| Vector Growth and Iterator Invalidation | C++ & Systems | easy |
| Deleting a Derived Object Through a Base Pointer | C++ & Systems | easy |
| Reordering Members to Shrink a Struct | C++ & Systems | easy |
| Returning a Named Local, NRVO and the Implicit Move | C++ & Systems | medium |
| False Sharing in a Parallel Counter | C++ & Systems | medium |
| Virtual Dispatch During Construction | C++ & Systems | medium |
| Relaxed Atomics and the Message-Passing Pattern | C++ & Systems | hard |
| Pointer Chasing vs a Contiguous Scan | C++ & Systems | easy |
| Diamond Inheritance and Virtual Base Subobjects | C++ & Systems | hard |
| fork() and Copy-on-Write Pages | C++ & Systems | medium |
| Reference Collapsing Through a Forwarding Reference | C++ & Systems | medium |
| Trivially Copyable Types and the memcpy Fast Path | C++ & Systems | medium |
| TLB Hit Rate and Effective Memory Access Time | C++ & Systems | medium |
| Comparing -1 to an unsigned int | C++ & Systems | easy |
| LRU Cache with O(1) Get and Put | C++ & Systems | medium |
| Parsing Length-Prefixed Frames from a Byte Stream | C++ & Systems | medium |
| A Lock-Free Stack Under Preemption | C++ & Systems | hard |
| Splitting a Virtual Address: Page Number and Offset | C++ & Systems | easy |
| Explicit Specialization vs Overload Resolution | C++ & Systems | medium |
| CTAD and the Braced-Initialization Trap | C++ & Systems | medium |
| Consolidated Best Bid and Offer Across Venues | C++ & Systems | hard |
| Why epoll Scales Where select Does Not | C++ & Systems | easy |
| Fixed-Block Pool Allocator with a Free List | C++ & Systems | medium |
| Why Sorting the Data Makes the Loop Faster | C++ & Systems | easy |
| The Price of an Interface: sizeof Edition | C++ & Systems | hard |
| Fixed-Capacity Ring Buffer with Wraparound | C++ & Systems | medium |
| What Can This Two-Thread Program Print? | C++ & Systems | hard |
| Arena Allocator: Bump, Align, Reset | C++ & Systems | medium |
| Recovering Two Lost Segments: SACK vs Cumulative ACK | C++ & Systems | medium |
| Why Small Order Messages Stall for 40 Milliseconds | C++ & Systems | medium |
| A Stalled Order Thread on a Pinned Core | C++ & Systems | medium |
| Two Constrained Overloads, One Signature | C++ & Systems | hard |
| Price-Time Priority Limit Order Book | C++ & Systems | hard |
| What Does Kernel Bypass Actually Skip? | C++ & Systems | easy |
| AoS vs SoA: Cache Lines on a Single-Field Scan | C++ & Systems | easy |
| Two enable_if Overloads, One Call | C++ & Systems | medium |
| Which Returned Reference Dangles? | C++ & Systems | easy |
| UDP Multicast Market Data: Gaps and A/B Arbitration | C++ & Systems | hard |
| Mutex or Spinlock on the Hot Path? | C++ & Systems | medium |
| Covariant Return Types in a clone() Hierarchy | C++ & Systems | easy |
| Parsing Wire Bytes: Network Byte Order on a Little-Endian Host | C++ & Systems | easy |
| Fold Expressions over an Empty Parameter Pack | C++ & Systems | medium |
| One std::move, Four Outcomes | C++ & Systems | medium |
| The Power-of-Two Stride That Thrashes L1 | C++ & Systems | hard |
| Open Congestion Window, Stalled Sender | C++ & Systems | medium |
| One Read per Wakeup under EPOLLET | C++ & Systems | medium |
| Empty Base Optimization and Object Size | C++ & Systems | medium |
| What Does x + 1 > x Return? | C++ & Systems | medium |
| Function-Local Statics and Thread-Safe Initialization | C++ & Systems | easy |
| TCP Congestion Window After a Packet Loss | C++ & Systems | medium |
| In-Order Delivery from an Out-of-Order Feed | C++ & Systems | medium |
| Does the fetch_add Break the Release Sequence? | C++ & Systems | hard |
| Minor or Major: Classifying the Page Fault | C++ & Systems | easy |
