/ THE FEED /
Deep, recent reads ranked by depth and freshness.
01PlanetScale · architecture
Designing a sharded Postgres architecture requires grouping tables around shared query keys rather than starting from table structures alone. The post details how to configure shard groups, reference tables, SQL expressions in shard indexes, and global secondary indexes using Neki. This setup enables efficient single-shard queries and transactions while maintaining full Postgres semantics.
DEPTH ■■■■■8 min read2 days ago
02Shopify · architecture
Engineering teams outgrew their local machines while running parallel AI mobile development agents, constrained by heavy builds and lack of iOS tools on Linux. To solve this, they built Remote Dev using warm pools of remote Macs connected via SSH alongside separate Linux VMs for Android virtualization, paired with agent skills and live browser streaming. This setup shifted workflow bottlenecks, increasing AI-merged pull requests from 6 percent to 61 percent.
DEPTH ■■■■■9 min read3 days ago
03Shopify · architecture
Shopify uses a continual learning flywheel to post-train open models, such as NVIDIA Nemotron, to serve as dedicated subagents for specific tasks like GraphQL generation. By optimizing inference and utilizing automated self-healing to generate training data from production failures, the team successfully created task experts that outperform frontier models while reducing serving costs by 90-98% and improving response times.
DEPTH ■■■■■5 min read4 days ago
04PlanetScale · practice
Postgres ON DELETE CASCADE can cause production outages, replication failures, and performance degradation during large deletions or schema migrations due to long-running transactions holding locks and generating massive WAL. The author recommends using soft deletes with batched background cleanup instead to keep transactions short and bounded. This approach avoids table locks and simplifies data recovery.
DEPTH ■■■■■5 min read4 days ago
05Sentry · architecture
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
06Shopify · architecture
Shopify needed to group identical product listings from millions of different merchants under a single global identifier. To solve this at scale without comparing every possible pair, the team implemented a multi-stage pipeline using vector retrieval, a tiered scoring system of ML models, and a bounded graph clustering approach. This architecture successfully standardizes product data across the entire platform while controlling computational costs.
DEPTH ■■■■■13 min read5 days ago
07Sentry · performance
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
08Shopify · tooling
The team built an automated scanner called Overexposed to track internet-facing services and verify access controls across Kubernetes and Cloud Run. By querying live cloud inventories and probing endpoints like an outsider, the scanner classifies exposure while avoiding false assumptions from static config files. As a result, the engineering organization improved accuracy and significantly reduced inconclusive findings over time.
DEPTH ■■■■■8 min read5 days ago
09PlanetScale · architecture
This post examines how PostgreSQL uses TOAST to manage oversized rows and variable-length columns through compression and off-row storage. It compares the pglz and LZ4 compression algorithms across different workloads, highlighting trade-offs in search windows, file sizes, and CPU overhead. The analysis demonstrates how these mechanisms impact storage efficiency and read performance for large text and JSON data.
DEPTH ■■■■■12 min read13 days ago
10Sentry · performance
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
11PlanetScale · performance
Following competitive benchmarks that highlighted opportunities for optimization, the developers of the TIN full-text search index for Postgres released versions 1.0.4 and 1.0.6. These updates added Snowball stemming for 18 languages, optimized top-k sorting queries with deterministic tiebreakers, and improved overall query performance. As a result, benchmark tests show that TIN outperforms competing extensions across conjunction, disjunction, and phrase query workloads.
DEPTH ■■■■■8 min read2 weeks ago
12Shopify · architecture
Training and evaluating shopping agents is difficult due to changing live store environments, bot detection, and limited hand-built test stores. The team developed ShopGym, a framework that converts live storefronts into self-contained, anonymized sandbox shops and generates benchmark tasks. Evaluation showed that synthetic shops preserve key structural properties and behavioral alignment with live stores, giving agents a reliable environment to practice and improve.
DEPTH ■■■■■6 min read3 weeks ago
13PlanetScale · architecture
To reduce overhead when routing queries across PostgreSQL shards, the Neki router avoids unnecessary parsing and decodes responses lazily. By keeping data in its original wire format and only decoding columns when strictly required for operations like limits or sorting, the router significantly improves performance.
DEPTH ■■■■■16 min read3 weeks ago
14Sentry · tooling
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
15PlanetScale · architecture
Neki implements PostgreSQL sequences in a sharded system by handling volatile and stable expressions at the router level rather than pushing them to shards. Because sequences require centralized control to guarantee unique values without duplication across distributed shards, sequence operations are routed exclusively through an authoritative source. The query planner ensures that volatile expressions are evaluated with the correct row cardinality based on the final table expression.
DEPTH ■■■■■14 min read11 days ago
16Sentry · practice
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
17PlanetScale · architecture
PlanetScale expanded its database offering to Microsoft Azure by adapting its Kubernetes-based infrastructure to handle Azure's networking constraints. The engineering team overcame Azure's private IP limits and slow pod startup times by implementing block-based IP allocation via a custom CNI plugin. This approach successfully increased IP capacity and removed the Kubernetes API server from the critical path during pod initialization.
DEPTH ■■■■■3 min read12 days ago
18Shopify · tooling
Shopify is migrating its mobile apps from React Native to native Swift and Kotlin using an internal LLM-powered tool called Helix. Helix breaks migrations down into small checkpoints and enforces strict quality gates covering behavior, UI equivalence, architectural compliance, and human review. This iterative loop allows the team to reliably generate and migrate hundreds of screens to native code.
DEPTH ■■■■■8 min read4 weeks ago
19Sentry · practice
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
20Shopify · migration
Shop migrated its mobile app from React Native to native Swift and Kotlin by leveraging AI coding agents to accelerate the rewrite. The migration resulted in improved startup times, higher session stability, smaller Android app sizes, and smoother rendering performance.
DEPTH ■■■■■5 min read6 weeks ago
