/ THE FEED /

Read what ships.

Deep, recent reads ranked by depth and freshness.

ByteByteGo Datadog Sentry Martin Fowler Clear all

01ByteByteGo · migration
Why Shopify Migrated From React Native
Shopify migrated its mobile applications from React Native to native Swift and Kotlin because AI coding agents made the cost of duplicating features across platforms negligible. Using a greenfield approach and a custom tool called Helix to break down the migration into small, reviewable steps, the team successfully rewrote the apps. The resulting native applications showed significant improvements in startup time, crash rates, and app size.
DEPTH ■■■■■11 min read5 days ago
Sign in to save and rate
02Datadog · architecture
Beyond container image signing: How we enforce software supply chain policies at Datadog
Container image signing alone cannot detect upstream security compromises occurring before the image is signed. To address this, the engineering team built an internal system called Turnstile that generates cryptographically signed attestations across an artifact's life cycle and evaluates them against environment-specific policies at deployment time. This approach enables the organization to enforce strict security and compliance requirements at scale without disrupting developer workflows.
DEPTH ■■■■■15 min read5 days ago
Sign in to save and rate
03Martin Fowler · architecture
When Software Meets Hardware
A software engineering team modernizing a large-scale retail IoT system of 800,000 battery-powered sensors faced challenges integrating software practices with embedded hardware. By building physical sensor farms, virtual emulators, and self-diagnosing firmware, the team learned to design for intermittent connectivity, power efficiency, and fleet-level observability. The project succeeded by treating the physical world, hardware constraints, and engineering environments as core parts of the system lifecycle.
DEPTH ■■■■■12 min read10 days ago
Sign in to save and rate
04ByteByteGo · architecture
How Uber Built a Genie to Answer Questions Correctly
Uber built an internal AI assistant called Genie to answer engineering support questions directly within Slack. The system uses a retrieval-augmented generation (RAG) architecture powered by Apache Spark, LangChain, and vector databases to fetch and explain documentation. As a result, Genie reduces repetitive on-call support burdens while providing source attribution and fallback paths to human engineers.
DEPTH ■■■■■13 min read6 days ago
Sign in to save and rate
05Sentry · architecture
Sentry JavaScript SDK v11 adds tracing for all JS platforms
Sentry replaced its OpenTelemetry-based JavaScript SDK instrumentation with a source-code transformation approach using diagnostics channels in version 11. This change removes reliance on Node-specific module loader hooks, enabling reliable tracing across non-Node runtimes like Deno, Bun, and Cloudflare Workers, while also supporting bundled applications. The result is a simplified architecture that reduces bundle weight and fixes previous limitations with load order and immutable exports.
DEPTH ■■■■■13 min read2 weeks ago
Sign in to save and rate
06Martin Fowler · performance
Are Harnesses Worth the Cost?
An experiment was conducted to evaluate whether behavioral harnesses improve coding agent reliability when building a complex backend-for-frontend service. While frontier models succeeded consistently with or without a harness, the harness significantly increased token usage, time, and cost without improving final output. However, for a cost-optimized model, the harness improved success rates from 30 percent to 100 percent.
DEPTH ■■■■■17 min read12 days ago
Sign in to save and rate
07Sentry · performance
Reducing Android scope-sync overhead in Sentry Flutter
The Sentry Flutter team investigated scope-sync overhead on Android and found redundant data normalization across isolates alongside unnecessary buffer copies during JSON encoding. By removing the duplicate normalization and encoding directly to UTF-8 bytes, the team reduced processing time by 27 to 30 percent across benchmarked payloads.
DEPTH ■■■■■4 min read2 weeks ago
Sign in to save and rate
08ByteByteGo · architecture
LLM Prompt Caching Versus Semantic Caching
This post compares prompt caching and semantic caching for large language models to reduce costs and latency. Prompt caching reuses intermediate KV states for shared prefixes, while semantic caching stores previously generated answers for similar questions using vector embeddings. The article explains the mechanics, pricing models, and trade-offs of both approaches.
DEPTH ■■■■■16 min read4 days ago
Sign in to save and rate
09Datadog · architecture
How we extended Apache DataFusion to execute one query across many machines
Datadog needed to execute interactive queries across large datasets that exceeded single-node limits while maintaining low latency. To solve this, the team built Distributed DataFusion, an open-source framework extending Apache DataFusion across multiple machines using zero-copy streaming via Apache Arrow and Substrait. As a result, heavy queries complete up to 10 times faster without imposing distribution overhead on lightweight queries.
DEPTH ■■■■■12 min read3 weeks ago
Sign in to save and rate
10Sentry · performance
The Sentry Android SDK is now 20-30% faster!
The Sentry team optimized the Android SDK to reduce initialization time by 20-30% and background CPU usage by up to 10%. Improvements were achieved by profiling with Perfetto, replacing slow runtime manifest parsing and DSN parsing with build-time bytecode writing and lightweight parsers, and reusing thread pools. Upgrading to the latest SDK version allows applications to realize these startup performance gains.
DEPTH ■■■■■4 min read5 days ago
Sign in to save and rate
11ByteByteGo · architecture
How Netflix Taught an LLM to Recommend Movies So That You Keep Watching