| Where Do Short Strings Live? | C++ & Systems | easy |
| One-Shot Leader Election with CAS | C++ & Systems | medium |
| Why free() Does Not Shrink RSS | C++ & Systems | hard |
| One Inline Function, Two Different Bodies | C++ & Systems | hard |
| One Overload Hides the Whole Base Set | C++ & Systems | medium |
| Building a Heap with make_heap vs Repeated push_heap | C++ & Systems | medium |
| Hot-Swapping a Config Behind a shared_ptr | C++ & Systems | medium |
| Which swap Does Generic Code Actually Call? | C++ & Systems | hard |
| TLB Reach with 4 KiB vs 2 MiB Pages | C++ & Systems | medium |
| push_back of the Vector's Own Element | C++ & Systems | hard |
| A Misaligned Atomic Increment and the Split Lock | C++ & Systems | hard |
| Rehashing and Reference Stability in std::unordered_map | C++ & Systems | medium |
| The Undefined Reference That Compiled Cleanly | C++ & Systems | medium |
| Name Mangling and extern "C" Linkage | C++ & Systems | easy |
| Why a Winning CAS Still Cannot Free the Node | C++ & Systems | hard |
| std::map operator[] on a Missing Key | C++ & Systems | easy |
| The Greedy Forwarding Constructor | C++ & Systems | hard |
| Graceful Shutdown Inside a SIGINT Handler | C++ & Systems | hard |
| Default Arguments Meet Virtual Dispatch | C++ & Systems | medium |
| Which Pointer Sees the New Object After Placement New? | C++ & Systems | hard |
| Startup Registration Across Translation Units | C++ & Systems | medium |
| Strict Aliasing and the Reinterpreted Wire Buffer | C++ & Systems | hard |
| const vs constexpr vs constinit and Who Guarantees Constant Initialization | C++ & Systems | medium |
| make_shared, weak_ptr, and a 64 MiB Snapshot | C++ & Systems | medium |
| Vector Reallocation and the Missing noexcept | C++ & Systems | hard |
| NUMA First Touch on the Wrong Socket | C++ & Systems | hard |
| Can This Call Still Leak in C++17? | C++ & Systems | hard |
| What Does std::remove Actually Remove? | C++ & Systems | easy |
| Seqlock Ordering for a Market Data Snapshot | C++ & Systems | hard |
| Three Moves, One Guarantee | C++ & Systems | medium |
| A Denormal Latency Cliff in an EWMA Loop | C++ & Systems | medium |
| Two-Phase Lookup and the Dependent Base | C++ & Systems | hard |
| The Store That Invalidates Every Reader | C++ & Systems | hard |
| Double-Checked Locking with a Plain Pointer | C++ & Systems | hard |
| Floating-Point Non-Associativity and the Vectorized Reduction | C++ & Systems | hard |
| Timing with rdtsc: Serialized Reads and Invariant Ticks | C++ & Systems | medium |
| One Acquire Fence, Four Relaxed Polls | C++ & Systems | hard |
| The Price of the Strong Guarantee | C++ & Systems | medium |
| Object Slicing in a Container of Base Objects | C++ & Systems | easy |
| The Destructor That Throws Twice | C++ & Systems | hard |
| auto Meets the vector<bool> Proxy | C++ & Systems | medium |
| Dangling string_view: Temporary Strings and substr | C++ & Systems | medium |
| Can This Consumer Sleep Forever? | C++ & Systems | medium |
| LD_PRELOAD, the PLT, and a Library That Calls Itself | C++ & Systems | hard |
| dynamic_cast Failure Modes and a static_cast Trap | C++ & Systems | medium |
| Pointer Adjustment Across Multiple Base Subobjects | C++ & Systems | hard |
| Is This std::async Call Fire-and-Forget? | C++ & Systems | medium |
| A Constructor Throws Halfway. Who Cleans Up? | C++ & Systems | hard |
| Sorting With a <= Comparator | C++ & Systems | hard |
| Where Do 8 Megabytes of Zeros Go? | C++ & Systems | easy |
| clock_gettime in 18 Nanoseconds: Where Did the Syscall Go? | C++ & Systems | medium |
| What Does memory_order_consume Actually Order? | C++ & Systems | hard |