deploys in 2022.
Go for blockchain infra (Rosetta/Mesh). Early Coinbase built on Ruby on Rails.
Core backend on Elixir/BEAM VM. Switched Read States from Go to Rust. ScyllaDB replaced Cassandra for trillions of messages.
Built and open-sourced Backstage for developer portals.
Built and open-sourced Spinnaker for continuous delivery.
Historical Python backend evolving to Go services. Uses Apache Thrift for RPC.
Created Apache Airflow and Apache Superset. JS Style Guide has 148k GitHub stars.
Monorepo with Bazel. Built M3, Jaeger, and H3. 100K+ deployments/week via custom 'Up' platform.
Uses Slack for internal comms. Hack (PHP derivative) backend. Vitess handles 2.3M queries/sec at peak. 310M traces/day.
Created Zipkin (distributed tracing) and Snowflake (ID generation). Scala-heavy codebase. Finagle RPC framework.
Mostly custom internal tools. Open-sourced Bazel, Kubernetes, and Go. Runs on Borg cluster manager.
Heavily custom internal tooling. Acquired FoundationDB in 2015. One of the largest Cassandra users.
Owns GitHub. Dogfoods Azure and Microsoft 365 suite.
Heavily custom infra. Actively migrating from C to Rust on mobile. Open-sourced React, RocksDB, and PyTorch.
One of the largest Ruby on Rails codebases (2.8M+ lines). Uses Vitess for MySQL sharding.
Runs own global network. Dogfoods Workers, D1, and R2.
Dogfoods own product for monitoring. Uses eBPF for kernel-level observability. Temporal for workflow orchestration.