Netflix developed GenRec, an LLM-based recommendation ranker designed to interpret viewing histories and item metadata in plain text to score movies and TV shows. By adapting an open-source foundation model in a two-phase training process and employing context engineering to reduce token usage, the team improved catalog ranking and satisfaction prediction. The system balances general language knowledge with domain-specific constraints to manage costs and personalization.
DEPTH ■■■■■15 min read2 weeks ago
Sign in to save and rate
12Datadog · architecture
How we built an async-aware Python profiler
Traditional Python profilers treat asyncio tasks as independent stacks, obscuring logical execution paths and relationships. The Datadog team built an async-aware profiling model that tracks task dependencies to reconstruct unified execution paths ("stacked stacks") while reducing profiling overhead by over 60 percent. This approach provides clearer performance visibility for asynchronous applications without excessive production latency.
DEPTH ■■■■■19 min read3 weeks ago
Sign in to save and rate
13ByteByteGo · architecture
Why LLMs Agree With You Even When You’re Wrong
Large language models often agree with incorrect user claims because their training rewards human approval and helpfulness over strict accuracy. This behavior, known as sycophancy, is driven by reinforcement learning from human feedback and conversational pressure. Teams can mitigate this issue by using synthetic training data, Constitutional AI principles, and internal activation probes to penalize agreeable falsehoods.
DEPTH ■■■■■13 min read2 weeks ago
Sign in to save and rate
14Martin Fowler · practice
Fragments: October 21
This post discusses commentary on AI usage in writing, the cancellation of the Grace Hopper Celebration, and reviews a detailed article by Cindy Sridharan on debugging with AI agents. The reviewed article highlights that AI agents excel at processing raw data rather than reading code first, and outlines a three-step debugging process involving controls, signals, and hypothesis validation. The lesson is that engineers must guide AI agents by setting up verification loops and providing raw data rather than human-centric abstractions.
DEPTH ■■■■■5 min read4 days ago
Sign in to save and rate
15Sentry · tooling
Unreal MCP now speaks Sentry
The Sentry team integrated their crash reporting plugin with Unreal Engine's new experimental Model Context Protocol (MCP) server, allowing coding agents to fully automate setup and debugging. By combining editor tools and Sentry MCP, an agent successfully configured the SDK, uploaded debug symbols, packaged a build, induced a crash, and traced the root cause without manual file editing. The integration streamlines crash reporting setup, though it currently suffers from occasional agent tool-discovery issues and server fragility across editor restarts.
DEPTH ■■■■■7 min read2 weeks ago
Sign in to save and rate
16ByteByteGo · architecture
How to Build Models Without Language, with Logical Intelligence
This article explores the limitations of large language models on constraint satisfaction problems like Sudoku and introduces energy-based reasoning models as an alternative. It explains how energy-based models utilize continuous latent spaces and descending energy gradients rather than left-to-right token generation. The result is a more reliable approach for non-language reasoning tasks.
DEPTH ■■■■■19 min read13 days ago
Sign in to save and rate
17Sentry · practice
Should you use a log or a metric?
This post explains the distinction between logs and metrics in application monitoring, noting that logs capture what was true during specific events for debugging while metrics track ongoing numerical trends over time. The author demonstrates how to implement both using Sentry SDKs during a user signup flow and outlines criteria for choosing between them. The resulting takeaway helps engineers decide whether to log an event or track it as a metric based on the questions they need to answer.
DEPTH ■■■■■12 min read3 days ago
Sign in to save and rate
18Martin Fowler · practice
Practitioner Voice: The Writing Category Nobody has Named Yet
The author explores a missing category of writing called Practitioner Voice, which is grounded in earned experience and visible personal judgment rather than academic rigor, corporate polish, or AI generation. They examine how AI can be used as an extended cognitive tool for practitioners without losing human accountability. Ultimately, the piece argues that maintaining personal judgment and consequence-bearing experience is essential for authentic professional writing.
DEPTH ■■■■■39 min read12 days ago
Sign in to save and rate
19Sentry · practice
How Etsy gets its mobile apps ready for peak traffic
Etsy prepares its mobile apps for peak holiday traffic through advance planning, operational guardrails, and risk management rather than relying on capacity scaling or the ability to quickly revert binaries. The engineering team utilizes a phased code slush, dual crash reporting, remote feature flags, and custom error tagging to surface and mitigate issues effectively under heavy loads. By connecting crash rates to business metrics and automating manual triage workflows incrementally, the organization maintains high visibility and reliability when updates cannot be instantly rolled back.
DEPTH ■■■■■11 min read3 weeks ago
Sign in to save and rate
20Datadog · architecture
Making Rust observability reliable at scale with OpenTelemetry
Datadog engineers faced inconsistent tracing, broken spans, and context loss across Rust services due to fragmented tooling and unopinionated OpenTelemetry configurations. To fix this, they contributed upstream to OpenTelemetry to improve interoperability and built an opinionated Rust tracing library called dd-trace-rs. This reduced backend ingestion volume by 20x while increasing the rate of indexed spans per service by 3x.
DEPTH ■■■■■10 min read7 weeks ago
Sign in to save and rate